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Search for "C-" in Full Text gives 3862 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Salen–scandium(III) complex-catalyzed asymmetric (3 + 2) annulation of aziridines and aldehydes

  • Linqiang Wang and
  • Jiaxi Xu

Beilstein J. Org. Chem. 2025, 21, 1087–1094, doi:10.3762/bjoc.21.86

Graphical Abstract
  • derivatives were obtained under asymmetric catalysis with a Ni(II)–bisoxazoline complex [15] and a Nd(OTf)3/N,N'-dioxide/LiNTf2 delay catalytic system [16], respectively (Scheme 1b and c). However, further exploration for convenient asymmetric catalytic synthetic methods is still in demand because the former
  • The reaction of diethyl 3-phenyl-1-(4-toluenesulfonyl)aziridine-2,2-dicarboxylate (1a) and benzaldehyde (2a) was first selected as a model reaction to optimize the reaction conditions (Table 1). When aziridine 1a (0.2 mmol) and aldehyde 2a (0.3 mmol) in dried toluene (1 mL) were stirred at 10 °C for
  • time. The yield was improved from 21% to 29% to 34% with similar enantio- and diastereoselectivities at 25 °C, 45 °C, and 55 °C, respectively, but the enantioselectivity decreased slightly at 55 °C (Table 1, entries 15–17). Further extending the reaction time to 48 h at 55 °C, resulted in an increased
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Published 28 May 2025

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
  • cinnamic acid. For example, Chen and co-workers (2020) reported the Pd-catalyzed N-acylation of cinnamic acids using tertiary amines to generate the corresponding amides 83 and 84 in good yields via C–N cleavage (Scheme 25) [61]. The active Pd0 species was inserted into the carboxylate group to afford the
  • yield. The reaction proceeds via a CeO2-coordinated carboxylate mode (Scheme 31A) [67]. In addition, the catalyst also offered high reusability for up to 4 runs thus further promoting the eco-friendliness. Carbonyl activation via Lewis acid–O=C interaction has also been achieved using other transition
  • cinnamic acid (7) to give amide 12 in excellent yield via Ti(IV)–O=C complex 102 (Scheme 31C) [69]. 2.1.3 Photocatalysis: Photoredox catalysis has gained much attention as a sustainable alternative approach to performing O/N-acylation by utilizing light as a renewable source. For example, Li and co-workers
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Published 28 May 2025

Biobased carbon dots as photoreductants – an investigation by using triarylsulfonium salts

  • Valentina Benazzi,
  • Arianna Bini,
  • Ilaria Bertuol,
  • Mariangela Novello,
  • Federica Baldi,
  • Matteo Hoch,
  • Alvise Perosa and
  • Stefano Protti

Beilstein J. Org. Chem. 2025, 21, 1024–1030, doi:10.3762/bjoc.21.84

Graphical Abstract
  • carbon nanomaterials category in view of their stability, water affinity/dispersibility, and low toxicity [1][2][3][4]. Such nanomaterials significantly absorb in the 280–350 nm region due to a wide range of π–π* (C=C) and n–π* (C=O) transitions in both the core and on the surface of the particles. CDs
  • photooxidant or photoreductant in the presence of a suitable electron donor or acceptor [18], and these properties have been exploited in procedures for the formation of both CC and C–heteroatom bonds [18][19]. Our research groups recently focused on the application of CDs in light-mediated organic synthesis
  • from direct photoreactivity [24][25], sulfonium salts can be easily reduced under photoredox-catalyzed conditions [20][21][22], and the resulting radical undergoes homolytic cleavage of one of the C–S bonds, releasing an aryl radical Ar• and a diaryl sulfide Ar2S. Subsequently, triarylsulfonium ions
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Published 26 May 2025

Pd-Catalyzed asymmetric allylic amination with isatin using a P,olefin-type chiral ligand with C–N bond axial chirality

  • Natsume Akimoto,
  • Kaho Takaya,
  • Yoshio Kasashima,
  • Kohei Watanabe,
  • Yasushi Yoshida and
  • Takashi Mino

