Search for "organic synthesis" in Full Text gives 781 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81
Graphical Abstract
Figure 1: Oxidative and reductive activations of organic compounds harvesting photoredox catalysis.
Figure 2: General catalytic cycles of radical ion conPET (left) and radical ion e-PRC (right).
Figure 3: “Beginner’s guide”: comparison between advantages, capacities, and prospectives of conPET and PEC.
Figure 4: A) conPET reductive dehalogenation of aryl halides with PDI. B) Reductive C–H arylation with pyrrol...
Figure 5: A) Chromoselective mono- and disubstitution or polybrominated pyrimidines with pyrroles. B) Sequent...
Figure 6: A) Synthesis of pyrrolo[1,2-a]quinolines. B) Synthesis of ullazines.
Figure 7: A) Reductive phosphorylation of aryl halides via conPET. B) Selected examples from the substrate sc...
Figure 8: A) Reductive dehalogenation of aryl halides via conPET and selected examples from the substrate sco...
Figure 9: A) Reductive C–H arylation of aryl halides via conPET (top) and selected examples from the substrat...
Figure 10: A) Reductive hydrodehalogenation of aryl halides with Mes-Acr-BF4. B) Selected examples from the su...
Figure 11: A) Reductive hydrodechlorination of aryl chlorides with 4-DPAIPN. B) Proposed formation of CO2•−. C...
Figure 12: A) Reductive conPET borylation with 3CzEPAIPN (top) and selected examples from the substrate scope ...
Figure 13: Scale-up of conPET phosphorylation with 3CzEPAIPN.
Figure 14: A) Borylation of 1d. B) Characteristics and structure of PC1 with green and red parts showing the l...
Figure 15: A) Reductive C–H arylation scope with polysulfide conPET (top) and selected examples from the subst...
Figure 16: Scale-up of A) C–H arylation and B) dehaloborylation with polysulfide photocatalysis in continuous-...
Figure 17: A) Formation of [Ir1]0 and [Ir2]0 upon PET between [Ir1]+ and Et3N. B) Mechanism of multi-photon ta...
Figure 18: A) Reductive hydrodehalogenation of aryl halides via multi-photon tandem photocatalysis. B) Selecte...
Figure 19: A) Carbonylative amidation of aryl halides in continuous flow. B) Selected examples from the substr...
Figure 20: A) General scheme for reductive (RQ) and oxidative quenching (OQ) protocols using [FeIII(btz)3](PF6)...
Figure 21: A) Carbonylative amidation of alkyl iodides with [IrIII(ppy)2(dtbbpy)]PF6. B) Selected examples fro...
Figure 22: A) Carboxylative C–N bond cleavage in cyclic amines. B) Selected examples from the substrate scope....
Figure 23: A) Formal reduction of alkenes to alkanes via transfer hydrogenation. B) Selected examples from the...
Figure 24: A) Birch-type reduction of benzenes with PMP-BPI. B) Selected examples from the substrate scope (sc...
Figure 25: Proposed mechanism of the OH− mediated conPET Birch-type reduction of benzene via generation of sol...
Figure 26: Reductive detosylation of N-tosylated amides with Mes-Acr-BF4. B) Selected examples from the substr...
Figure 27: A) Reductive detosylation of N-tosyl amides by dual PRC. B) Selected examples from the substrate sc...
Figure 28: A) Mechanism of the dual PRC based on PET between [Cu(dap)2]+ and DCA. B) Mechanism of the dual PRC...
Figure 29: A) N–O bond cleavage in Weinreb amides with anthracene. B) N–O bond cleavage in Weinreb amides rely...
Figure 30: A) Pentafluorosulfanylation and fluoride elimination. B) Mechanism of the pentafluorosulfanylation ...
Figure 31: A) α-Alkoxypentafluorosulfanylation (top) and selected examples from the substrate scope (bottom). ...
