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Search for "arenes" in Full Text gives 309 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
Visible-light-driven NHC and organophotoredox dual catalysis for the synthesis of carbonyl compounds
- Vasudevan Dhayalan
Beilstein J. Org. Chem. 2025, 21, 2584–2603, doi:10.3762/bjoc.21.200
- used for late-stage modification of bioactive compounds, including natural products. These developments will find suitable applications in medicinal chemistry for introducible organosilyl groups (Scheme 5) [55]. A visible-light-induced Friedel–Crafts acylation of arenes and heteroarenes was reported by
- Studer et al., which belongs to the class of aryl and heteroaryl electrophilic substitutions and is a highly versatile synthetic transformation in traditional organic chemistry. A highly regioselective dual catalytic approach for the novel acylation of electron-rich benzo-fused arenes or heterocycles 15
- enables the highly regioselective formation of meta-acylated ketone products 16 through a radical pathway. The NHC-catalyzed novel acylation was achieved using acyl fluorides 4 and electron-rich arenes 15 in the presence of NHC (20 mol %), photocatalyst (5 mol %), and Cs2CO3 in CH3CN at room temperature
Graphical Abstract
Scheme 1: NHC-catalyzed umpolung strategy for the metal-free synthesis of amide via dual catalysis.
Scheme 2: Visible-light promoted cooperative NHC/photoredox catalyzed ring-opening of aryl cyclopropanes.
Scheme 3: NHC-catalyzed benzylic C–H acylation by dual catalysis.
Scheme 4: NHC/photoredox-catalyzed three-component coupling reaction for the preparation of γ-aryloxy ketones....
Scheme 5: NHC-catalyzed silyl radical generation from silylboronate via dual catalysis.
Scheme 6: NHC-catalyzed C–H acylation of arenes and heteroarenes through photocatalysis.
Scheme 7: NHC-catalyzed iminoacylation of alkenes via photoredox dual organocatalysis.
Scheme 8: NHC/photoredox catalyzed direct synthesis of β-arylketoesters.
Scheme 9: Visible-light-driven NHC/photoredox catalyzed borylacylation of alkenes.
Scheme 10: NHC-catalyzed oxidative functionalization of cinnamaldehyde.
Scheme 11: NHC/photocatalyzed oxidative Smiles rearrangement.
Scheme 12: NHC-catalyzed synthesis of cyclohexanones through photocatalyzed annulation.
Scheme 13: Dual organocatalyzed meta-selective acylation of electron-rich arenes and heteroarenes using blue L...
Scheme 14: Asymmetric synthesis of fused pyrrolidinones via organophotoredox/N‑heterocyclic carbene dual catal...
Synthesis and characterization of a isothiouronium-calix[4]arene derivative: self-assembly and anticancer activity
- Giuseppe Granata,
- Loredana Ferreri,
- Claudia Giovanna Leotta,
- Giovanni Mario Pitari and
- Grazia Maria Letizia Consoli
Beilstein J. Org. Chem. 2025, 21, 2535–2541, doi:10.3762/bjoc.21.195
- , Via Paolo Gaifami 9, 95126 Catania, Italy 10.3762/bjoc.21.195 Abstract Calix[n]arenes are polyphenolic macrocycles known for their remarkable synthetic versatility, which supports their broad application in various areas, including drug discovery. Their unique conformational features, functionality
- [7], cyclic peptides [8], cucurbiturils [9], resorcinarenes [10], pillarenes [11], prismarenes [12], and calix[n]arenes have proven to be particularly valuable. Calix[n]arenes, a family of polyphenolic macrocyclic oligomers, are widely utilized in applications ranging from materials science to life
Graphical Abstract
Scheme 1: Procedure for the synthesis of compound 3.
Figure 1: 1H NMR (left) and 13C NMR (right) spectra of compound 3 in DMSO-d6 (400.13 MHz, 297 K).
Figure 2: Intensity-weighted mean hydrodynamic diameter (left), and zeta potential distribution (right) of co...
Figure 3: Antiproliferative effects by compound 3 and its chemical precursor 1. A) Results on proliferative k...
Pentacyclic aromatic heterocycles from Pd-catalyzed annulation of 1,5-diaryl-1,2,3-triazoles
- Kaylen D. Lathrum,
- Emily M. Hanneken,
- Katelyn R. Grzelak and
- James T. Fletcher
Beilstein J. Org. Chem. 2025, 21, 2524–2534, doi:10.3762/bjoc.21.194
- observed for these annulated molecules, while their analogous non-annulated control compounds were not bioactive. Keywords: annulation; arenes; antimicrobials; fused-ring systems; UV–vis spectroscopy; Introduction Polycyclic aromatic heterocycles are a diverse class of small molecules with utility in a
- subunits connected at the triazole C5 position were non-emissive under the conditions utilized, while the majority of the N1-connected analogs showed weak but observable signals. Such influence of triazole connectivity on the emission intensity of attached arenes has been previously reported [54]. Within
Graphical Abstract
Figure 1: Examples of polycyclic aromatic heterocycle structures: phenanthridine (left), 1,5-naphthyridine (c...
Figure 2: Overview of the synthetic scheme employed by this study.
Figure 3: Base-catalyzed [53] tandem deprotection/cycloaddition reaction conditions used to prepare 1,5-diaryl-1,...
Figure 4: Identity of 1,5-diaryl-1,2,3-triazole control compounds prepared from tandem deprotection/click con...
Figure 5: Exemplary comparison of 1H NMR aromatic signal shifts for annulated and non-annulated compounds (CD...
Figure 6: UV–visible absorbance spectra of annulated 13–18 (black lines) compared with their non-annulated co...
Palladium-catalyzed regioselective C1-selective nitration of carbazoles
- Vikash Kumar,
- Jyothis Dharaniyedath,
- Aiswarya T P,
- Sk Ariyan,
- Chitrothu Venkatesh and
- Parthasarathy Gandeepan
Beilstein J. Org. Chem. 2025, 21, 2479–2488, doi:10.3762/bjoc.21.190
- gram-scale synthesis under the optimized conditions. The reaction of 1a was performed on a 4.1 mmol (1.0 g) scale, yielding the C1–H-nitrated carbazole product 2a in 49% (0.585 g, 2.02 mmol) isolated yield (Scheme 4a). Given the importance of nitro-functionalized (hetero)arenes, we sought to access the
Graphical Abstract
Scheme 1: (a) Representative examples of bioactive nitrocarbazoles. (b) Traditional electrophilic aromatic su...
Figure 1: ORTEP diagram of compound 2a (CCDC 2478298).
Scheme 2: Effect of directing groups on the nitration of the carbazoles.
Scheme 3: Scope of the method. Reaction conditions: 1 (0.2 mmol, 1.0 equiv), Pd2(dba)3 (0.02 mmol, 10 mol %),...
Scheme 4: Gram-scale synthesis, directing group removal, and synthetic utility of our method.
Scheme 5: Key mechanistic studies.
Figure 2: Plausible catalytic cycle.
Catalytic enantioselective synthesis of selenium-containing atropisomers via C–Se bond formations
- Qi-Sen Gao,
- Zheng-Wei Wei and
- Zhi-Min Chen
Beilstein J. Org. Chem. 2025, 21, 2447–2455, doi:10.3762/bjoc.21.186
- synthetic approaches for constructing selenium-containing atropisomers have been reported, such as C–H selenylation of arenes, selenosulfonylation of vinylidene o-quinone methides (VQM), and hydroselenation of alkynes. Nevertheless, a comprehensive review that systematically summarizes these advances is
Graphical Abstract
Figure 1: Representative examples of chiral selenium-containing compounds.
Scheme 1: Rhodium-catalyzed atroposelective C–H selenylation reported by You’s group [18].
Scheme 2: Rhodium-catalyzed atroposelective C–H selenylation reported by Li et al. [19].
Scheme 3: Organocatalytic asymmetric selenosulfonylation of alkynes.
Scheme 4: Rhodium-catalyzed asymmetric hydroselenation of 1-alkynylindoles. *DCE/DCM 2:1 (v/v), −50 °C.
Scheme 5: Organocatalytic atroposelective hydroselenation of alkynes. *Using cat.3, 4 h.
Pd-catalyzed dehydrogenative arylation of arylhydrazines to access non-symmetric azobenzenes, including tetra-ortho derivatives
- Loris Geminiani,
- Kathrin Junge,
- Matthias Beller and
- Jean-François Soulé
Beilstein J. Org. Chem. 2025, 21, 2234–2242, doi:10.3762/bjoc.21.170
- hazardous diazonium salts and electron-rich arenes (mainly limited to phenols) [29][30][31], including metalated arenes [32][33]. The growing demand for structurally complex compounds across diverse applications has rendered the synthesis of non-symmetrical azoarenes with differently substituted azo bonds
Graphical Abstract
Figure 1: General overview of azobenzene chemistry. a) Selected examples and photoisomerization of azobenzene...
Scheme 1: Scope of aryl bromides in palladium-catalyzed dehydrogenative C–N coupling with phenylhydrazine (1a...
Scheme 2: Scope of arylhydrazines in palladium-catalyzed dehydrogenative C–N coupling with 2-bromotoluene (2a...
Scheme 3: Application to the synthesis of tetra-, tri or di-ortho-substituted azobenzenes via palladium-catal...
Figure 2: a) Proposed catalytic cycle for the one-pot palladium-catalyzed dehydrogenative C–N coupling for th...
Measuring the stereogenic remoteness in non-central chirality: a stereocontrol connectivity index for asymmetric reactions
- Ivan Keng Wee On,
- Yu Kun Choo,
- Sambhav Baid and
- Ye Zhu
Beilstein J. Org. Chem. 2025, 21, 1995–2006, doi:10.3762/bjoc.21.155
- , asymmetric synthesis of “inherently chiral” macrocycles have gained growing attention [22]. Practically, such reactions that yield “inherently chiral” macrocycles can be treated similarly as planar chirality (Scheme 6). The synthesis of calix[4]arenes via C–H arylation [23] is [31] (Scheme 6A), following the
- same procedure as in Scheme 5C. In analogy to Scheme 5B, the direct cyclization forging the planar chirality [24] in Scheme 6B is regarded as [31 10], in which two stereogenic arenes are proximate and the two distal arenes are considered diastereomeric. The desymmetrization cross-coupling of cavitands
Graphical Abstract
Scheme 1: Illustration of chirality and the intrinsic remoteness of stereogenic elements for axial chirality ...
Scheme 2: Illustrations of assignment using point chirality.
Scheme 3: Examples of reactions that establish axial chirality derived from biaryls.
Scheme 4: Examples of reactions that establish axial chirality derived from C=C bonds.
Scheme 5: Examples of reactions that establish planar chirality.
Scheme 6: Examples of reactions that establish “inherent” chirality.
Scheme 7: Parameterization of asymmetric reactions that establish axial chirality.
Figure 1: The relationship between the numbers of non-hydrogen atoms (N) in the chiral catalysts and the valu...
Synthesis of N-doped chiral macrocycles by regioselective palladium-catalyzed arylation
- Shuhai Qiu and
- Junzhi Liu
Beilstein J. Org. Chem. 2025, 21, 1917–1923, doi:10.3762/bjoc.21.149
- that inherently lacks symmetry [8][9]. One of the most typical representatives are calix[4]arenes (Figure 1a), first reported by Böhmer in 1994 [10], where asymmetric substitutions on the macrocyclic rim induce inherent chirality. Subsequent advancements have identified other inherent chiral systems
- non-classical chiral macrocycles, providing insights into molecular design of chiral macrocycles with high emissions. (a) Representatives of inherent chiral calix[4]arenes. (b) Molecular skeletons of inherent chiral N-doped macrocycles in this work. Crystal structures of compounds (a) 3a, (b) MC2, and
Graphical Abstract
Figure 1: (a) Representatives of inherent chiral calix[4]arenes. (b) Molecular skeletons of inherent chiral N...