Beilstein J. Org. Chem. 2025, 21, 1018–1023, doi:10.3762/bjoc.21.83

Graphical Abstract
  • ligands with axial chirality for Pd-catalyzed asymmetric allylic substitution reactions. For example, the Zhou group reported a P,olefin-type chiral ligand 3 with CC bond axial chirality for this reaction (Figure 2) [27]. Additionally, we have recently reported chiral ligands with C–N bond axial
  • detector and found that the C(aryl)–N(amide) bond axial chirality exists in amide compound 7. We attempted the optical resolution of racemic compound (±)-7 and obtained (+)-7 and (−)-7 using a semi-preparative chiral HPLC on 50 milligram scales. We also investigated the racemization process associated with
  • the axial chirality of compound 7 (see Supporting Information File 1). The racemization barrier (ΔG‡rac) of (−)-7 in n-dodecane was determined to be 25.0 kcal/mol at 25 °C, as calculated using the Arrhenius and Eyring equations [33][34][35]. Therefore, the half-life of racemization of ligand (−)-7 at
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Published 23 May 2025

Synthesis of pyrrolo[3,2-d]pyrimidine-2,4(3H)-diones by domino C–N coupling/hydroamination reactions

  • Ruben Manuel Figueira de Abreu,
  • Robin Tiedemann,
  • Peter Ehlers and
  • Peter Langer

Beilstein J. Org. Chem. 2025, 21, 1010–1017, doi:10.3762/bjoc.21.82

Graphical Abstract
  • Abstract A variety of pyrrolo[3,2-d]pyrimidine-2,4(3H)-diones were prepared by a combination of Sonogashira reaction and subsequent cyclization by domino C–N coupling/hydroamination reaction. The optical properties (UV–vis absorption and fluorescence) depend on the substitution pattern of the compounds
  • instance, deazapurines represent heterocyclic fused pyrimidine bases which have found special attention, due to their widespread occurrence in natural alkaloids exhibiting various biological properties. For example, cadeguomycin (A), tubercidin (B), and toyocamycin (C) show antibiotic properties, while
  • obtained for product 3e derived from 3-tolylacetylene. However, the yield for compound 3f dropped to 60% because of the more sterically hindered 2-tolylacetylene. The domino C–N cross-coupling/hydroamination reaction of 3a–h with various anilines was studied next (Scheme 2) [28][29]. The conditions were
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Published 22 May 2025

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

Graphical Abstract
  • aldol condensation of 5 provided the tetracyclic α,β-unsaturated enone 6 in 57% yield. Subsequent catalytic hydrogenation using Pd/C conditions delivered the hydrogen to the alkene from the less hindered face, producing ketone 7 with high diastereoselectivity. Final reduction of both the amide and
  • the reduction of amide-generated ketone 12 after a subsequent Dess–Martin oxidation. Upon treatment of 12 with Co(acac)2 and PhSiH3 in iPrOH at 80 °C, the Mukaiyama hydration of enamide delivered hemiaminal 13. Despite the incorrect configuration of the newly formed hydroxy group, it is considered
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Published 22 May 2025

On the photoluminescence in triarylmethyl-centered mono-, di-, and multiradicals

  • Daniel Straub,
  • Markus Gross,
  • Mona E. Arnold,
  • Julia Zolg and
  • Alexander J. C. Kuehne

Beilstein J. Org. Chem. 2025, 21, 964–998, doi:10.3762/bjoc.21.80

Graphical Abstract
  • Daniel Straub Markus Gross Mona E. Arnold Julia Zolg Alexander J. C. Kuehne OC III - Institute of Organic and Macromolecular Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany Center for Integrated Quantum Science and Technology, Ulm University, Albert-Einstein-Allee 11, 89081
  • –LUMO energy gaps are identical and their respective transitions exhibit identical transition dipole moments [19][32][33]. For the |D1⟩ transition these two degenerate transitions mix in an out-of-phase fashion leading to the observed weak absorption at 544 nm (see Figure 1b and c). When looking at the
  • Mulliken symmetry labels, one realizes that the |D1⟩ transition is in fact symmetry forbidden. By contrast, in-phase mixing of the transitions for the |D2⟩ transition leads to strong absorption at 374 nm, a transition that is symmetry allowed (see Figure 1b and c). In TTM, the ϕ is independent of the
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Published 21 May 2025