Figure 32: A) Oxidative amination of arenes with azoles catalyzed by N-Ph PTZ. B) Selected examples from the s...
Figure 33: A) C(sp3)–H bond activation by HAT via chloride oxidation by *N-Ph PTZ•+. B) Proposed mechanism for...
Figure 34: A) Recycling e-PRC C–H azolation of electron-rich arenes with pyrazoles using Mes-Acr+ as a photoca...
Figure 35: A) Radical ion e-PRC direct oxidation of unactivated arenes using TAC+ as an electro-activated phot...
Figure 36: A) Radical ion e-PRC direct oxidation of unactivated arenes using TPA as an electro-activated photo...
Figure 37: Proposed mechanism (top) and mode of preassembly (bottom).
Figure 38: A) Possible preassemblies of reactive (left) vs unreactive (right) arenes. B) Calculated spin densi...
Figure 39: A) Recycling e-PRC C(sp2 )–H acetoxylation of arenes using DDQ as a photocatalyst. B) Proposed cata...
Figure 40: Gram scale hydroxylation of benzene in a recirculated flow setup.
Figure 41: A) Radical ion e-PRC vicinal diamination of alkylarenes using TAC+ as an electro-activated photocat...
Figure 42: A) Sequential oxygenation of multiple adjacent C–H bonds under radical ion e-PRC using TAC+ as an e...
Figure 43: A) Enantioselective recycling e-PRC cyanation of benzylic C–H bonds using ADQS as photocatalyst. B)...
Figure 44: Proposed tandem mechanism by Xu and co-workers.
Figure 45: A) Enantioselective recycling e-PRC decarboxylative cyanation using Cu(acac)2, Ce(OTf)3 and a box l...
Figure 46: A) Enantioselective recycling e-PRC benzylic cyanation using Cu(MeCN)4BF4, box ligand and anthraqui...
Figure 47: A) Radical ion e-PRC acetoxyhydroxylation of aryl olefins using TAC+ as an electro-activated photoc...
Figure 48: Selected examples from the substrate scope.
Figure 49: Photoelectrochemical acetoxyhydroxylation in a recirculated flow setup.
Figure 50: A) Radical ion e-PRC aminooxygenation of aryl olefins using TAC+ as an electro-activated photocatal...
Figure 51: A) Recycling e-PRC C–H alkylation of heteroarenes with organic trifluoroborates using Mes-Acr+ as p...
Figure 52: A) Recycling e-PRC decarboxylative C–H alkylation of heteroarenes using CeCl3·7H2O as catalyst. B) ...
Figure 53: A) Recycling e-PRC decarboxylative C–H alkylation of heteroarenes using Fe(NH4)2(SO4)2·6H2O as cata...
Figure 54: A) Recycling e-PRC C–H alkylation of heteroarenes with alkyl oxalates and 4CzIPN as photocatalyst. ...
Figure 55: A) Recycling e-PRC decarboxylative C–H carbamoylation of heteroarenes using 4CzIPN as photocatalyst...
Figure 56: A) Photoelectrochemical HAT-mediated hydrocarbon activation via the chlorine radical. B) Proposed m...
Figure 57: A) Selected examples from the substrate scope. B) Gram and decagram scale semi-continuous flow PEC ...
Figure 58: A) Photoelectrochemical HAT-mediated dehydrogenative coupling of benzothiazoles with aliphatic C–H ...
Figure 59: A) Photoelectrochemical HAT activation of ethers using electro-activated TAC+ as photocatalyst. B) ...
Figure 60: Selected examples from the substrate scope.
Figure 61: A) Photoelectrochemical HAT-mediated synthesis of alkylated benzimidazo-fused isoquinolinones using...
Figure 62: A) Decoupled photoelectrochemical cerium-catalyzed oxydichlorination of alkynes using CeCl3 as cata...
Figure 63: Proposed decoupled photoelectrochemical mechanism.