Scheme 1: Synthesis of N-doped macrocycles MC1, MC2, and MC3. Reaction conditions: a) Pd2(dba)3, Pt-Bu3·HBF4,...
Figure 2: Crystal structures of compounds (a) 3a, (b) MC2, and (c) MC3. (d) Molecular arrangements of MC3. Hy...
Figure 3: (a) Absorptions and (b) emissions of compounds 3a, 3b, MC1, MC2, and MC3 measured in dichloromethan...
Figure 4: Calculated frontier molecular orbitals and relative energy levels of MC1 (left), MC2 (middle), and ...
Figure 5: (a) CD spectra, (b) |gabs|, and (c) glum values of enantiomers of MC1 measured in dichloromethane a...
Chiral phosphoric acid-catalyzed asymmetric synthesis of helically chiral, planarly chiral and inherently chiral molecules
- Wei Liu and
- Xiaoyu Yang
Beilstein J. Org. Chem. 2025, 21, 1864–1889, doi:10.3762/bjoc.21.145
- chirality originating from the rigid conformation of molecules lacking symmetry, which do not fit into the aforementioned four categories, are termed inherent chirality. Notable examples include inherently chiral calix[4]arenes and saddle-shaped medium-sized cyclic compounds. Catalytic asymmetric synthesis
- [49] and the Liu group [50] independently reported the asymmetric synthesis of inherently chiral calix[4]arenes through an enantioselective desymmetrization strategy. Starting from the achiral aniline-containing calix[4]arenes 52, we employed the CPA 11-catalyzed asymmetric Povarov reaction [51] with
- enamide 6a and various aldehydes 7 to break the symmetry of substrates 52, which was followed by a one-pot oxidative aromatization mediated by DDQ to yield the quinoline-containing inherently chiral calix[4]arenes 53 (Scheme 15). Notably, the prochiral calix[4]arenes bearing a disubstitution pattern on
Graphical Abstract
Figure 1: General structure of CPAs and selected CPAs with various chiral scaffolds.
Figure 2: Representative elements of molecular chirality.
Scheme 1: CPA-catalyzed asymmetric synthesis of azahelicenes via Fischer indole synthesis.
Scheme 2: CPA-catalyzed asymmetric synthesis of azahelicenes via sequential Povarov reaction and oxidative ar...
Scheme 3: CPA-catalyzed asymmetric synthesis of azahelicenes via sequential Povarov reaction involving 3-viny...
Scheme 4: CPA-catalyzed asymmetric synthesis of heterohelicenes via sequential Povarov reaction involving 2-v...
Scheme 5: Diverse enantioselective synthesis of hetero[7]helicenes via a CPA-catalyzed double annulation stra...
Scheme 6: CPA-catalyzed asymmetric synthesis of indolohelicenoids through enantioselective cycloaddition and ...
Scheme 7: Kinetic resolution of helical polycyclic phenols via CPA-catalyzed enantioselective aminative dearo...
Scheme 8: Kinetic resolution of azahelicenes via CPA-catalyzed transfer hydrogenation.
Scheme 9: Asymmetric synthesis of planarly chiral macrocycles via CPA-catalyzed electrophilic aromatic aminat...
Scheme 10: Enantioselective synthesis of planarly chiral macrocycles via CPA-catalyzed macrocyclization.
Scheme 11: (Dynamic) kinetic resolution of planarly chiral paracyclophanes via CPA-catalyzed asymmetric reduct...
Scheme 12: Kinetic resolution of macrocyclic paracyclophanes through CPA/Bi-catalyzed asymmetric allylation.
Scheme 13: Enantioselective synthesis of planarly chiral macrocycles via CPA-catalyzed coupling of carboxylic ...
Scheme 14: Kinetic resolution of substituted amido[2.2]paracyclophanes via CPA-catalyzed asymmetric electrophi...
Scheme 15: Enantioselective synthesis of inherently chiral calix[4]arenes via sequential CPA-catalyzed Povarov...
Scheme 16: Asymmetric synthesis of inherently chiral calix[4]arenes via CPA-catalyzed aminative desymmetrizati...
Scheme 17: Asymmetric synthesis of chiral heterocalix[4]arenes via CPA-catalyzed intramolecular SNAr reaction.
Scheme 18: Enantioselective synthesis of inherently chiral DDDs via CPA-catalyzed cyclocondensation.
Scheme 19: Asymmetric synthesis of saddle-shaped inherently chiral 9,10-dihydrotribenzoazocines via CPA-cataly...
Scheme 20: Enantioselective synthesis of inherently chiral saddle-shaped dibenzo[b,f][1,5]diazocines via CPA-c...
Scheme 21: Enantioselective synthesis of inherent chiral 7-membered tribenzocycloheptene oximes via CPA-cataly...
Photoswitches beyond azobenzene: a beginner’s guide
- Michela Marcon,
- Christoph Haag and
- Burkhard König
Beilstein J. Org. Chem. 2025, 21, 1808–1853, doi:10.3762/bjoc.21.143
- ) can interchange between tautomers to make a chalcogen bond with sulphur in the Z-isomer and a hydrogen bond in the E-isomer [64]. Extension of the conjugation with additional electron-rich arenes enables isomerisation with wavelengths up to >700 nm, with high PSS and high quantum yield. Electron-poor
Graphical Abstract
Figure 1: Energy diagram of a two-state photoswitch. Figure 1 was redrawn from [2].
Figure 2: Example of the absorption spectra of the isomers of a photoswitch with most efficient irradiation w...
Scheme 1: Photoswitch classes described in this review.
Figure 3: Azoheteroarenes.
Scheme 2: E–Z Isomerisation (top) and mechanisms of thermal Z–E isomerisation (bottom).
Scheme 3: Rotation mechanism favoured by the electron displacement in push–pull systems. Selected examples of...
Figure 4: A) T-shaped and twisted Z-isomers determine the thermal stability and the Z–E-PSS (selected example...
Figure 5: Effect of di-ortho-substitution on thermal half-life and PSS.
Figure 6: Selected thermal lifetimes of azoindoles in different solvents and concentrations. aConcentration o...
Figure 7: Aryliminopyrazoles: N-pyrazoles (top) and N-phenyl (bottom).
Scheme 4: Synthesis of symmetrical heteroarenes through oxidation (A), reduction (B), and the Bayer–Mills rea...
Scheme 5: Synthesis of diazonium salt (A); different strategies of azo-coupling: with a nucleophilic ring (B)...
Scheme 6: Synthesis of arylazothiazoles 25 (A) and heteroaryltriazoles 28 (B).
Scheme 7: Synthesis of heteroarylimines 31a,b [36-38].
Figure 8: Push–pull non-ionic azo dye developed by Velasco and co-workers [45].
Scheme 8: Azopyridine reported by Herges and co-workers [46].
Scheme 9: Photoinduced phase transitioning azobispyrazoles [47].
Figure 9: Diazocines.
Scheme 10: Isomers, conformers and enantiomers of diazocine.
Scheme 11: Partial overlap of the ππ* band with electron-donating substituents and effect on the PSS. Scheme 11 was ada...
Figure 10: Main properties of diazocines with different bridges. aMeasured in n-hexane [56]. bMeasured in THF. cMe...
Scheme 12: Synthesis of symmetric diazocines.
Scheme 13: Synthesis of asymmetric diazocines.
Scheme 14: Synthesis of O- and S-heterodiazocines.
Scheme 15: Synthesis of N-heterodiazocines.
Scheme 16: Puromycin diazocine photoswitch [60].
Figure 11: Indigoids.
Figure 12: The main representatives of the indigoid photoswitch class.
Scheme 17: Deactivation process that prevents Z-isomerisation of indigo.
Figure 13: Stable Z-indigo derivative synthesised by Wyman and Zenhäusern [67].
Figure 14: Selected examples of indigos with aliphatic and aromatic substituents [68]. Dashed box: proposed π–π in...
Scheme 18: Resonance structures of indigo and thioindigo involving the phenyl ring.
Scheme 19: Possible deactivation mechanism for 4,4'-dihydroxythioindigo [76].
Scheme 20: Effect of different heteroaryl rings on the stability and the photophysical properties of hemiindig...
Figure 15: Thermal half-lives of red-shifted hemithioindigos in toluene [79]. aMeasured in toluene-d8.
Scheme 21: Structures of pyrrole [81] and imidazole hemithioindigo [64].
Figure 16: Examples of fully substituted double bond hemithioindigo (left), oxidised hemithioindigos (centre),...
Scheme 22: Structure of iminothioindoxyl 72 (top) and acylated phenyliminoindolinone photoswitch 73 (bottom). ...
Scheme 23: (top) Transition states of iminothioindoxyl 72. The planar transition state is associated with a lo...
Scheme 24: Baeyer–Drewsen synthesis of indigo (top) and N-functionalisation strategies (bottom).
Scheme 25: Synthesis of hemiindigo.
Scheme 26: Synthesis of hemithioindigo and iminothioindoxyl.
Scheme 27: Synthesis of double-bond-substituted hemithioindigos.
Scheme 28: Synthesis of phenyliminoindolinone.
Scheme 29: Hemithioindigo molecular motor [85].
Figure 17: Arylhydrazones.
Scheme 30: Switching of arylhydrazones. Note: The definitions of stator and rotor are arbitrary.
Scheme 31: Photo- and acidochromism of pyridine-based phenylhydrazones.
Scheme 32: A) E–Z thermal inversion of a thermally stable push–pull hydrazone [109]. B) Rotation mechanism favoured...
Scheme 33: Effect of planarisation on the half-life.
Scheme 34: The longest thermally stable hydrazone switches reported so far (left). Modulation of thermal half-...
Figure 18: Dependency of t1/2 on concentration and hypothesised aggregation-induced isomerisation.
Figure 19: Structure–property relationship of acylhydrazones.
Scheme 35: Synthesis of arylhydrazones.
Scheme 36: Synthesis of acylhydrazones.
Scheme 37: Photoswitchable fluorophore by Aprahamian et al. [115].
Scheme 38: The four-state photoswitch synthesised by the Cigáň group [116].
Figure 20: Diarylethenes.
Scheme 39: Isomerisation and oxidation pathway of E-stilbene to phenanthrene.
Scheme 40: Strategies adapted to avoid E–Z isomerisation and oxidation.
Scheme 41: Molecular orbitals and mechanism of electrocyclisation for a 6π system.
Figure 21: Aromatic stabilisation energy correlated with the thermal stability of the diarylethenes [127,129].
Figure 22: Half-lives of diarylethenes with increasing electron-withdrawing groups [128,129].
Scheme 42: Photochemical degradation pathway promoted by electron-donating groups [130].
Figure 23: The diarylethenes studied by Hanazawa et al. [134]. Increased rigidity leads to bathochromic shift.
Scheme 43: The dithienylethene synthesised by Nakatani's group [135].
Scheme 44: Synthesis of perfluoroalkylated diarylethenes.
Scheme 45: Synthesis of 139 and 142 via McMurry coupling.
Scheme 46: Synthesis of symmetrical derivatives 145 via Suzuki–Miyaura coupling.
Scheme 47: Synthesis of acyclic 148, malonic anhydride 149, and maleimide derivatives 154.
Figure 24: Gramicidin S (top left) and two of the modified diarylethene derivatives: first generation (bottom ...
Scheme 48: Pyridoxal 5'-phosphate and its reaction with an amino acid (top). The analogous dithienylethene der...
Figure 25: Fulgides.
Scheme 49: The three isomers of fulgides.
Scheme 50: Thermal and photochemical side products of unsubstituted fulgide [150].
Figure 26: Maximum absorption λc of the closed isomer compared with the nature of the aromatic ring and the su...