Studies on the syntheses of β-carboline alkaloids brevicarine and brevicolline

  • Benedek Batizi,
  • Patrik Pollák,
  • András Dancsó,
  • Péter Keglevich,
  • Gyula Simig,
  • Balázs Volk and
  • Mátyás Milen

Beilstein J. Org. Chem. 2025, 21, 955–963, doi:10.3762/bjoc.21.79

Graphical Abstract
  • , versatile key triflate intermediate 3, which allowed the introduction of substituents attached by a CC bond to position 4 of the β-carboline scaffold by cross-coupling reactions. Sonogashira reaction of compound 3 with N-(3-butynyl)phthalimide (4) led to coupled compound 5. Cleavage of the phthalimide
  • hydrogenation of the C=C double bond in the side chain gave brevicarine (2). The first total synthesis of brevicarine is shown in Scheme 3 [2][20][21]. Condensation of indole (11) with 1-methylpiperidone (12) gave compound 13 [22]. N-Alkylation of 13 with benzyl bromide, followed by treatment of the quaternary
  • 21 under extremely harsh conditions (100 °C, 130 bar), followed by N-acetylation gave a mixture of diastereomeric racemates 22, which was cyclized to a diastereomeric mixture of β-carboline derivatives 23. Heating of 23 in pivalic acid in the presence of a catalytic amount of trifluoroacetic acid
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Published 20 May 2025

Harnessing tethered nitreniums for diastereoselective amino-sulfonoxylation of alkenes

  • Shyam Sathyamoorthi,
  • Appasaheb K. Nirpal,
  • Dnyaneshwar A. Gorve and
  • Steven P. Kelley

Beilstein J. Org. Chem. 2025, 21, 947–954, doi:10.3762/bjoc.21.78

Graphical Abstract
  • equivalent of commercial iodomesitylene diacetate (CAS [33035-41-5]) and 1 equivalent of MsOH (Table 1, entry 4). Here, it was necessary to maintain a temperature of 0 °C, as vigorous bubbling and rapid decomposition occurred when the reaction was initiated at room temperature. In all cases (Table 1), only a
  • steric bulk of the isopropyl group unfavorably affected the reaction outcome. However, we found that when 3 was subjected to the more active combination of iodomesitylene diacetate and p-TsOH·H2O at 0 °C in CH2Cl2, the desired product 4 formed in a much-improved yield of 57%. Not all tethers were
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Published 19 May 2025

Study of tribenzo[b,d,f]azepine as donor in D–A photocatalysts

  • Katy Medrano-Uribe,
  • Jorge Humbrías-Martín and
  • Luca Dell’Amico

Beilstein J. Org. Chem. 2025, 21, 935–944, doi:10.3762/bjoc.21.76

Graphical Abstract
  • offers unique features, including twisted structures, reduced π–π stacking, and enhanced reverse intersystem crossing rates, becoming a better donor compared to fully planar compounds as carbazole (c). Similarly, 5H-dibenz[b,f]azepine (IMD, b) has been incorporated into D–A–D structures, showing
  • interesting photophysical properties compared to common substrates like c, diphenylamine (d), and phenoxazine (e) [28][29][30]. However, their potential as D-unit in organic PCs remains unexplored. For this reason, studying this avenue could unlock new opportunities for the synthesis and design of more
  • . Additionally, we aim to evaluate the unique effect of the TBA donor unit (a) compared to other donors. We next synthesized diverse D–A structures employing common nitrogen-based compounds widely used in materials chemistry like carbazole (c), diphenylamine (d), and phenoxazine (e). Furthermore, we wanted to
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Published 14 May 2025