Figure 64: A) Decoupled photoelectrochemical ring-opening bromination of tertiary cycloalkanols using MgBr2 as...
Figure 65: A) Recycling e-PRC ring-opening functionalization of cycloalkanols using CeCl3 as catalyst. B) Prop...
Figure 66: Selected examples from the substrate scope of the PEC ring-opening functionalization.
Figure 67: A) Radical ion e-PRC reduction of chloro- and bromoarenes using DCA as catalyst and various accepto...
Figure 68: A) Screening of different phthalimide derivatives as catalyst for the e-PRC reduction of aryl halid...
Figure 69: Screening of different organic catalysts for the e-PRC reduction of trialkylanilium salts.
Figure 70: A) e-PRC reduction of phosphonated phenols and anilinium salts. B) Selected examples from the subst...
Figure 71: A) ConPET and e-PRC reduction of 4-bromobenzonitrile using a naphthalene diimide (NDI) precatalyst ...
Figure 72: A) Radical ion e-PRC reduction of phosphinated aliphatic alcohols with n-BuO-NpMI as catalyst. B) C...
Figure 73: Selected examples from the substrate scope.
Figure 74: A) Recycling e-PRC reductive dimerization of benzylic chlorides using a [Cu2] catalyst. B) Proposed...
Figure 75: A) Decoupled photoelectrochemical C–H alkylation of heteroarenes through deamination of Katritzky s...
Figure 76: Proposed mechanism by Chen and co-workers.
Beilstein J. Org. Chem. 2023, 19, 1008–1014, doi:10.3762/bjoc.19.76
Graphical Abstract
Figure 1: Representative examples of N-arylamines.
Scheme 1: N-Arylation of amines with hypervalent iodine reagents.
Scheme 2: N-Arylation of primary amines with iodonium ylide. Reaction conditions: 0.2 mmol aniline 1, 0.24 mm...
Scheme 3: N-Arylation of secondary amines with iodonium ylide.
Beilstein J. Org. Chem. 2023, 19, 982–990, doi:10.3762/bjoc.19.73
Graphical Abstract
Scheme 1: Various cycloaddition reactions of 5,6-unsymmetric 1,4-dihydropyridines.
Figure 1: Single crystal structure of the compound 4k.
Figure 2: Single crystal structure of compound 5a.
Figure 3: Single crystal structure of compound 6f.
Scheme 2: Plausible reaction mechanism for the various products 4, 5, and 6.
Beilstein J. Org. Chem. 2023, 19, 928–955, doi:10.3762/bjoc.19.71
Graphical Abstract
Figure 1: Various pyrrole containing molecules.
Scheme 1: Various synthestic protocols for the synthesis of pyrroles.
Figure 2: A tree-diagram showing various conventional and green protocols for Clauson-Kaas pyrrole synthesis.
Scheme 2: A general reaction of Clauson–Kaas pyrrole synthesis and proposed mechanism.
Scheme 3: AcOH-catalyzed synthesis of pyrroles 5 and 7.
Scheme 4: Synthesis of N-substituted pyrroles 9.
Scheme 5: P2O5-catalyzed synthesis of N-substituted pyrroles 11.
Scheme 6: p-Chloropyridine hydrochloride-catalyzed synthesis of pyrroles 13.
Scheme 7: TfOH-catalyzed synthesis of N-sulfonylpyrroles 15, N-sulfonylindole 16, N-sulfonylcarbazole 17.
Scheme 8: Scandium triflate-catalyzed synthesis of N-substituted pyrroles 19.
Scheme 9: MgI2 etherate-catalyzed synthesis and proposed mechanism of N-arylpyrrole derivatives 21.
Scheme 10: Nicotinamide catalyzed synthesis of pyrroles 23.
Scheme 11: ZrOCl2∙8H2O catalyzed synthesis and proposed mechanism of pyrrole derivatives 25.
Scheme 12: AcONa catalyzed synthesis of N-substituted pyrroles 27.