Scheme 51: Possible rearrangement of the excited state of 5-dimethylaminoindolylfulgide [153].
Figure 27: Quantum yields of ring closure (ΦE→C) and E–Z isomerisation (ΦE→Z) correlated with the increasing s...
Scheme 52: Active (Eα) and inactive (Eβ) conformers (left) and the bicyclic sterically blocked fulgide 169 (ri...
Scheme 53: Quantum yield of ring-opening (ΦC→E) and E–Z isomerisation (ΦE→Z) for different substitution patter...
Scheme 54: Stobbe condensation pathway for the synthesis of fulgides 179, fulgimides 181 and fulgenates 178.
Scheme 55: Alternative synthesis of fulgides through Pd-catalysed carbonylation.
Scheme 56: Optimised synthesis of fulgimides [166].
Scheme 57: Photoswitchable FRET with a fulgimide photoswitch [167].
Scheme 58: Three-state fulgimide strategy by Slanina's group.
Figure 28: Spiropyrans.
Scheme 59: Photochemical (left) and thermal (right) ring-opening mechanisms for an exemplary spiropyran with a...
Figure 29: Eight possible isomers of the open merocyanine according to the E/Z configurations of the bonds hig...
Scheme 60: pH-Controlled photoisomerisation between the closed spiropyran 191-SP and the open E-merocyanine 19...
Scheme 61: Behaviour of spiropyran in water buffer according to Andréasson and co-workers [180]. 192-SP in an aqueo...
Scheme 62: (left box) Proposed mechanism of basic hydrolysis of MC [184]. (right box) Introduction of electron-dona...
Scheme 63: Photochemical interconversion of naphthopyran 194 (top) and spirooxazine 195 (bottom) photoswitches...
Scheme 64: Synthesis of spiropyrans and spirooxazines 198 and the dicondensation by-product 199.
Scheme 65: Alternative synthesis of spiropyrans and spirooxazines with indolenylium salt 200.
Scheme 66: Synthesis of 4’-substituted spiropyrans 203 by condensation of an acylated methylene indoline 201 w...
Scheme 67: Synthesis of spironaphthopyrans 210 by acid-catalysed condensation of naphthols and diarylpropargyl...
Scheme 68: Photoswitchable surface wettability [194].
Figure 30: Some guiding principles for the choice of the most suitable photoswitch. Note that this guide is ve...
Research progress on calixarene/pillararene-based controlled drug release systems
- Liu-Huan Yi,
- Jian Qin,
- Si-Ran Lu,
- Liu-Pan Yang,
- Li-Li Wang and
- Huan Yao
Beilstein J. Org. Chem. 2025, 21, 1757–1785, doi:10.3762/bjoc.21.139
- characteristics, CAs hold potential for applications in drug delivery systems. 1.2 PAs: structure and properties Since Ogoshi et al. first introduced pillar[n]arenes in 2008, these macrocycles have become essential to the synthetic macrocyclic receptor field [74]. Research on PAs and their derivatives has become
- environment, which significantly enhances the density of π-electrons. This structural feature makes pillar[n]arenes particularly effective at encapsulating guest molecules that are either electron-deficient or neutral. For example, pillar[5]arene (PA5) has a strong binding affinity for neutral guest molecules
- superior performance in host–guest interactions. Creating functional and intelligent supramolecular nano-drug carriers for controlled drug delivery is promising. In this context, water-soluble carboxylated arenes are the primary host molecules for most pH-responsive nanosystems. The nanosystem is broken
Graphical Abstract
Figure 1: Schematic diagram of drug-controlled release mechanisms based on aromatic macrocycles.
Figure 2: Chemical structure of a) calix[n]arene (m = 1,3,5), and b) pillar[n]arene (m = 1,2,3).
Figure 3: Changes in pH conditions cause the release of drugs from CA8 host–guest complexes [101]. Figure 3 was adapted wi...
Figure 4: The illustration of the pH-mediated 1:1 complex formation between the host and guest molecules in a...
Figure 5: Illustration of the pH-responsive self-assembly of mannose-modified CA4 into micelles and the subse...
Figure 6: Illustration of the assembly of supramolecular prodrug nanoparticles from WP6 and DOX-derived prodr...
Figure 7: Illustration of the formation of supramolecular vesicles and their pH-dependent drug release [93]. Figure 7 was...
Figure 8: Schematic illustration of the application of the multifunctional nanoplatform CyCA@POPD in combined...
Figure 9: Illustration of the photolysis of an amphiphilic assembly via CA-induced aggregation [114]. Figure 9 was reprint...
Figure 10: Schematic illustration of drug release controlled by the photo-responsive macroscopic switch based ...
Figure 11: Schematic illustration of the formation process of Azo-SMX and its photoisomerization reaction unde...
Figure 12: Schematic illustration of the enzyme-responsive behavior of supramolecular polymers [95]. Figure 12 was used wit...
Figure 13: Schematic illustration of the amphiphilic assembly of SC4A and its enzyme-responsive applications [119]. ...
Figure 14: Stimuli-responsive nanovalves based on MSNs and choline-SC4A[2]pseudorotaxanes, MSN-C1 with ester-l...
Figure 15: A schematic diagram showing the construction of a supramolecular system by host–guest interaction b...
Figure 16: A schematic diagram showing the formation of the host–guest complex DOX@Biotin-SAC4A by biotin modi...
Figure 17: A schematic diagram showing the self-assembly of CA4 into a hypoxia-responsive peptide hydrogel, wh...
Figure 18: Schematic illustration of the formation process of Lip@GluAC4A and the release of Lip under hypoxic...
Figure 19: Schematic illustration of the construction of a supramolecular vesicle based on the host–guest comp...
Figure 20: Schematic illustration of WP6 self-assembly at pH > 7, and the stimulus-responsive drug release beh...
Figure 21: Schematic illustration of the formation of supramolecular vesicles based on the WP5⊃G super-amphiph...
Figure 22: Schematic illustrations of the host–guest recognition of QAP5⊃SXD, the formation of the nanoparticl...
Figure 23: Schematic illustration of the activation of T-SRNs by acid, alkali, or Zn2+ stimuli to regulate the...
Figure 24: Illustration of the triggered release of BH from CP[5]A@MSNs-Q NPs in response to a drop in pH or a...
Figure 25: Illustration of the supramolecular amphiphiles TPENCn@1 (n = 6 and 12) self-assembling with disulfi...
On the aromaticity and photophysics of 1-arylbenzo[a]imidazo[5,1,2-cd]indolizines as bicolor fluorescent molecules for barium tagging in the study of double-beta decay of 136Xe
- Eric Iván Velazco-Cabral,
- Fernando Auria-Luna,
- Juan Molina-Canteras,
- Miguel A. Vázquez,
- Iván Rivilla and
- Fernando P. Cossío
Beilstein J. Org. Chem. 2025, 21, 1627–1638, doi:10.3762/bjoc.21.126
- decoupling between the para-phenylene and benzo[a]imidazo[5,1,2-cd]indolizine components that results in a blue shift upon Ba2+ coordination. Keywords: aromaticity; DFT-TDDFT calculations; double-beta decay; fluorescent sensors; polycyclic arenes; Introduction Double beta-decay [1] is a radioactive decay
Graphical Abstract
Figure 1: Two possible double beta decay modes. Left: with emission of two electronic antineutrinos (ββ2ν). R...
Figure 2: General structure of first-generation bicolor fluorescent indicators based on 1-aryl benzo[a]imidaz...
Scheme 1: Hyperhomodesmotic equations used to analyze the resonance energy of benzo[a]imidazo[5,1,2-cd]indoli...
Figure 3: (A) Total, peripheral and modular delocalization patterns for fluorophore 1. The ground state (So) ...
Scheme 2: Isodesmic (A) and reaction profiles (B) for the analysis of the interaction of Ba2+ with different ...
Figure 4: Fully optimized geometries (B3LYP-D3BJ/6ccrow-311++G**&DefTZVPP(Ba) level of theory) of Ba2+·crown ...
Figure 5: Relaxed scan of the relative conformational energies of sensor 18 at the free state (A) and bound t...
Scheme 3: Reaction of fluorescent probe 18 with barium perchlorate, as indicated in Figure 2 (X = O, Y, Z = Me). The ...
Figure 6: Fully optimized structures (B3LYP-D3BJ/6-311++G(d,p)&DefTZVPP(Ba) level of theory) of compounds 18 ...
Figure 7: Comparison between the calculated and experimental differences between the emission wavelength of 18...
3-Aryl-2H-azirines as annulation reagents in the Ni(II)-catalyzed synthesis of 1H-benzo[4,5]thieno[3,2-b]pyrroles
- Julia I. Pavlenko,
- Pavel A. Sakharov,
- Anastasiya V. Agafonova,
- Derenik A. Isadzhanyan,
- Alexander F. Khlebnikov and
- Mikhail S. Novikov
Beilstein J. Org. Chem. 2025, 21, 1595–1602, doi:10.3762/bjoc.21.123
- arenes with azirines. These include the [3 + 2] cycloaddition of azirines to arynes (Scheme 1, reaction 1) [10][11][12], Pd-catalyzed reaction of azirines with iodoarenes (Scheme 1, reaction 2) [13], and reaction of 2-aroylazirines with naphthols (Scheme 1, reaction 3) [8]. The [3 + 2] annulation
Graphical Abstract
Scheme 1: Synthesis of fused pyrroles and azoles by [3 + 2] annulation reactions of azirines.
Scheme 2: Synthesis of benzo[4,5]thieno[3,2-b]pyrroles 3.
Scheme 3: Plausible mechanism for the formation of compounds 3.
Scheme 4: Post-modifications of 1H-benzo[4,5]thieno[3,2-b]pyrrole (3b).
Scheme 5: Synthesis of pyrrolo[3,2-b]indole 10.
Scheme 6: IPrCuCl-catalyzed reactions of indoles 9b,c with azirine 2a.
Scheme 7: Ni(II)- and Cu(I)-catalyzed reactions of indole 15 with azirine 2a.
Oxetanes: formation, reactivity and total syntheses of natural products
- Peter Gabko,
- Martin Kalník and
- Maroš Bella
Beilstein J. Org. Chem. 2025, 21, 1324–1373, doi:10.3762/bjoc.21.101
- )aryloxetanes 146 in moderate yields. Investigation of the reaction scope identified electron-rich, -neutral and -poor arenes as well as vinyl bromides as viable coupling partners, and the authors also applied this methodology for a novel, simplified synthesis of two medicinally relevant oxetane precursors. The
Graphical Abstract
Figure 1: Bond lengths and bond angles in oxetane at 140 K [2].
Figure 2: Analogy of 3-substituted oxetanes to carbonyl and gem-dimethyl groups [12].
Figure 3: Use of oxetanes in drug design – selected examples.
Figure 4: Examples of oxetane-containing natural products.
Scheme 1: Synthetic strategies towards construction of the oxetane ring.
Scheme 2: Overview of intramolecular Williamson etherification and competing Grob fragmentation.
Scheme 3: Synthesis of spiro-oxetanes via 1,4-C–H insertion and Williamson etherification.
Scheme 4: Use of phenyl vinyl selenone in the synthesis of spirooxindole oxetanes.
Scheme 5: Synthesis of bicyclic 3,5-anhydrofuranoses via double epoxide opening/etherification.
Scheme 6: Preparation of spirooxetanes by cycloisomerisation via MHAT/RPC.
Scheme 7: Oxetane synthesis via alcohol C–H functionalisation.
Scheme 8: Access to oxetanes 38 from α-acetyloxy iodides.
Scheme 9: The kilogram-scale synthesis of oxetane intermediate 41.
Scheme 10: Overview of the intramolecular opening of 3-membered rings.
Scheme 11: Synthesis of 4,7-dioxatricyclo[3.2.1.03,6]octane skeletons.