A convergent synthetic approach to the tetracyclic core framework of khayanolide-type limonoids

  • Zhiyang Zhang,
  • Jialei Hu,
  • Hanfeng Ding,
  • Li Zhang and
  • Peirong Rao

Beilstein J. Org. Chem. 2025, 21, 926–934, doi:10.3762/bjoc.21.75

Graphical Abstract
  • involving limonoids. Krishnolides A and C (7 and 8, respectively; Scheme 1A) were identified by Wu and co-workers from the seeds of a Krishna mangrove Xylocarpus moluccensis [26]. These two molecules belong to khayanolides, a class of rearranged phragmalin limonoids characterized by a structurally intricate
  • tricyclo[4.2.110,30.11,4]decane ring system. Additionally, krishnolides A and C contain 9–11 stereogenic centers and exhibit diverse oxidation patterns. Their relative and absolute configurations were determined through NMR, HRESIMS and ECD experiments, as well as single crystal X-ray diffraction analysis
  • convergent approach leveraging an AcOH-interrupted Nazarov cyclization to establish the [5,5,6,6]-tetracyclic scaffold with precise stereochemical fidelity. Results and Discussion Our retrosynthetic analysis toward krishnolides A (7) and C (8) is delineated in Scheme 1B. We hypothesized that these two
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Published 12 May 2025

Silver(I) triflate-catalyzed post-Ugi synthesis of pyrazolodiazepines

  • Muhammad Hasan,
  • Anatoly A. Peshkov,
  • Syed Anis Ali Shah,
  • Andrey Belyaev,
  • Chang-Keun Lim,
  • Shunyi Wang and
  • Vsevolod A. Peshkov

Beilstein J. Org. Chem. 2025, 21, 915–925, doi:10.3762/bjoc.21.74

Graphical Abstract
  • , propiolic acids 8a–d, and isocyanides 4a–e. By conducting the reactions in methanol at 70 °C, we obtained the desired Ugi adducts 15a–x in fair to good yields of 26–72% allowing for the variation of substituents across all components of the U4CR (Scheme 2). Notably, the Ugi reaction toward substrate 15a
  • , when performed at room temperature, proceeded with lower efficiency compared to the reaction at 70 °C, leaving some of the starting 1H-pyrazole-3-carbaldehyde (14a) unreacted. Propargylamide 15a was selected as a model substrate to optimize the reaction conditions for the intramolecular
  • by nitrogen nucleophiles [59][60]. When the reaction was conducted with 5 mol % of AgOTf in toluene at 80 °C for 20 hours, pyrazolo[1,5-a][1,4]diazepine 16a was obtained in 46% yield, while complete conversion of the starting material 15a was not achieved (Table 1, entry 1). Increasing the
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Published 08 May 2025

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

Graphical Abstract
  • , oxidative addition of the C–I bond to palladium formed the four-membered aryl–palladium complex Int-5. Steric hindrance from the bulky dppm ligand, combined with slower aryne release (using KF as the fluoride source), attenuated aryne coordination. Under these electron-deficient conditions, CO
  • ensuring high regioselectivity. In 2018, the Jiang group developed a regiodivergent synthetic method for indolo[3,2-c]coumarins 10 and benzofuro[3,2-c]quinolinones 9 via controllable palladium(II)-catalyzed carbonylative cyclization (Scheme 3) [21]. When ligand L3 coordinates with the palladium center, the
  • elimination yields the benzofuro[3,2-c]quinolinone product 9 along with a Pd(0) species, which is reoxidized to Pd(II) by BQ (benzoquinone). When the ligand is switched to the sterically bulky and electron-rich dppm, the chemoselectivity is reversed: the palladium center now preferentially coordinates with
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Published 07 May 2025

Dicarboxylate recognition based on ultracycle hosts through cooperative hydrogen bonding and anion–π interactions

  • Wen-Hui Mi,
  • Teng-Yu Huang,
  • Xu-Dong Wang,
  • Yu-Fei Ao,
  • Qi-Qiang Wang and
  • De-Xian Wang