Scheme 13: Squaric acid-catalyzed synthesis and proposed mechanism of N-substituted pyrroles 29.
Figure 3: Reusability of catalyst γ-Fe2O3@SiO2-Sb-IL in six cycles.
Scheme 14: Magnetic nanoparticle-supported antimony catalyst used in the synthesis of N-substituted pyrroles 31...
Scheme 15: Iron(III) chloride-catalyzed synthesis of N-substituted pyrroles 33.
Scheme 16: Copper-catalyzed Clauson–Kaas synthesis and mechanism of pyrroles 35.
Scheme 17: β-CD-SO3H-catalyzed synthesis and proposed mechanism of pyrroles 37.
Figure 4: Recyclability of β-cyclodextrin-SO3H.
Scheme 18: Solvent-free and catalyst-free synthesis and plausible mechanism of N-substituted pyrroles 39.
Scheme 19: Nano-sulfated TiO2-catalyzed synthesis of N-substituted pyrroles 41.
Figure 5: Plausible mechanism for the formation of N-substituted pyrroles catalyzed by nano-sulfated TiO2 cat...
Scheme 20: Copper nitrate-catalyzed Clauson–Kaas synthesis and mechanism of N-substituted pyrroles 43.
Scheme 21: Synthesis of N-substituted pyrroles 45 by using Co catalyst Co/NGr-C@SiO2-L.
Scheme 22: Zinc-catalyzed synthesis of N-arylpyrroles 47.
Scheme 23: Silica sulfuric acid-catalyzed synthesis of pyrrole derivatives 49.
Scheme 24: Bismuth nitrate-catalyzed synthesis of pyrroles 51.
Scheme 25: L-(+)-tartaric acid-choline chloride-catalyzed Clauson–Kaas synthesis and plausible mechanism of py...
Scheme 26: Microwave-assisted synthesis of N-substituted pyrroles 55 in AcOH or water.
Scheme 27: Synthesis of pyrrole derivatives 57 using a nano-organocatalyst.
Figure 6: Nano-ferric supported glutathione organocatalyst.
Scheme 28: Microwave-assisted synthesis of N-substituted pyrroles 59 in water.
Scheme 29: Iodine-catalyzed synthesis and proposed mechanism of pyrroles 61.
Scheme 30: H3PW12O40/SiO2-catalyzed synthesis of N-substituted pyrroles 63.
Scheme 31: Fe3O4@-γ-Fe2O3-SO3H-catalyzed synthesis of pyrroles 65.
Scheme 32: Mn(NO3)2·4H2O-catalyzed synthesis and proposed mechanism of pyrroles 67.
Scheme 33: p-TsOH∙H2O-catalyzed (method 1) and MW-assisted (method 2) synthesis of N-sulfonylpyrroles 69.
Scheme 34: ([hmim][HSO4]-catalyzed Clauson–Kaas synthesis of pyrroles 71.
Scheme 35: Synthesis of N-substituted pyrroles 73 using K-10 montmorillonite catalyst.
Scheme 36: CeCl3∙7H2O-catalyzed Clauson–Kaas synthesis of pyrroles 75.
Scheme 37: Synthesis of N-substituted pyrroles 77 using Bi(NO3)3∙5H2O.
Scheme 38: Oxone-catalyzed synthesis and proposed mechanism of N-substituted pyrroles 79.
Beilstein J. Org. Chem. 2023, 19, 901–908, doi:10.3762/bjoc.19.68
Graphical Abstract
Scheme 1: Representative nitrile-containing functional materials, drug carriers, and medicines.
Scheme 2: Activating protocol of cyclobutanone oximes.
Scheme 3: Substrate scope of δ-olefin-containing aliphatic nitriles. Reaction conditions: A mixture of cyclob...
Scheme 4: Competition between two reactions caused by the reduction of base equivalent.
Scheme 5: Mechanistic investigations.