Scheme 12: Silicon-directed electrophilic cyclisation of homoallylic alcohols.
Scheme 13: Hydrosilylation–iodocyclisation of homopropargylic alcohols.
Scheme 14: Cu-catalysed intramolecular O-vinylation of γ-bromohomoallylic alcohols.
Scheme 15: Cu-catalysed intramolecular cross-coupling of hydroxyvinylstannanes.
Scheme 16: Isomerisation of oxiranyl ethers containing weakly carbanion-stabilising groups.
Scheme 17: Cyclisation of diethyl haloalkoxymalonates.
Scheme 18: Synthesis of oxetanes through a 1,5-HAT/radical recombination sequence.
Scheme 19: General approach to oxetanes via [2 + 2] cycloadditions.
Scheme 20: Synthesis of tricyclic 4:4:4 oxetanes through a photochemical triple cascade reaction.
Scheme 21: Iridium-catalysed Paternò–Büchi reaction between α-ketoesters and simple alkenes.
Scheme 22: Three-step synthesis of spirocyclic oxetanes 83 via Paternò–Büchi reaction, nucleophilic ring openi...
Scheme 23: Enantioselective Paternò–Büchi reaction catalysed by a chiral iridium photocatalyst.
Scheme 24: Synthesis of polysubstituted oxetanes 92 via Cu(II)-mediated formal [2 + 2] cycloadditions.
Scheme 25: Synthesis of alkylideneoxetanes via NHC- and DBU-mediated formal [2 + 2] cycloadditions.
Scheme 26: Use of sulphur-stabilised carbanions in ring expansions.
Scheme 27: Synthesis of α,α-difluoro(arylthio)methyl oxetanes.
Scheme 28: Ring expansion in an industrial synthesis of PF-06878031.
Scheme 29: Ring contraction of triflated 2-hydroxy-γ-lactones.
Scheme 30: Ring contraction in an industrial synthesis of PF-06878031.
Scheme 31: Photochemical ring contraction of 2,5-dihydrofurans by aryldiazoacetic acid esters.
Scheme 32: Synthesis of 3-oxetanones via O-H insertion of carbenes.
Scheme 33: Synthesis of phosphonate oxetanones via gold-mediated alkyne oxidation/O–H insertion.
Scheme 34: Syntheses and common derivatisations of 3-oxetanone.
Scheme 35: SN1 substitution of 3-aryloxetan-3-ols by thiols and alcohols.
Scheme 36: Fe–Ni dual-catalytic olefin hydroarylation towards 3-alkyl-3-(hetero)aryloxetanes.
Scheme 37: Synthesis of 3-aryloxetan-3-carboxylic acids.
Scheme 38: Decarboxylative alkylation of 3-aryloxetan-3-carboxylic acids.
Scheme 39: Synthesis of 3-amino-3-aryloxetanes via photoredox/nickel cross-coupling catalysis.
Scheme 40: Intermolecular cross-selective [2 + 2] photocycloaddition towards spirooxetanes.
Scheme 41: Synthesis of 3-aryl-3-aminooxetanes via defluorosulphonylative coupling.
Scheme 42: Two-step synthesis of amide bioisosteres via benzotriazolyl Mannich adducts 170.
Scheme 43: Functionalisation of oxetanyl trichloroacetimidates 172.
Scheme 44: Synthesis of oxetane-amino esters 176.
Scheme 45: Tandem Friedel–Crafts alkylation/intramolecular ring opening of 3-aryloxetan-3-ols.
Scheme 46: Synthesis of polysubstituted furans and pyrroles.
Scheme 47: Synthesis of oxazolines and bisoxazolines.
Scheme 48: Tandem, one-pot syntheses of various polycyclic heterocycles.
Scheme 49: Synthesis of 1,2-dihydroquinolines via skeletal reorganisation of oxetanes.
Scheme 50: Synthesis of benzoindolines and 2,3-dihydrobenzofurans and their derivatisations.
Scheme 51: Synthesis of polysubstituted 1,4-dioxanes.
Scheme 52: Preparation of various lactones via ring opening of oxetane-carboxylic acids 219.
Scheme 53: Tsuji-Trost allylation/ring opening of 3-aminooxetanes.
Scheme 54: Arylative skeletal rearrangement of 3-vinyloxetan-3-ols to 2,5-dihydrofurans.
Scheme 55: Reductive opening of oxetanes using catalytic Mg–H species.
Scheme 56: Opening of oxetanes by silyl ketene acetals.
Scheme 57: Rhodium-catalysed hydroacylation of oxetanes.
Scheme 58: Generation of radicals from oxetanes mediated by a vitamin B12-derived cobalt catalyst.
Scheme 59: Reductive opening of oxetanes by B–Si frustrated Lewis pairs.
Scheme 60: Zirconocene-mediated reductive opening of oxetanes.
Scheme 61: Enantioselective syntheses of small and medium-size rings using chiral phosphoric acids.
Scheme 62: Asymmetric synthesis of 2,3-dihydrobenzo[b]oxepines catalysed by a chiral scandium complex.
Scheme 63: Enantioselective synthesis of 1,3-bromohydrins under a chiral squaramide catalysis.
Scheme 64: Enantioselective opening of 2-aryl-2-ethynyloxetanes by anilines.
Scheme 65: Ru-catalysed insertion of diazocarbonyls into oxetanes.
Scheme 66: Ring expansion of oxetanes by stabilised carbenes generated under blue light irradiation.
Scheme 67: Expansion of oxetanes via nickel-catalysed insertion of alkynyltrifluoroborates.
Scheme 68: Nickel-catalysed expansion of oxetanes into ε-caprolactones.
Scheme 69: Expansion of oxetanes via cobalt-catalysed carbonyl insertion.
Scheme 70: Gold-catalysed intramolecular 1,1-carboalkoxylation of oxetane-ynamides.
Scheme 71: Expansion of oxetanes by stabilised sulphoxonium ylides.
Scheme 72: Cu-catalysed ring expansion of 2-vinyloxetanes by diazoesters.
Scheme 73: Total synthesis of (+)-oxetin.
Scheme 74: Total synthesis of racemic oxetanocin A.
Scheme 75: Total synthesis of (−)-merrilactone A.
Scheme 76: Total synthesis of (+)-dictyoxetane.
Scheme 77: Total synthesis of ent-dichrocephone B.
Scheme 78: Total synthesis of (−)-mitrephorone A.
Scheme 79: Total synthesis of (−)-taxol.
Recent advances in oxidative radical difunctionalization of N-arylacrylamides enabled by carbon radical reagents
- Jiangfei Chen,
- Yi-Lin Qu,
- Ming Yuan,
- Xiang-Mei Wu,
- Heng-Pei Jiang,
- Ying Fu and
- Shengrong Guo
Beilstein J. Org. Chem. 2025, 21, 1207–1271, doi:10.3762/bjoc.21.98
Graphical Abstract
Scheme 1: DTBP-mediated oxidative alkylarylation of activated alkenes.
Scheme 2: Iron-catalyzed oxidative 1,2-alkylarylation.
Scheme 3: Possible mechanism for the iron-catalyzed oxidative 1,2-alkylation of activated alkenes.
Scheme 4: A metal-free strategy for synthesizing 3,3-disubstituted oxindoles.
Scheme 5: Iminoxyl radical-promoted cascade oxyalkylation/alkylarylation of alkenes.
Scheme 6: Proposed mechanism for the iminoxyl radical-promoted cascade oxyalkylation/alkylarylation of alkene...
Scheme 7: Bicyclization of 1,n-enynes with alkyl nitriles.
Scheme 8: Possible reaction mechanism for the bicyclization of 1,n-enynes with alkyl nitriles.
Scheme 9: Radical cyclization of N-arylacrylamides with isocyanides.
Scheme 10: Plausible mechanism for the radical cyclization of N-arylacrylamides with isocyanides.
Scheme 11: Electrochemical dehydrogenative cyclization of 1,3-dicarbonyl compounds.
Scheme 12: Plausible mechanism for the dehydrogenative cyclization of 1,3-dicarbonyl compounds.
Scheme 13: Photocatalyzed cyclization of N-arylacrylamide and N,N-dimethylaniline.
Scheme 14: Proposed mechanism for the photocatalyzed cyclization of N-arylacrylamides and N,N-dimethylanilines....
Scheme 15: Electrochemical monofluoroalkylation cyclization of N-arylacrylamides with dimethyl 2-fluoromalonat...
Scheme 16: Proposed mechanism for the electrochemical radical cyclization of N-arylacrylamides with dimethyl 2...
Scheme 17: Photoelectrocatalytic carbocyclization of unactivated alkenes using simple malonates.
Scheme 18: Plausible mechanism for the photoelectrocatalytic carbocyclization of unactivated alkenes with simp...
Scheme 19: Bromide-catalyzed electrochemical trifluoromethylation/cyclization of N-arylacrylamides.
Scheme 20: Proposed mechanism for the electrochemical trifluoromethylation/cyclization of N-arylacrylamides.
Scheme 21: Visible light-mediated trifluoromethylarylation of N-arylacrylamides.
Scheme 22: Plausible reaction mechanism for the visible light-mediated trifluoromethylarylation of N-arylacryl...
Scheme 23: Electrochemical difluoroethylation cyclization of N-arylacrylamides with sodium difluoroethylsulfin...
Scheme 24: Electrochemical difluoroethylation cyclization of N-methyacryloyl-N-alkylbenzamides with sodium dif...
Scheme 25: Photoredox-catalyzed radical aryldifluoromethylation of N-arylacrylamides with S-(difluoromethyl)su...
Scheme 26: Proposed mechanism for the photoredox-catalyzed radical aryldifluoromethylation of N-arylacrylamide...
Scheme 27: Visible-light-induced domino difluoroalkylation/cyclization of N-cyanamide alkenes.
Scheme 28: Proposed mechanism of photoredox-catalyzed radical domino difluoroalkylation/cyclization of N-cyana...
Scheme 29: Palladium-catalyzed oxidative difunctionalization of alkenes.
Scheme 30: Two possible mechanisms of palladium-catalyzed oxidative difunctionalization.
Scheme 31: Silver-catalyzed oxidative 1,2-alkyletherification of unactivated alkenes with α-bromoalkylcarbonyl...
Scheme 32: Photochemical radical cascade cyclization of dienes.
Scheme 33: Proposed mechanism for the photochemical radical cascade 6-endo cyclization of dienes with α-carbon...
Scheme 34: Photocatalyzed radical coupling/cyclization of N-arylacrylamides and.
Scheme 35: Photocatalyzed radical-type couplings/cyclization of N-arylacrylamides with sulfoxonium ylides.
Scheme 36: Possible mechanism of visible-light-induced radical-type couplings/cyclization of N-arylacrylamides...
Scheme 37: Visible-light-promoted difluoroalkylated oxindoles systhesis via EDA complexes.
Scheme 38: Possible mechanism for the visible-light-promoted radical cyclization of N-arylacrylamides with bro...
Scheme 39: A dicumyl peroxide-initiated radical cascade reaction of N-arylacrylamide with DCM.
Scheme 40: Possible mechanism of radical cyclization of N-arylacrylamides with DCM.
Scheme 41: An AIBN-mediated radical cascade reaction of N-arylacrylamides with perfluoroalkyl iodides.
Scheme 42: Possible mechanism for the reaction with perfluoroalkyl iodides.
Scheme 43: Photoinduced palladium-catalyzed radical annulation of N-arylacrylamides with alkyl halides.
Scheme 44: Radical alkylation/cyclization of N-Alkyl-N-methacryloylbenzamides with alkyl halides.
Scheme 45: Possible mechanism for the alkylation/cyclization with unactivated alkyl chlorides.
Scheme 46: Visible-light-driven palladium-catalyzed radical cascade cyclization of N-arylacrylamides with unac...