Beilstein J. Org. Chem. 2025, 21, 884–889, doi:10.3762/bjoc.21.72

Graphical Abstract
  • reorganization likely involves the cleavage and re-formation of the dynamic Ctriazine–OAr bonds, and the presence of an excess of base could facilitate the formation of the thermodynamic-favored reorganized products [29][31]. The benzyl groups were subsequently removed under Pd/C and H2 conditions to afford the
  • ) solution of the compound at 4 °C, enabling structural analysis of the ultracycle. As illustrated in Figure 1, the backbone of B4aH adopts a Z-like shape with a flexible conformation. The two oxacalix[2]arene[2]triazine subcavities are positioned along the short axis in a staggered face-to-face arrangement
  • , while the glycol chains are oriented along the long axis in the opposite orientations. In packing mode, the submacrocycle units form close contacts through intermolecular hydrogen bonding, C–H···π, and lone pair–π interactions, resulting in a 1D linear assembly. Anion recognition With the functional
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Published 06 May 2025

Cu–Bpin-mediated dimerization of 4,4-dichloro-2-butenoic acid derivatives enables the synthesis of densely functionalized cyclopropanes

  • Patricia Gómez-Roibás,
  • Andrea Chaves-Pouso and
  • Martín Fañanás-Mastral

Beilstein J. Org. Chem. 2025, 21, 877–883, doi:10.3762/bjoc.21.71

Graphical Abstract
  • species A which is in equilibrium with the Cu–O enolate B [11]. In the presence of excess of LiOt-Bu, a salt metathesis reaction between this base and intermediate B generates lithium enolate C and LCuOt-Bu to close the copper catalytic cycle. The formation of a lithium enolate is consistent with the
  • different diastereoselectivity observed when other bases featuring different metal cations were used (Table 1, entry 2 vs entry 5), and the absence of any significant stereochemical influence from the copper complex (Table 1, entries 9–14). Lithium enolate C would then undergo a diastereoselective conjugate
  • details). In contrast, the use of CsF in dioxane at 70 °C proved to be efficient and selectively provided cyclopropane 9 in good yield, albeit with no diastereoselectivity (Table 2, entry 1). Cs2CO3 was also selective for this cyclization and provided a slight increase in diastereoselectivity, although
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Published 05 May 2025

Light-enabled intramolecular [2 + 2] cycloaddition via photoactivation of simple alkenylboronic esters

  • Lewis McGhie,
  • Hannah M. Kortman,
  • Jenna Rumpf,
  • Peter H. Seeberger and
  • John J. Molloy

Beilstein J. Org. Chem. 2025, 21, 854–863, doi:10.3762/bjoc.21.69

Graphical Abstract
  • considering recent advances enabling subsequent intramolecular H-atom abstraction [51] and efficient rearrangements [73][74]. A) Energy transfer catalysis of alkenes in organic synthesis. B) Energy transfer catalysis of conjugated borylated alkenes. C) Energy transfer catalysis of simple alkenylboronic esters
  • cyclobutyldiol. A) Product derivatization and B) transition-metal EnT catalysis. Reaction conditions A): 4d (1 equiv), H2O2 (30 wt % in H2O), aq NaH2PO4, THF, 0 °C; B) 4 (1 equiv), KF (4 equiv), ʟ-tartaric acid (2.1 equiv), MeOH, MeCN, H2O, rt. Probing EnT catalysis of alkenylboronic ester 1a via alkene
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Published 30 Apr 2025

Unraveling cooperative interactions between complexed ions in dual-host strategy for cesium salt separation

  • Zhihua Liu,
  • Ya-Zhi Chen,
  • Ji Wang,
  • Qingling Nie,
  • Wei Zhao and
  • Biao Wu