Scheme 6: A proposed plausible mechanism.
Beilstein J. Org. Chem. 2023, 19, 881–888, doi:10.3762/bjoc.19.65
Graphical Abstract
Scheme 1: Concept of this work.
Scheme 2: Initial experiments for the trapping of the intermediate enolate Enl-1a with tropylium NTf2.
Scheme 3: The reaction scope.
Figure 1: Comparison of DFT-calculated and experimental ECD of (2R,3R)-4 and (2S,3R)-4.
Figure 2: DFT calculated (ωB97X-D4/def2-TZVPPD//PBEh-3c/def2-mSVP) HOMO energies and NBO charges for represen...
Beilstein J. Org. Chem. 2023, 19, 820–863, doi:10.3762/bjoc.19.62
Graphical Abstract
Figure 1: Representative examples of bioactive natural products and FDA-approved drugs containing a pyridine ...
Scheme 1: Classical and traditional methods for the synthesis of functionalized pyridines.
Scheme 2: Rare earth metal (Ln)-catalyzed pyridine C–H alkylation.
Scheme 3: Pd-catalyzed C–H alkylation of pyridine N-oxide.
Scheme 4: CuI-catalyzed C–H alkylation of N-iminopyridinium ylides with tosylhydrazones (A) and a plausible r...
Scheme 5: Zirconium complex-catalyzed pyridine C–H alkylation.
Scheme 6: Rare earth metal-catalyzed pyridine C–H alkylation with nonpolar unsaturated substrates.
Scheme 7: Heterobimetallic Rh–Al complex-catalyzed ortho-C–H monoalkylation of pyridines.
Scheme 8: Mono(phosphinoamido)-rare earth complex-catalyzed pyridine C–H alkylation.
Scheme 9: Rhodium-catalyzed pyridine C–H alkylation with acrylates and acrylamides.
Scheme 10: Ni–Al bimetallic system-catalyzed pyridine C–H alkylation.
Scheme 11: Iridium-catalyzed pyridine C–H alkylation.
Scheme 12: para-C(sp2)–H Alkylation of pyridines with alkenes.
Scheme 13: Enantioselective pyridine C–H alkylation.
Scheme 14: Pd-catalyzed C2-olefination of pyridines.
Scheme 15: Ru-catalyzed C-6 (C-2)-propenylation of 2-arylated pyridines.
Scheme 16: C–H addition of allenes to pyridines catalyzed by half-sandwich Sc metal complex.
Scheme 17: Pd-catalyzed stereodivergent synthesis of alkenylated pyridines.
Scheme 18: Pd-catalyzed ligand-promoted selective C3-olefination of pyridines.
Scheme 19: Mono-N-protected amino acids in Pd-catalyzed C3-alkenylation of pyridines.
Scheme 20: Amide-directed and rhodium-catalyzed C3-alkenylation of pyridines.
Scheme 21: Bimetallic Ni–Al-catalyzed para-selective alkenylation of pyridine.
Scheme 22: Arylboronic ester-assisted pyridine direct C–H arylation.
Scheme 23: Pd-catalyzed C–H arylation/benzylation with toluene.
Scheme 24: Pd-catalyzed pyridine C–H arylation with potassium aryl- and heteroaryltrifluoroborates.
Scheme 25: Transient activator strategy in pyridine C–H biarylation.
Scheme 26: Ligand-promoted C3-arylation of pyridine.
Scheme 27: Pd-catalyzed arylation of nicotinic and isonicotinic acids.
Scheme 28: Iron-catalyzed and imine-directed C–H arylation of pyridines.
Scheme 29: Pd–(bipy-6-OH) cooperative system-mediated direct pyridine C3-arylation.
Scheme 30: Pd-catalyzed pyridine N-oxide C–H arylation with heteroarylcarboxylic acids.
Scheme 31: Pd-catalyzed C–H cross-coupling of pyridine N-oxides with five-membered heterocycles.