Scheme 47: NHC-catalyzed radical cascade cyclization of N-arylacrylamides with alkyl bromides.
Scheme 48: Possible mechanism of NHC-catalyzed radical cascade cyclization.
Scheme 49: Electrochemically mediated radical cyclization reaction of N-arylacrylamides with freon-type methan...
Scheme 50: Proposed mechanistic pathway of electrochemically induced radical cyclization reaction.
Scheme 51: Redox-neutral photoinduced radical cascade cylization of N-arylacrylamides with unactivated alkyl c...
Scheme 52: Proposed mechanistic hypothesis of redox-neutral radical cascade cyclization.
Scheme 53: Thiol-mediated photochemical radical cascade cylization of N-arylacrylamides with aryl halides.
Scheme 54: Proposed possible mechanism of thiol-mediated photochemical radical cascade cyclization.
Scheme 55: Visible-light-induced radical cascade bromocyclization of N-arylacrylamides with NBS.
Scheme 56: Possible mechanism of visible-light-induced radical cascade cyclization.
Scheme 57: Decarboxylation/radical C–H functionalization by visible-light photoredox catalysis.
Scheme 58: Plausible mechanism of visible-light photoredox-catalyzed radical cascade cyclization.
Scheme 59: Visible-light-promoted tandem radical cyclization of N-arylacrylamides with N-(acyloxy)phthalimides....
Scheme 60: Plausible mechanism for the tandem radical cyclization reaction.
Scheme 61: Visible-light-induced aerobic radical cascade alkylation/cyclization of N-arylacrylamides with alde...
Scheme 62: Plausible mechanism for the aerobic radical alkylarylation of electron-deficient amides.
Scheme 63: Oxidative decarbonylative [3 + 2]/[5 + 2] annulation of N-arylacrylamide with vinyl acids.
Scheme 64: Plausible mechanism for the decarboxylative (3 + 2)/(5 + 2) annulation between N-arylacrylamides an...
Scheme 65: Rhenium-catalyzed alkylarylation of alkenes with PhI(O2CR)2.
Scheme 66: Plausible mechanism for the rhenium-catalyzed decarboxylative annulation of N-arylacrylamides with ...
Scheme 67: Visible-light-induced one-pot tandem reaction of N-arylacrylamides.
Scheme 68: Plausible mechanism for the visible-light-initiated tandem synthesis of difluoromethylated oxindole...
Scheme 69: Copper-catalyzed redox-neutral cyanoalkylarylation of activated alkenes with cyclobutanone oxime es...
Scheme 70: Plausible mechanism for the copper-catalyzed cyanoalkylarylation of activated alkenes.
Scheme 71: Photoinduced alkyl/aryl radical cascade for the synthesis of quaternary CF3-attached oxindoles.
Scheme 72: Plausible photoinduced electron-transfer (PET) mechanism.
Scheme 73: Photoinduced cerium-mediated decarboxylative alkylation cascade cyclization.
Scheme 74: Plausible reaction mechanism for the decarboxylative radical-cascade alkylation/cyclization.
Scheme 75: Metal-free oxidative tandem coupling of activated alkenes.
Scheme 76: Control experiments and possible mechanism for 1,2-carbonylarylation of alkenes with carbonyl C(sp2...
Scheme 77: Silver-catalyzed acyl-arylation of activated alkenes with α-oxocarboxylic acids.
Scheme 78: Proposed mechanism for the decarboxylative acylarylation of acrylamides.
Scheme 79: Visible-light-mediated tandem acylarylation of olefines with carboxylic acids.
Scheme 80: Proposed mechanism for the radical cascade cyclization with acyl radical via visible-light photored...
Scheme 81: Erythrosine B-catalyzed visible-light photoredox arylation-cyclization of N-arylacrylamides with ar...
Scheme 82: Electrochemical cobalt-catalyzed radical cyclization of N-arylacrylamides with arylhydrazines or po...
Scheme 83: Proposed mechanism of radical cascade cyclization via electrochemical cobalt catalysis.
Scheme 84: Copper-catalyzed oxidative tandem carbamoylation/cyclization of N-arylacrylamides with hydrazinecar...
Scheme 85: Proposed reaction mechanism for the radical cascade cyclization by copper catalysis.
Scheme 86: Visible-light-driven radical cascade cyclization reaction of N-arylacrylamides with α-keto acids.
Scheme 87: Proposed mechanism of visible-light-driven cascade cyclization reaction.
Scheme 88: Peroxide-induced radical carbonylation of N-(2-methylallyl)benzamides with methyl formate.
Scheme 89: Proposed cyclization mechanism of peroxide-induced radical carbonylation with N-(2-methylallyl)benz...
Scheme 90: Persulfate promoted carbamoylation of N-arylacrylamides and N-arylcinnamamides.
Scheme 91: Proposed mechanism for the persulfate promoted radical cascade cyclization reaction of N-arylacryla...
Scheme 92: Photocatalyzed carboacylation with N-arylpropiolamides/N-alkyl acrylamides.
Scheme 93: Plausible mechanism for the photoinduced carboacylation of N-arylpropiolamides/N-alkyl acrylamides.
Scheme 94: Electrochemical Fe-catalyzed radical cyclization with N-arylacrylamides.
Scheme 95: Plausible mechanism for the electrochemical Fe-catalysed radical cyclization of N-phenylacrylamide.
Scheme 96: Substrate scope of the selective functionalization of various α-ketoalkylsilyl peroxides with metha...
Scheme 97: Proposed reaction mechanism for the Fe-catalyzed reaction of alkylsilyl peroxides with methacrylami...
Scheme 98: EDA-complex mediated C(sp2)–C(sp3) cross-coupling of TTs and N-methyl-N-phenylmethacrylamides.
Scheme 99: Proposed mechanism for the synthesis of oxindoles via EDA complex.
Selective monoformylation of naphthalene-fused propellanes for methylene-alternating copolymers
- Kenichi Kato,
- Tatsuki Hiroi,
- Seina Okada,
- Shunsuke Ohtani and
- Tomoki Ogoshi
Beilstein J. Org. Chem. 2025, 21, 1183–1191, doi:10.3762/bjoc.21.95
- widely adopted to improve the solubility and modulate the molecular assemblies [4][5][6][7][8][9]. By contrast, the presence of sp3-hybridized atoms in core π-skeletons can lead to three-dimensional (3D) structures with appropriate rigidity, thereby giving macrocyclic arenes [10][11], molecule-based
Graphical Abstract
Figure 1: Chemical structures of fully π-fused propellanes and their typical reaction patterns toward electro...
Figure 2: a) Synthesis of methylene-alternating copolymers of fully π-fused propellanes. DCE, 1,2-dichloroeth...
Figure 3: Gas adsorption (filled circles) and desorption (open circles) isotherms of [3.3.3]_oligo (dark red)...
Recent advances in synthetic approaches for bioactive cinnamic acid derivatives
- Betty A. Kustiana,
- Galuh Widiyarti and
- Teni Ernawati
Beilstein J. Org. Chem. 2025, 21, 1031–1086, doi:10.3762/bjoc.21.85
Graphical Abstract
Figure 1: Biologically active cinnamic acid derivatives.
Scheme 1: General synthetic strategies for cinnamic acid derivatizations.
Scheme 2: Cinnamic acid coupling via isobutyl anhydride formation.
Scheme 3: Amidation reaction via O/N-pivaloyl activation.
Scheme 4: Cinnamic acid amidation using TCCA/PPh3 reagent.
Scheme 5: Cinnamic acid amidation using triazine-based reagents.
Scheme 6: Cinnamic acid amidation using continuous flow mechanochemistry.
Scheme 7: Cinnamic acid amidation using COMU as coupling reagent.
Scheme 8: Cinnamic acid amidation using allenone coupling reagent.
Scheme 9: Cinnamic acid amidation using 4-acetamidophenyl triflimide as reagent.
Scheme 10: Cinnamic acid amidation using methyltrimethoxysilane (MTM).
Scheme 11: Cinnamic acid amidation utilizing amine–borane reagent.
Scheme 12: Cinnamic acid amidation using TCCA/PPh3 reagent.
Scheme 13: Cinnamic acid amidation using PPh3/I2 reagent.
Scheme 14: Cinnamic acid amidation using PCl3 reagent.
Scheme 15: Cinnamic acid amidation utilizing pentafluoropyridine (PFP) as reagent.
Scheme 16: Cinnamic acid amidation using hypervalent iodine(III).
Scheme 17: Mechanochemical amidation using 1,1,2,2-tetrafluoroethyl-N,N-dimethylamine (TFEDMA) reagent.
Scheme 18: Methyl ester preparation using tris(2,4,6-trimethoxyphenyl)phosphine (TMPP).
Scheme 19: N-Trifluoromethyl amide preparation using isothiocyanate and AgF.
Scheme 20: POCl3-mediated amide coupling of carboxylic acid and DMF.
Scheme 21: O-Alkylation of cinnamic acid using alkylating agents.
Scheme 22: Glycoside preparation via Mitsunobu reaction.
Scheme 23: O/N-Acylation via rearrangement reactions.
Scheme 24: Amidation reactions using sulfur-based alkylating agents.
Scheme 25: Amidation reaction catalyzed by Pd0 via C–N cleavage.
Scheme 26: Amidation reaction catalyzed by CuCl/PPh3.
Scheme 27: Cu(II) triflate-catalyzed N-difluoroethylimide synthesis.
Scheme 28: Cu/Selectfluor-catalyzed transamidation reaction.
Scheme 29: CuO–CaCO3-catalyzed amidation reaction.
Scheme 30: Ni-catalyzed reductive amidation.
Scheme 31: Lewis acidic transition-metal-catalyzed O/N-acylations.
Scheme 32: Visible-light-promoted amidation of cinnamic acid.
Scheme 33: Sunlight/LED-promoted amidation of cinnamic acid.
Scheme 34: Organophotocatalyst-promoted N–O cleavage of Weinreb amides to synthesize primary amides.
Scheme 35: Cinnamamide synthesis through [Ir] photocatalyst-promoted C–N-bond cleavage of tertiary amines.
Scheme 36: Blue LED-promoted FeCl3-catalyzed reductive transamidation.
Scheme 37: FPyr/TCT-catalyzed amidation of cinnamic acid derivative 121.
Scheme 38: Cs2CO3/DMAP-mediated esterification.
Scheme 39: HBTM organocatalyzed atroposelective N-acylation.
Scheme 40: BH3-catalyzed N-acylation reactions.
Scheme 41: Borane-catalyzed N-acylation reactions.
Scheme 42: Catalytic N-acylation reactions via H/F bonding activation.
Scheme 43: Brønsted base-catalyzed synthesis of cinnamic acid esters.
Scheme 44: DABCO/Fe3O4-catalyzed N-methyl amidation of cinnamic acid 122.
Scheme 45: Catalytic oxidation reactions of acylating agents.
Scheme 46: Preparation of cinnamamide-substituted benzocyclooctene using I(I)/I(III) catalysis.
Scheme 47: Pd-colloids-catalyzed oxidative esterification of cinnamyl alcohol.
Scheme 48: Graphene-supported Pd/Au alloy-catalyzed oxidative esterification via hemiacetal intermediate.
Scheme 49: Au-supported on A) carbon nanotubes (CNT) and B) on porous boron nitride (pBN) as catalyst for the ...
Scheme 50: Cr-based catalyzed oxidative esterification of cinnamyl alcohols with H2O2 as the oxidant.
Scheme 51: Co-based catalysts used for oxidative esterification of cinnamyl alcohol.
Scheme 52: Iron (A) and copper (B)-catalyzed oxidative esterification of cinnamaldehyde.
Scheme 53: NiHPMA-catalyzed oxidative esterification of cinnamaldehyde.