Beilstein J. Org. Chem. 2025, 21, 845–853, doi:10.3762/bjoc.21.68

Graphical Abstract
  • carbonyl (C=O) groups, as well as direct ion-pairing interactions between 18-crown-6-complexed Cs+ and hexaurea-bound PO43−. Single-crystal structural analysis corroborates these interactions, shedding light on the underlying mechanisms and providing valuable guidance for the rational design of advanced
  • , only two examples provide clear evidence of cooperative interactions based on single crystal structures [28][29], where the 18-crown-6 complexed K+ cation forms ion-dipole interactions with the carbonyl (C=O) or nitro (NO2) groups of the anion-bound receptors (KF and K2CO3). Recently, we demonstrated
  • interactions between K+ and C=O moieties [31], similar to these seen in the single crystal structures of KF and K2CO3 complexes. These provide a promising opportunity that can be used to identify the cooperative interaction underpinning complexed ions in dual-host strategy-based extraction. To do this, the
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Published 29 Apr 2025

Chitosan-supported CuI-catalyzed cascade reaction of 2-halobenzoic acids and amidines for the synthesis of quinazolinones

  • Xuhong Zhao,
  • Weishuang Li,
  • Mengli Yang,
  • Bojie Li,
  • Yaoyao Zhang,
  • Lizhen Huang and
  • Lei Zhu

Beilstein J. Org. Chem. 2025, 21, 839–844, doi:10.3762/bjoc.21.67

Graphical Abstract
  • (acac)2) and chitosan-supported on CuSO4 (CS@CuSO4) were explored, and the results showed that CS@CuI was the most effective catalyst (Table 1, entries 7−11, 65−89% yields). To further enhance the reaction yield, the reaction temperature was increased to 90 °C, and the target product 3a was obtained in
  • -halobenzoic acids and amidines for the synthesis of quinazolinones. Substrate scope. Reaction conditions: 1 (0.5 mmol, 1.0 equiv), amidines hydrochloride 2 (0.75 mmol, 1.5 equiv), CS@CuI (10.0 mg, ICP: 14.6%, 5.0 mol %), Na2CO3 (1.25 mmol, 2.5 equiv), iPrOH/H2O 9:1 (2.0 mL), 90 °C, 12 h, argon atmosphere; a1
  • (0.2 mmol), amidine hydrochloride 2 (0.3 mmol, 1.5 equiv), CS@CuI (5.0 mol %), Na2CO3 (1.25 mmol, 2.5 equiv), iPrOH/H2O 9:1 (2.0 mL), 90 °C, 12 h, argon atmosphere. Proposed mechanism for the CS@CuI-catalyzed synthesis of quinazolinones. Scaling-up experiment (a) and recyclability of CS@CuI (b
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Published 28 Apr 2025

Substituent effects in N-acetylated phenylazopyrazole photoswitches

  • Radek Tovtik,
  • Dennis Marzin,
  • Pia Weigel,
  • Stefano Crespi and
  • Nadja A. Simeth

Beilstein J. Org. Chem. 2025, 21, 830–838, doi:10.3762/bjoc.21.66

Graphical Abstract
  • . Acylation of the pyrazole moiety led to an enhanced metastable half-life compared to the NH-PAPs. For NAc-PAP-H, we observed increased half-lifes (21.5 days, 30 °C), compared to the reported NH-PAP-H (0.066 days; 25 °C [51]) or NMe-PAP-H (10 days; 25 °C [31], all in CH3CN). In the presence of OH as
  • -PAP-CN upon 365 nm irradiation (12.5 µM in CH3CN, at 25 °C). B) Absorbance of the same sample at 365 nm (Ar, 365nm) after reaching PSS365 or PSS455, respectively, to show the recyclability. Hammett plot of NAc-PAP derivatives. Eyring plots for NAc-PAP-CN and NAc-PAP-OMe. Reaction pathway for
  • synthesizing NH-substituted, methylated-, and acetylated arylazopyrazoles. Conditions: A) NaNO2, AcOH + HCl at 0 °C, then, 2,4-pentanedione, NaOAc in EtOH + H2O, reflux; B) MeNHNH2, EtOH, reflux; C) NH2NH2, EtOH, reflux; D) AcCl, NaOAc in DCM, 0 °C to rt. Photophysical properties of synthesized PAP derivatives
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Published 25 Apr 2025