Scheme 32: Cu-catalyzed dehydrative biaryl coupling of azine(pyridine) N-oxides and oxazoles.
Scheme 33: Rh(III)-catalyzed cross dehydrogenative C3-heteroarylation of pyridines.
Scheme 34: Pd-catalyzed C3-selective arylation of pyridines.
Scheme 35: Rhodium-catalyzed oxidative C–H annulation of pyridines to quinolines.
Scheme 36: Rhodium-catalyzed and NHC-directed C–H annulation of pyridine.
Scheme 37: Ni/NHC-catalyzed regio- and enantioselective C–H cyclization of pyridines.
Scheme 38: Rare earth metal-catalyzed intramolecular C–H cyclization of pyridine to azaindolines.
Scheme 39: Rh-catalyzed alkenylation of bipyridine with terminal silylacetylenes.
Scheme 40: Rollover cyclometallation in Rh-catalyzed pyridine C–H functionalization.
Scheme 41: Rollover pathway in Rh-catalyzed C–H functionalization of N,N,N-tridentate chelating compounds.
Scheme 42: Pd-catalyzed rollover pathway in bipyridine-6-carboxamides C–H arylation.
Scheme 43: Rh-catalyzed C3-acylmethylation of bipyridine-6-carboxamides with sulfoxonium ylides.
Scheme 44: Rh-catalyzed C–H functionalization of bipyridines with alkynes.
Scheme 45: Rh-catalyzed C–H acylmethylation and annulation of bipyridine with sulfoxonium ylides.
Scheme 46: Iridium-catalyzed C4-borylation of pyridines.
Scheme 47: C3-Borylation of pyridines.
Scheme 48: Pd-catalyzed regioselective synthesis of silylated dihydropyridines.
Beilstein J. Org. Chem. 2023, 19, 771–777, doi:10.3762/bjoc.19.57
Graphical Abstract
Scheme 1: Various synthetic approaches to N-arylsulfonylimines.
Scheme 2: Substrate scope for the synthesis of N-arylsulfonylimines. Reaction conditions: 1a (0.25 mmol), K2S2...
Scheme 3: Tandem “one-pot” synthesis of N-heterocycles. Reaction conditions: 1a (0.25 mmol), K2S2O8 (0.5 mmol...
Scheme 4: Control experiment with TEMPO.
Scheme 5: Plausible mechanism for the K2S2O8-induced oxidation of N-(arylsulfonyl)benzylamines.
Scheme 6: Plausible mechanism for one-pot synthesis of N-heterocycles.
Beilstein J. Org. Chem. 2023, 19, 593–634, doi:10.3762/bjoc.19.44
Graphical Abstract
Scheme 1: General scheme depicting tandem reactions based on an asymmetric conjugate addition followed by an ...
Scheme 2: Cu-catalyzed tandem conjugate addition of R2Zn/aldol reaction with chiral acetals.
Scheme 3: Cu-catalyzed asymmetric desymmetrization of cyclopentene-1,3-diones using a tandem conjugate additi...
Scheme 4: Stereocontrolled assembly of dialkylzincs, cyclic enones, and sulfinylimines utilizing a Cu-catalyz...
Scheme 5: Cu-catalyzed tandem conjugate addition/Mannich reaction (A). Access to chiral isoindolinones and tr...
Scheme 6: Cu-catalyzed tandem conjugate addition/nitro-Mannich reaction (A) with syn–anti or syn–syn selectiv...
Figure 1: Various chiral ligands utilized for the tandem conjugate addition/Michael reaction sequences.
Scheme 7: Cu-catalyzed tandem conjugate addition/Michael reaction: side-product formation with chalcone (A) a...
Scheme 8: Zn enolate trapping using allyl iodides (A), Stork–Jung vinylsilane reagents (B), and allyl bromide...
Scheme 9: Cu-catalyzed tandem conjugate addition/acylation through Li R2Zn enolate (A). A four-component coup...