Scheme 54: Synthesis of cinammic acid esters through NHC-catalyzed oxidative esterification via intermolecular...
Scheme 55: Redox-active NHC-catalyzed esterification via intramolecular oxidation.
Scheme 56: Electrochemical conversion of cinnamaldehyde to methyl cinnamate.
Scheme 57: Bu4NI/TBHP-catalyzed synthesis of bisamides from cinnamalaldehyde N-tosylhydrazone.
Scheme 58: Zn/NC-950-catalyzed oxidative esterification of ketone 182.
Scheme 59: Ru-catalyzed oxidative carboxylation of terminal alkenes.
Scheme 60: Direct carboxylation of alkenes using CO2.
Scheme 61: Carboxylation of alkenylboronic acid/ester.
Scheme 62: Carboxylation of gem-difluoroalkenes with CO2.
Scheme 63: Photoredox-catalyzed carboxylation of difluoroalkenes.
Scheme 64: Ru-catalyzed carboxylation of alkenyl halide.
Scheme 65: Carboxylation of alkenyl halides under flow conditions.
Scheme 66: Cinnamic acid ester syntheses through carboxylation of alkenyl sulfides/sulfones.
Scheme 67: Cinnamic acid derivatives synthesis through a Ag-catalyzed decarboxylative cross-coupling proceedin...
Scheme 68: Pd-catalyzed alkyne hydrocarbonylation.
Scheme 69: Fe-catalyzed alkyne hydrocarbonylation.
Scheme 70: Alkyne hydrocarboxylation using CO2.
Scheme 71: Alkyne hydrocarboxylation using HCO2H as CO surrogate.
Scheme 72: Co/AlMe3-catalyzed alkyne hydrocarboxylation using DMF.
Scheme 73: Au-catalyzed oxidation of Au–allenylidenes.
Scheme 74: Pd-catalyzed C–C-bond activation of cyclopropenones to synthesize unsaturated esters and amides.
Scheme 75: Ag-catalyzed C–C-bond activation of diphenylcyclopropenone.
Scheme 76: Cu-catalyzed C–C bond activation of diphenylcyclopropenone.
Scheme 77: PPh3-catalyzed C–C-bond activation of diphenylcyclopropenone.
Scheme 78: Catalyst-free C–C-bond activation of diphenylcyclopropenone.
Scheme 79: Cu-catalyzed dioxolane cleavage.
Scheme 80: Multicomponent coupling reactions.
Scheme 81: Pd-catalyzed partial hydrogenation of electrophilic alkynes.
Scheme 82: Nickel and cobalt as earth-abundant transition metals used as catalysts for the partial hydrogenati...
Scheme 83: Metal-free-catalyzed partial hydrogenation of conjugated alkynes.
Scheme 84: Horner–Wadsworth–Emmons reaction between triethyl 2-fluoro-2-phosphonoacetate and aldehydes with ei...
Scheme 85: Preparation of E/Z-cinnamates using thiouronium ylides.
Scheme 86: Transition-metal-catalyzed ylide reactions.
Scheme 87: Redox-driven ylide reactions.
Scheme 88: Noble transition-metal-catalyzed olefination via carbenoid species.
Scheme 89: TrBF4-catalyzed olefination via carbene species.
Scheme 90: Grubbs catalyst (cat 7)/photocatalyst-mediated metathesis reactions.
Scheme 91: Elemental I2-catalyzed carbonyl-olefin metathesis.
Scheme 92: Cu-photocatalyzed E-to-Z isomerization of cinnamic acid derivatives.
Scheme 93: Ni-catalyzed E-to-Z isomerization.
Scheme 94: Dehydration of β-hydroxy esters via an E1cB mechanism to access (E)-cinnamic acid esters.
Scheme 95: Domino ring-opening reaction induced by a base.
Scheme 96: Dehydroamination of α-aminoester derivatives.
Scheme 97: Accessing methyl cinnamate (44) via metal-free deamination or decarboxylation.
Scheme 98: The core–shell magnetic nanosupport-catalyzed condensation reaction.
Scheme 99: Accessing cinnamic acid derivatives from acetic acid esters/amides through α-olefination.
Scheme 100: Accessing cinnamic acid derivatives via acceptorless α,β-dehydrogenation.
Scheme 101: Cu-catalyzed formal [3 + 2] cycloaddition.
Scheme 102: Pd-catalyzed C–C bond formation via 1,4-Pd-shift.
Scheme 103: NHC-catalyzed Rauhut–Currier reactions.
Scheme 104: Heck-type reaction for Cα arylation.
Scheme 105: Cu-catalyzed trifluoromethylation of cinnamamide.
Scheme 106: Ru-catalyzed alkenylation of arenes using directing groups.
Scheme 107: Earth-abundant transition-metal-catalyzed hydroarylation of α,β-alkynyl ester 374.
Scheme 108: Precious transition-metal-catalyzed β-arylation of cinnamic acid amide/ester.
Scheme 109: Pd-catalyzed β-amination of cinnamamide.
Scheme 110: S8-mediated β-amination of methyl cinnamate (44).
Scheme 111: Pd-catalyzed cross-coupling reaction of alkynyl esters with phenylsilanes.
Scheme 112: Pd-catalyzed β-cyanation of alkynyl amide/ester.
Scheme 113: Au-catalyzed β-amination of alkynyl ester 374.
Scheme 114: Metal-free-catalyzed Cβ-functionalizations of alkynyl esters.
Scheme 115: Heck-type reactions.
Scheme 116: Mizoroki–Heck coupling reactions using unconventional functionalized arenes.
Scheme 117: Functional group-directed Mizoroki–Heck coupling reactions.
Scheme 118: Pd nanoparticles-catalyzed Mizoroki–Heck coupling reactions.
Scheme 119: Catellani-type reactions to access methyl cinnamate with multifunctionalized arene.
Scheme 120: Multicomponent coupling reactions.
Scheme 121: Single atom Pt-catalyzed Heck coupling reaction.
Scheme 122: Earth-abundant transition metal-catalyzed Heck coupling reactions.
Scheme 123: Polymer-coated earth-abundant transition metals-catalyzed Heck coupling reactions.
Scheme 124: Earth-abundant transition-metal-based nanoparticles as catalysts for Heck coupling reactions.
Scheme 125: CN- and Si-based directing groups to access o-selective cinnamic acid derivatives.
Scheme 126: Amide-based directing group to access o-selective cinnamic acid derivatives.
Scheme 127: Carbonyl-based directing group to access o-selective cinnamic acid derivatives.
Scheme 128: Stereoselective preparation of atropisomers via o-selective C(sp2)–H functionalization.
Scheme 129: meta-Selective C(sp2)–H functionalization using directing group-tethered arenes.
Scheme 130: para-Selective C(sp2)–H functionalization using directing group-tethered arenes.
Scheme 131: Non-directed C(sp2)–H functionalization via electrooxidative Fujiwara–Moritani reaction.
Scheme 132: Interconversion of functional groups attached to cinnamic acid.
Scheme 133: meta-Selective C(sp2)–H functionalization of cinnamate ester.
Scheme 134: C(sp2)–F arylation using Grignard reagents.
Scheme 135: Truce–Smiles rearrangement of N-aryl metacrylamides.
Scheme 136: Phosphine-catalyzed cyclization of γ-vinyl allenoate with enamino esters.
Recent total synthesis of natural products leveraging a strategy of enamide cyclization
- Chun-Yu Mi,
- Jia-Yuan Zhai and
- Xiao-Ming Zhang
Beilstein J. Org. Chem. 2025, 21, 999–1009, doi:10.3762/bjoc.21.81
- tertiary enamides is employed. Inspired by Wang’s earlier work, Zhang and Tu’s group developed a tandem cyclization/Mannich reaction to construct this architecture [35]. However, unlike the electron-rich arenes, the use of silyl enol ethers to terminate the second cyclization of the acyliminium
Graphical Abstract
Figure 1: Reactivity of enamides and enamide cyclizations.
Scheme 1: Total synthesis of (−)-dihydrolycopodine and (−)-lycopodine.
Scheme 2: Collective total synthesis of fawcettimine-type alkaloids.
Scheme 3: Total syntheses of cephalotaxine and cephalezomine H.
Scheme 4: Collective total syntheses of Cephalotaxus alkaloids.
Scheme 5: Asymmetric tandem cyclization/Pictet–Spengler reaction of tertiary enamides.
Scheme 6: Tandem cyclization/Pictet–Spengler reaction for the synthesis of chiral tetracyclic compounds.
Scheme 7: Total synthesis of (−)-cephalocyclidin A.
Recent advances in controllable/divergent synthesis
- Jilei Cao,
- Leiyang Bai and
- Xuefeng Jiang
Beilstein J. Org. Chem. 2025, 21, 890–914, doi:10.3762/bjoc.21.73
- pathway bifurcated based on the steric demands of Si–C-bond activation. The methyl-substituted ligand (S)-8H-binaphthyl phosphoramidite L4, featuring a spacious cavity, favored sterically encumbered Si–C(sp3)-bond activation, selectively delivering axially chiral (S)-1-silacyclohexenyl arenes 17 with high
Graphical Abstract
Scheme 1: Ligand-controlled regiodivergent C1 insertion into arynes [19].
Scheme 2: Ligand effect in homogenous gold catalysis enabling regiodivergent π-bond-activated cyclization [20].
Scheme 3: Ligand-controlled palladium(II)-catalyzed regiodivergent carbonylation of alkynes [21].
Scheme 4: Catalyst-controlled annulations of strained cyclic allenes with π-allyl palladium complexes and pro...
Scheme 5: Ring expansion of benzosilacyclobutenes with alkynes [23].
Scheme 6: Photoinduced regiodivergent and enantioselective cross-coupling [24].
Scheme 7: Catalyst-controlled regiodivergent and enantioselective formal hydroamination of N,N-disubstituted ...
Scheme 8: Catalyst-tuned regio- and enantioselective C(sp3)–C(sp3) coupling [31].
Scheme 9: Catalyst-controlled annulations of bicyclo[1.1.0]butanes with vinyl azides [32].
Scheme 10: Solvent-driven reversible macrocycle-to-macrocycle interconversion [39].
Scheme 11: Unexpected solvent-dependent reactivity of cyclic diazo imides and mechanism [40].
Scheme 12: Palladium-catalyzed annulation of prochiral N-arylphosphonamides with aromatic iodides [41].
Scheme 13: Time-dependent enantiodivergent synthesis [42].
Scheme 14: Time-controlled palladium-catalyzed divergent synthesis of silacycles via C–H activation [43].
Scheme 15: Proposed mechanism for the time-controlled palladium-catalyzed divergent synthesis of silacycles [43].
Scheme 16: Metal-free temperature-controlled regiodivergent borylative cyclizations of enynes [45].
Scheme 17: Nickel-catalyzed switchable site-selective alkene hydroalkylation by temperature regulation [46].
Scheme 18: Copper-catalyzed decarboxylative amination/hydroamination sequence [48].
Scheme 19: Proposed mechanism of copper-catalyzed decarboxylative amination/hydroamination sequence [48].
Scheme 20: Enantioselective chemodivergent three-component radical tandem reactions [49].
Scheme 21: Substrate-controlled synthesis of indoles and 3H-indoles [52].
Scheme 22: Controlled mono- and double methylene insertions into nitrogen–boron bonds [53].
Scheme 23: Copper-catalyzed substrate-controlled carbonylative synthesis of α-keto amides and amides [54].
Scheme 24: Divergent sulfur(VI) fluoride exchange linkage of sulfonimidoyl fluorides and alkynes [55].
Scheme 25: Modular and divergent syntheses of protoberberine and protonitidine alkaloids [56].