4-(1-Methylamino)ethylidene-1,5-disubstituted pyrrolidine-2,3-diones: synthesis, anti-inflammatory effect and in silico approaches

  • Nguyen Tran Nguyen,
  • Vo Viet Dai,
  • Luc Van Meervelt,
  • Do Thi Thao and
  • Nguyen Minh Thong

Beilstein J. Org. Chem. 2025, 21, 817–829, doi:10.3762/bjoc.21.65

Graphical Abstract
  • , we report the synthesis of 4-(1-methylamino)ethylidene-1,5-disubstituted pyrrolidine-2,3-diones via a reversible transimination reaction between Schiff’ base (C=N) linkage-containing pyrrolidine-2,3-dione derivatives and methylamine with yields of 80 to 92%. In addition to nuclear magnetic resonance
  • -hybridized carbon atom directly bonded to the nitrogen atom of the secondary amino group of compound 5a. In the structure of each pyrrolidine-2,3-dione derivative 3a–e, there is an α,β-unsaturated ketone moiety in which the π systems of the C=C and C=O bonds could overlap each other to yield an extended
  • and charge separation. In the resonance forms 3a’–e’, the 4-methoxybenzylamino group is covalently attached to the 4-position of the 1,5-disubstituted pyrrolidine-2,3-dione core via a Schiff’ base (C=N) linkage in which the positive charge could be delocalized on both carbon and nitrogen atoms. In
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Published 24 Apr 2025

Synthesis and photoinduced switching properties of C7-heteroatom containing push–pull norbornadiene derivatives

  • Daniel Krappmann and
  • Andreas Hirsch

Beilstein J. Org. Chem. 2025, 21, 807–816, doi:10.3762/bjoc.21.64

Graphical Abstract
  • . Starting with 1-((bromoethynyl)sulfonyl)-4-methylbenzene, which was previously prepared and characterized [40][41], Diels–Alder reaction with either cyclopentadiene, furan or Boc-protected pyrrol, resulted in the NBD precursors C-NBD1, O-NBD1 and N-NBD1, respectively [31][42]. With these precursors in hand
  • a subsequent Suzuki cross-coupling reaction with (4-(diphenylamino)phenyl)boronic acid was performed. The reaction conditions were adapted from prior experiments with C-NBD1 [40] and further refined for the heterocyclic analogues. Optimal results were achieved using K2CO3, Pd(OAc)2 and RuPhos with
  • the corresponding boronic acid in a degassed toluene/H2O mixture (4:1, v/v) which was heated to 80 °C for 18 h (for detailed information see Supporting Information File 1). Using the described procedure, the oxygen containing derivatives O-NBD2 and nitrogen substituted N-NBD2 were successfully
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Published 22 Apr 2025

Regioselective formal hydrocyanation of allenes: synthesis of β,γ-unsaturated nitriles with α-all-carbon quaternary centers

  • Seeun Lim,
  • Teresa Kim and
  • Yunmi Lee

Beilstein J. Org. Chem. 2025, 21, 800–806, doi:10.3762/bjoc.21.63

Graphical Abstract
  • bonds is one of the most efficient and atom-economical approaches for synthesizing alkyl nitriles [15][16]. Among the potential substrates, allenes have attracted significant attention because of their unique structural features, which consist of two orthogonal and contiguous C=C bonds. This dual π
  • efficiently constructed α-all-carbon quaternary centers on β,γ-unsaturated nitriles with excellent >98% regioselectivity and >98% (E)-selectivity. 1,1-Disubstituted allenes bearing silyl ether- and benzyl ether-tethered propyl groups were successfully converted into the desired nitriles 3a–c in yields ranging
  • quaternary and tertiary carbon centers. The scope of monosubstituted allenes is illustrated in Scheme 4. Allenes 4a–c substituted with alkyl groups, including phenethyl, decyl, and cyclohexyl groups, smoothly underwent hydrocyanation, yielding the corresponding nitriles 5a–c in 79–90% yield with excellent
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Published 17 Apr 2025

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

Graphical Abstract
  • electrosynthesis as a green, precise, and low-cost method to prepare phosphorous structures. Keywords: electrosynthesis; green synthesis; organophosphorus compounds; P–C bond formation; P–heteroatom bond formation; Introduction The electrochemical synthesis is a valuable and beneficial method for the preparation
  • electrode with the reaction solution. The oxidation–reduction process complements each other, and the surface of the electrode in the reaction is critical. The material of the electrode is essential [44]. Various electrodes, including carbon (C), platinum (Pt), nickel (Ni), and reticulated vitreous carbon
  • (RVC), are extensively used in the electrosynthesis of organophosphorus compounds (Table 1). Carbon (C) electrode: The carbon electrode is one of the most widely used electrodes in electrochemical synthesis. This electrode is a porous material that allows chemicals to penetrate it. On the other hand
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Review
Published 16 Apr 2025

Development and mechanistic studies of calcium–BINOL phosphate-catalyzed hydrocyanation of hydrazones

  • Carola Tortora,
  • Christian A. Fischer,
  • Sascha Kohlbauer,
  • Alexandru Zamfir,
  • Gerd M. Ballmann,
  • Jürgen Pahl,
  • Sjoerd Harder and
  • Svetlana B. Tsogoeva

Beilstein J. Org. Chem. 2025, 21, 755–765, doi:10.3762/bjoc.21.59

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  • our previous work [45], we carried out the enantioselective hydrocyanation of hydrazones using Ca–BINOL phosphate complex 6 at −10 °C in DCM for 72 h. In addition to those reaction conditions, we initially used t-BuOH as an additive [45]. The Ca–BINOL phosphate complex 6 was prepared in situ by
  • moiety are non-linear with a Ca–N–C angle of 100°. Due to the stereospecificity of the reaction, racemization would have to occur already in 9 through a topomerization (e.g., similar to a Berry pseudorotation) of the metal complex, considering that species with a quaternary carbon, as they appear in
  • isomer, with a more acute Ca–N–C angle of 92°, has greater resemblance to a (here absent) side-on form (found to dominate computationally for Ca(CN)2 in the gas phase) [54]. Fortunately, that isomer in which the isonitrile carbon is closer to the imine carbon (i.e., the hydrocyanation reaction center
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Full Research Paper
Published 14 Apr 2025

Copper-catalyzed domino cyclization of anilines and cyclobutanone oxime: a scalable and versatile route to spirotetrahydroquinoline derivatives

  • Qingqing Jiang,
  • Xinyi Lei,
  • Pan Gao and
  • Yu Yuan

Beilstein J. Org. Chem. 2025, 21, 749–754, doi:10.3762/bjoc.21.58

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  • ) trifluoroacetate (Cu(TFA)2) as the catalyst (20 mol %) under ambient air at 80 °C for 12 hours; the product 3aa was isolated by chromatographic purification (Table 1, entry 1). The use of other solvents, including acetonitrile (MeCN), tetrahydrofuran (THF), toluene, acetone and methanol (MeOH), resulted in
  • moderate yield (Table 1, entry 6). Conducting the reaction at room temperature (rt) instead of the optimal elevated temperature resulted in a lower yield (Table 1, entry 7). Increasing the reaction temperature to 100 °C did not improve the yield (Table 1, entry 8). Having established the optimal reaction
  • spirotetrahydroquinoline (STHQ) scaffolds. Substrate scope. General reaction conditions: aniline 1 (0.2 mmol), 2 (0.4 mmol), and Cu(TFA)2 (0.04 mmol) in hexane (2.0 mmol) under air atmosphere, 12 h, 80 °C. Yields refer to isolated yields. Scale-up reaction.a Proposed mechanism. Optimization of reaction conditions.a
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Letter
Published 09 Apr 2025
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