Recent advances in the electrochemical synthesis of organophosphorus compounds
- Babak Kaboudin,
- Milad Behroozi,
- Sepideh Sadighi and
- Fatemeh Asgharzadeh
Beilstein J. Org. Chem. 2025, 21, 770–797, doi:10.3762/bjoc.21.61
- arylphosphonates via carbon–phosphorus bond formation. In 2021, Xu et al. [52] reported an electrochemical process for synthesizing arylphosphonates through the hetero-coupling reaction of CH of arenes with a trialkyl phosphite. They have prepared 45 arene phosphonates with good to excellent yields and reported
Graphical Abstract
Scheme 1: Electrosynthesis of phenanthridine phosphine oxides.
Scheme 2: Electrosynthesis of 1-aminoalkylphosphine oxides.
Scheme 3: Various electrochemical C–P coupling reactions.
Scheme 4: Electrochemical C–P coupling reaction of indolines.
Scheme 5: Electrochemical C–P coupling reaction of ferrocene.
Scheme 6: Electrochemical C–P coupling reaction of acridines with phosphites.
Scheme 7: Electrochemical C–P coupling reaction of alkenes.
Scheme 8: Electrochemical C–P coupling reaction of arenes in a flow system.
Scheme 9: Electrochemical C–P coupling reaction of heteroarenes.
Scheme 10: Electrochemical C–P coupling reaction of thiazoles.
Scheme 11: Electrochemical C–P coupling reaction of indole derivatives.
Scheme 12: Electrosynthesis of 1-amino phosphonates.
Scheme 13: Electrochemical C–P coupling reaction of aryl and vinyl bromides.
Scheme 14: Electrochemical C–P coupling reaction of phenylpyridine with dialkyl phosphonates in the presence o...
Scheme 15: Electrochemical P–C bond formation of amides.
Scheme 16: Electrochemical synthesis of α-hydroxy phosphine oxides.
Scheme 17: Electrochemical synthesis of π-conjugated phosphonium salts.
Scheme 18: Electrochemical phosphorylation of indoles.
Scheme 19: Electrochemical synthesis of phosphorylated propargyl alcohols.
Scheme 20: Electrochemical synthesis of phosphoramidates.
Scheme 21: Electrochemical reaction of carbazole with diphenylphosphine.
Scheme 22: Electrochemical P–N coupling of carbazole with phosphine oxides.
Scheme 23: Electrochemical P–N coupling of indoles with a trialkyl phosphite.
Scheme 24: Electrochemical synthesis of iminophosphoranes.
Scheme 25: Electrochemical P–O coupling of phenols with dialkyl phosphonate.
Scheme 26: Electrochemical P–O coupling of alcohols with diphenylphosphine.
Scheme 27: Electrochemical P–S coupling of thiols with dialkylphosphines.
Scheme 28: Electrochemical thiophosphorylation of indolizines.
Scheme 29: Electrosynthesis of S-heteroaryl phosphorothioates.
Scheme 30: Electrochemical phosphorylation reactions.
Scheme 31: Electrochemical P–Se formation.
Scheme 32: Electrochemical selenation/halogenation of alkynyl phosphonates.
Scheme 33: Electrochemical enantioselective aryl C–H bond activation.
Dioxazolones as electrophilic amide sources in copper-catalyzed and -mediated transformations
- Seungmin Lee,
- Minsuk Kim,
- Hyewon Han and
- Jongwoo Son
Beilstein J. Org. Chem. 2025, 21, 200–216, doi:10.3762/bjoc.21.12
- of alkynes. Proposed catalytic cycle for the copper-catalyzed reduction of dioxazolones. Formation of isocyanates and amidated arenes from dioxazolones. Copper-catalyzed synthesis of δ-lactams via open-shell copper nitrenoid transfer. aCuBr (10 mol %) and BOX-1 (15 mol %) were used. bA stereoisomeric
Graphical Abstract
Scheme 1: Formation of isocyanates and amidated arenes from dioxazolones.
Scheme 2: Copper-catalyzed synthesis of δ-lactams via open-shell copper nitrenoid transfer. aCuBr (10 mol %) ...
Figure 1: Proposed reaction pathway for the copper-catalyzed synthesis of δ-lactams from dioxazolones.
Scheme 3: Copper(II)-catalyzed synthesis of 1,2,4-triazole derivatives.
Figure 2: Proposed reaction mechanism for the copper-catalyzed synthesis of 1,2,4-triazole analogues from dio...
Scheme 4: Copper(I)-catalyzed synthesis of N-acyl amidines from dioxazolones, acetylenes, and amines. aPerfor...
Figure 3: Proposed reaction mechanism for the copper(I)-catalyzed synthesis of N-acyl amidines.
Scheme 5: Preparation of N-arylamides from dioxazolones and boronic acids using a copper salt.
Figure 4: Proposed reaction pathway for the copper-mediated synthesis of N-arylamides from dioxazolones.
Scheme 6: Copper-catalyzed preparation of N-acyl iminophosphoranes from dioxazolones.
Figure 5: Proposed reaction pathway for the copper-catalyzed synthesis of N-acyl iminophosphoranes from dioxa...
Scheme 7: Copper-catalyzed synthesis of N-acyl sulfenamides. a1.0 equiv of 18 and 2.0 equiv of 19 were used. b...
Figure 6: Proposed reaction mechanism for the copper-catalyzed S-amidation of thiols.
Scheme 8: Copper-catalyzed asymmetric hydroamidation of vinylarenes. a4 mol % + 2 mol % catalyst was used. b4...
Figure 7: Proposed reaction mechanism for the copper-catalyzed hydroamidation of vinylarenes.
Scheme 9: Copper-catalyzed anti-Markovnikov hydroamidation of alkynes.
Figure 8: Proposed reaction mechanism for the copper-catalyzed amidation of alkynes.
Scheme 10: Copper-catalyzed preparation of primary amides through N–O bond reduction using reducing agent.
Figure 9: Proposed catalytic cycle for the copper-catalyzed reduction of dioxazolones.
Recent advances in electrochemical copper catalysis for modern organic synthesis
- Yemin Kim and
- Won Jun Jang
Beilstein J. Org. Chem. 2025, 21, 155–178, doi:10.3762/bjoc.21.9
- the product are accessible by adjusting the two distinct chiral catalysts. C–N Bond formation In 2018, Mei et al. developed the electrochemical C–H amination of arenes with amine electrophiles using copper catalysis, which provided a step-economical approach for the synthesis of aromatic amines by
Graphical Abstract
Figure 1: General mechanisms of traditional and radical-mediated cross-coupling reactions.
Figure 2: Types of electrocatalysis (using anodic oxidation).
Figure 3: Recent developments and features of electrochemical copper catalysis.
Figure 4: Scheme and proposed mechanism for Cu-catalyzed alkynylation and annulation of benzamide.
Figure 5: Scheme and proposed mechanism for Cu-catalyzed asymmetric C–H alkynylation.
Figure 6: Scheme for Cu/TEMPO-catalyzed C–H alkenylation of THIQs.
Figure 7: Scheme and proposed mechanism for Cu-catalyzed electrophotochemical enantioselective cyanation of b...
Figure 8: Scheme and proposed mechanism for Cu-catalyzed electrophotochemical asymmetric heteroarylcyanation ...
Figure 9: Scheme and proposed mechanism for Cu-catalyzed enantioselective regiodivergent cross-dehydrogenativ...
Figure 10: Scheme and proposed mechanism for Cu/Ni-catalyzed stereodivergent homocoupling of benzoxazolyl acet...
Figure 11: Scheme and proposed mechanism for Cu-catalyzed electrochemical amination.
Figure 12: Scheme and proposed mechanism for Cu-catalyzed electrochemical azidation of N-arylenamines and annu...
Figure 13: Scheme and proposed mechanism for Cu-catalyzed electrochemical halogenation.
Figure 14: Scheme and proposed mechanism for Cu-catalyzed asymmetric cyanophosphinoylation of vinylarenes.
Figure 15: Scheme and proposed mechanism for Cu/Co dual-catalyzed asymmetric hydrocyanation of alkenes.
Figure 16: Scheme and proposed mechanism for Cu-catalyzed electrochemical diazidation of olefins.
Figure 17: Scheme and proposed mechanism for Cu-catalyzed electrochemical azidocyanation of alkenes.
Figure 18: Scheme and proposed mechanism for Cu-catalyzed electrophotochemical asymmetric decarboxylative cyan...
Figure 19: Scheme and proposed mechanism for electrocatalytic Chan–Lam coupling.
Cu(OTf)2-catalyzed multicomponent reactions
- Sara Colombo,
- Camilla Loro,
- Egle M. Beccalli,
- Gianluigi Broggini and
- Marta Papis
Beilstein J. Org. Chem. 2025, 21, 122–145, doi:10.3762/bjoc.21.7
- directly to the alkene, then reacts with the nucleophile to afford product 7. The regioselective 1,2-difunctionalization of allyl alcohol has been developed as a three-component cascade reaction using arenes and sulfonamides as nucleophiles to achieve arylation/hydroamination processes. The reaction
Graphical Abstract
Figure 1: Plausible general catalytic activation for ionic or radical mechanisms.
Scheme 1: Synthesis of α-aminonitriles 1.
Scheme 2: Synthesis of β-amino ketone or β-amino ester derivatives 3.
Scheme 3: Synthesis of 1-(α-aminoalkyl)-2-naphthol derivatives 4.
Scheme 4: Synthesis of thioaminals 5.
Scheme 5: Synthesis of aryl- or amine-containing alkanes 6 and 7.
Scheme 6: Synthesis of 1-aryl-2-sulfonamidopropanes 8.
Scheme 7: Synthesis of α-substituted propargylamines 10.
Scheme 8: Synthesis of N-propargylcarbamates 11.
Scheme 9: Synthesis of (E)-vinyl sulfones 12.
Scheme 10: Synthesis of o-halo-substituted aryl chalcogenides 13.
Scheme 11: Synthesis of α-aminophosphonates 14.
Scheme 12: Synthesis of unsaturated furanones and pyranones 15–17.
Scheme 13: Synthesis of substituted dihydropyrimidines 18.
Scheme 14: Regioselective synthesis of 1,4-dihydropyridines 20.
Scheme 15: Synthesis of tetrahydropyridines 21.
Scheme 16: Synthesis of furoquinoxalines 22.
Scheme 17: Synthesis of 2,4-substituted quinolines 23.
Scheme 18: Synthesis of cyclic ether-fused tetrahydroquinolines 24.
Scheme 19: Practical route for 1,2-dihydroisoquinolines 25.
Scheme 20: Synthesis of 2,3-dihydroquinazolin-4(1H)-one derivatives 26.
Scheme 21: Synthesis of polysubstituted pyrroles 27.
Scheme 22: Enantioselective synthesis of polysubstituted pyrrolidines 30 directed by the copper complex 29.
Scheme 23: Synthesis of 4,5-dihydropyrazoles 31.
Scheme 24: Synthesis of 2 arylisoindolinones 32.
Scheme 25: Synthesis of imidazo[1,2-a]pyridines 33.
Scheme 26: Synthesis of isoxazole-linked imidazo[1,2-a]azines 35.
Scheme 27: Synthesis of 2,3-dihydro-1,2,4-triazoles 36.
Scheme 28: Synthesis of naphthopyrans 37.
Scheme 29: Synthesis of benzo[g]chromene derivatives 38.
Scheme 30: Synthesis of naphthalene annulated 2-aminothiazoles 39, piperazinyl-thiazoloquinolines 40 and thiaz...
Scheme 31: Synthesis of furo[3,4-b]pyrazolo[4,3-f]quinolinones 42.
Scheme 32: Synthesis of spiroindoline-3,4’-pyrano[3,2-b]pyran-4-ones 43.
Scheme 33: Synthesis of N-(α-alkoxy)alkyl-1,2,3-triazoles 44.
Scheme 34: Synthesis of 4-(α-tetrasubstituted)alkyl-1,2,3-triazoles 45.
Recent advances in organocatalytic atroposelective reactions
- Henrich Szabados and
- Radovan Šebesta
Beilstein J. Org. Chem. 2025, 21, 55–121, doi:10.3762/bjoc.21.6
- transformation produced either the (Ra,Sa)-isomer using pyrrolidine tetrazole catalyst C6 or the (Sa,Sa)-diastereoisomer using quaternary ammonium salt C5 (Scheme 5). Catalyst-controlled formation of twofold and higher-order stereogenicity in axially chiral arenes was discussed in this account article [15
- axially chiral pyrroles and indoles 44 are obtained (Scheme 14). Zhu and co-workers developed a method for the atroposelective formation of arenes 48 by an NHC-catalyzed formal (4 + 2) cycloaddition [34]. The triazolium pre-catalyst (R,S)-C11 was the most efficient in providing a range of biaryls in high
Graphical Abstract
Scheme 1: Formation of axially chiral styrenes 3 via iminium activation.
Scheme 2: Synthesis of axially chiral 2-arylquinolines 6.
Scheme 3: Atroposelective intramolecular (4 + 2) annulation leading to aryl-substituted indolines.
Scheme 4: Atroposelective formation of biaryl via twofold aldol condensation.
Scheme 5: Strategy towards diastereodivergent formation of axially chiral oligonaphthylenes.
Scheme 6: Atroposelective formation of chiral biaryls based on a Michael/Henry domino reaction.
Scheme 7: Organocatalytic Michael/aldol cascade followed by oxidative aromatization.
Scheme 8: Atroposelective formation of C(sp2)–C(sp3) axially chiral compounds.
Scheme 9: NHC-catalyzed synthesis of axially chiral styrenes 26.
Scheme 10: NHC-catalyzed synthesis of biaxial chiral pyranones.
Scheme 11: Formation of bridged biaryls with eight-membered lactones.
Scheme 12: The NHC-catalyzed (3 + 2) annulation of urazoles 37 and ynals 36.
Scheme 13: NHC-catalyzed synthesis of axially chiral 4‑aryl α‑carbolines 41.
Scheme 14: NHC-catalyzed construction of N–N-axially chiral pyrroles and indoles.
Scheme 15: NHC-catalyzed oxidative Michael–aldol cascade.
Scheme 16: NHC-catalyzed (4 + 2) annulation for the synthesis of benzothiophene-fused biaryls.
Scheme 17: NHC-catalyzed desymmetrization of N-aryl maleimides.
Scheme 18: NHC-catalyzed deracemization of biaryl hydroxy aldehydes 55a–k into axially chiral benzonitriles 56a...
Scheme 19: NHC-catalyzed desymmetrization of 2-aryloxyisophthalaldehydes.
Scheme 20: NHC-catalyzed DKR of 2-arylbenzaldehydes 62.
Scheme 21: Atroposelective biaryl amination.
Scheme 22: CPA-catalyzed atroposelective amination of 2-anilinonaphthalenes.
Scheme 23: Atroposelective DKR of naphthylindoles.
Scheme 24: CPA-catalyzed kinetic resolution of binaphthylamines.
Scheme 25: Atroposelective amination of aromatic amines with diazodicarboxylates.
Scheme 26: Atroposelective Friedländer heteroannulation.
Scheme 27: CPA-catalyzed formation of axially chiral 4-arylquinolines.
Scheme 28: CPA-catalyzed Friedländer reaction of arylketones with cyclohexanones.
Scheme 29: CPA-catalyzed atroposelective Povarov reaction.
Scheme 30: Atroposelective CPA-catalyzed Povarov reaction.
Scheme 31: Paal–Knorr formation of axially chiral N-pyrrolylindoles and N-pyrrolylpyrroles.
Scheme 32: Atroposelective Paal–Knorr reaction leading to N-pyrrolylpyrroles.
Scheme 33: Atroposelective Pictet–Spengler reaction of N-arylindoles with aldehydes.
Scheme 34: Atroposelective Pictet–Spengler reaction leading to tetrahydroisoquinolin-8-ylanilines.
Scheme 35: Atroposelective formation of arylindoles.
Scheme 36: CPA-catalyzed arylation of naphthoquinones with indolizines.
Scheme 37: Atroposelective reaction of o-naphthoquinones.
Scheme 38: CPA-catalyzed formation of axially chiral arylquinones.
Scheme 39: CPA-catalyzed axially chiral N-arylquinones.
Scheme 40: Atroposelective additions of bisindoles to isatin-based 3-indolylmethanols.
Scheme 41: CPA-catalyzed synthesis of axially chiral arylindolylindolinones.
Scheme 42: CPA-catalyzed reaction between bisindoles and ninhydrin-derived 3-indoylmethanols.
Scheme 43: Atroposelective reaction of bisindoles and isatin-derived imines.
Scheme 44: CPA-catalyzed formation of axially chiral bisindoles.
Scheme 45: Atroposelective reaction of 2-naphthols with alkynylhydroxyisoindolinones.
Scheme 46: CPA-catalyzed reaction of indolylnaphthols with propargylic alcohols.
Scheme 47: Atroposelective formation of indolylpyrroloindoles.
Scheme 48: Atroposelective reaction of indolylnaphthalenes with alkynylnaphthols.
Scheme 49: CPA-catalyzed addition of naphthols to alkynyl-2-naphthols and 2-naphthylamines.
Scheme 50: CPA-catalyzed formation of axially chiral aryl-alkene-indoles.
Scheme 51: CPA-catalyzed formation of axially chiral styrenes.
Scheme 52: Atroposelective formation of alkenylindoles.
Scheme 53: Atroposelective formation of axially chiral arylquinolines.
Scheme 54: Atroposelective (3 + 2) cycloaddition of alkynylindoles with azonaphthalenes.
Scheme 55: CPA-catalyzed formation of axially chiral 3-(1H-benzo[d]imidazol-2-yl)quinolines.
Scheme 56: Atroposelective cyclization of 3-(arylethynyl)-1H-indoles.
Scheme 57: Atroposelective three-component heteroannulation.
Scheme 58: CPA-catalyzed formation of arylbenzimidazols.
Scheme 59: CPA-catalyzed reaction of N-naphthylglycine esters with nitrosobenzenes.
Scheme 60: CPA-catalyzed formation of axially chiral N-arylbenzimidazoles.
Scheme 61: CPA-catalyzed formation of axially chiral arylbenzoindoles.
Scheme 62: CPA-catalyzed formation of pyrrolylnaphthalenes.
Scheme 63: CPA-catalyzed addition of naphthols and indoles to nitronaphthalenes.
Scheme 64: Atroposelective reaction of heterobiaryl aldehydes and aminobenzamides.
Scheme 65: Atroposelective cyclization forming N-arylquinolones.
Scheme 66: Atroposelective formation of 9H-carbazol-9-ylnaphthalenes and 1H-indol-1-ylnaphthalene.
Scheme 67: CPA-catalyzed formation of pyrazolylnaphthalenes.
Scheme 68: Atroposelective addition of diazodicarboxamides to azaborinephenols.
Scheme 69: Catalytic formation of axially chiral arylpyrroles.
Scheme 70: Atroposelective coupling of 1-azonaphthalenes with 2-naphthols.
Scheme 71: CPA-catalyzed formation of axially chiral oxindole-based styrenes.
Scheme 72: Atroposelective electrophilic bromination of aminonaphthoquinones.
Scheme 73: Atroposelective bromination of dienes.
Scheme 74: CPA-catalyzed formation of axially chiral 5-arylpyrimidines.
Scheme 75: Atroposelective hydrolysis of biaryloxazepines.
Scheme 76: Atroposelective opening of dinaphthosiloles.
Scheme 77: Atroposelective reduction of naphthylenals.
Scheme 78: Atroposelective allylic substitution with 2-naphthols.
Scheme 79: Atroposelective allylic alkylation with phosphinamides.
Scheme 80: Atroposelective allylic substitution with aminopyrroles.
Scheme 81: Atroposelective allylic substitution with aromatic sulfinamides.
Scheme 82: Atroposelective sulfonylation of naphthylynones.
Scheme 83: Squaramide-catalyzed reaction of alkynyl-2-naphthols with 5H-oxazolones.
Scheme 84: Formation of axially chiral styrenes via sulfonylative opening of cyclopropanols.
Scheme 85: Atroposelective organo-photocatalyzed sulfonylation of alkynyl-2-naphthols.
Scheme 86: Thiourea-catalyzed atroposelective cyclization of alkynylnaphthols.
Scheme 87: Squaramide-catalyzed formation of axially chiral naphthylisothiazoles.
Scheme 88: Atroposelective iodo-cyclization catalyzed by squaramide C69.
Scheme 89: Squaramide-catalyzed formation of axially chiral oligoarenes.
Scheme 90: Atroposelective ring-opening of cyclic N-sulfonylamides.
Scheme 91: Thiourea-catalyzed kinetic resolution of naphthylpyrroles.
Scheme 92: Atroposelective ring-opening of arylindole lactams.
Scheme 93: Atroposelective reaction of 1-naphthyl-2-tetralones and diarylphosphine oxides.
Scheme 94: Atroposelective reaction of iminoquinones with indoles.
Scheme 95: Kinetic resolution of binaphthylalcohols.
Scheme 96: DKR of hydroxynaphthylamides.
Scheme 97: Atroposelective N-alkylation with phase-transfer catalyst C75.
Scheme 98: Atroposelective allylic substitution via kinetic resolution of biarylsulfonamides.
Scheme 99: Atroposelective bromo-functionalization of alkynylarenes.
Scheme 100: Sulfenylation-induced atroposelective cyclization.
Scheme 101: Atroposelective O-sulfonylation of isochromenone-indoles.
Scheme 102: NHC-catalyzed atroposelective N-acylation of anilines.
Scheme 103: Peptide-catalyzed atroposelective ring-opening of lactones.
Scheme 104: Peptide-catalyzed coupling of 2-naphthols with quinones.
Scheme 105: Atroposelective nucleophilic aromatic substitution of fluoroarenes.
Synthesis, structure and π-expansion of tris(4,5-dehydro-2,3:6,7-dibenzotropone)
- Yongming Xiong,
- Xue Lin Ma,
- Shilong Su and
- Qian Miao
Beilstein J. Org. Chem. 2025, 21, 1–7, doi:10.3762/bjoc.21.1
- , expanding its π-skeleton through the Barton–Kellogg and Scholl reactions led to the successful synthesis of a curved polycyclic arene containing three heptagons and two pentagons. Keywords: carbon schwarzites; polycyclic arenes; Scholl reaction; seven-membered carbocycle; Yamamoto coupling; Introduction
- definitively synthesized. The three-dimensional graphene-like carbons formed in a zeolite-template are the carbon forms that are the closest to carbon schwarzites so far [6][7]. Fragments of carbon schwarzites that retain their key structural characteristics are negatively curved polycyclic arenes [8][9
- recently showed that polymerizing negatively curved polycyclic arenes produced an amorphous covalent network. This network was able to mimic the structure and function of carbon schwarzites, serving as an anode material in lithium-ion batteries with high capacity [21]. Further exploration of bottom-up
Graphical Abstract
Figure 1: Structures of compounds 1–3 and the polycyclic skeleton of 1 as mapped on a carbon schwarzite unit ...
Scheme 1: a) Synthesis of 1; b) reactions of 1; c) synthesis of 3.
Figure 2: (a) Structures of 1 in the colorless crystal; (b) structures of (P,M,P)-1 in the yellow crystal. (C...
Figure 3: Structure of (M,P,M)-3 in the crystal of 3·CH2Cl2 (carbon and oxygen atoms are shown as grey and re...
Figure 4: UV–vis absorption spectrum (black line) and emission spectrum (blue line, excited at 400 nm) of com...