Scheme 10: Selected examples for the Cu-catalyzed tandem conjugate addition/trifluoromethylthiolation sequence....
Scheme 11: Zn enolates trapped by vinyloxiranes: synthesis of allylic alcohols.
Scheme 12: Stereoselective cyclopropanation of Mg enolates formed by ACA of Grignard reagents to chlorocrotona...
Scheme 13: Domino aldol reactions of Mg enolates formed from coumarin and chromone.
Scheme 14: Oxidative coupling of ACA-produced Mg enolates.
Scheme 15: Tandem ACA of Grignard reagents to enones and Mannich reaction.
Scheme 16: Diastereodivergent Mannich reaction of Mg enolates with differently N-protected imines.
Scheme 17: Tandem Grignard–ACA–Mannich using Taddol-based phosphine-phosphite ligands.
Scheme 18: Tandem reaction of Mg enolates with aminomethylating reagents.
Scheme 19: Tandem reaction composed of Grignard ACA to alkynyl enones.
Scheme 20: Rh/Cu-catalyzed tandem reaction of diazo enoates leading to cyclobutanes.
Scheme 21: Tandem Grignard-ACA of cyclopentenones and alkylation of enolates.
Scheme 22: Tandem ACA of Grignard reagents followed by enolate trapping reaction with onium compounds.
Scheme 23: Mg enolates generated from unsaturated lactones in reaction with activated alkenes.
Scheme 24: Lewis acid mediated ACA to amides and SN2 cyclization of a Br-appended enolate.
Scheme 25: Trapping reactions of aza-enolates with Michael acceptors.
Scheme 26: Si enolates generated by TMSOTf-mediated ACA of Grignard reagents and enolate trapping reaction wit...
Scheme 27: Trapping reactions of enolates generated from alkenyl heterocycles (A) and carboxylic acids (B) wit...
Scheme 28: Reactions of heterocyclic Mg enolates with onium compounds.
Scheme 29: Synthetic transformations of cycloheptatrienyl and benzodithiolyl substituents.
Scheme 30: Aminomethylation of Al enolates generated by ACA of trialkylaluminum reagents.
Scheme 31: Trapping reactions of enolates with activated alkenes.
Scheme 32: Alkynylation of racemic aluminum or magnesium enolates.
Scheme 33: Trapping reactions of Zr enolates generated by Cu-ACA of organozirconium reagents.
Scheme 34: Chloromethylation of Zr enolates using the Vilsmeier–Haack reagent.
Scheme 35: Tandem conjugate borylation with subsequent protonation or enolate trapping by an electrophile.
Scheme 36: Tandem conjugate borylation/aldol reaction of cyclohexenones.
Scheme 37: Selected examples for the tandem asymmetric borylation/intramolecular aldol reaction; synthesis of ...
Scheme 38: Cu-catalyzed tandem methylborylation of α,β-unsaturated phosphine oxide in the presence of (R,Sp)-J...
Scheme 39: Cu-catalyzed tandem transannular conjugated borylation/aldol cyclization of macrocycles containing ...
Scheme 40: Stereoselective tandem conjugate borylation/Mannich cyclization: selected examples (A) and a multi-...
Scheme 41: Some examples of Cu-catalyzed asymmetric tandem borylation/aldol cyclization (A). Application to di...
Scheme 42: Atropisomeric P,N-ligands used in tandem conjugate borylation/aldol cyclization sequence.
Scheme 43: Selected examples for the enantioselective Cu-catalyzed borylation/intramolecular Michael addition ...
Scheme 44: Selected examples for the preparation of enantioenriched spiroindanes using a Cu-catalyzed tandem c...
Scheme 45: Enantioselective conjugate borylation of cyclobutene-1-carboxylic acid diphenylmethyl ester 175 wit...
Scheme 46: Cu-catalyzed enantioselective tandem conjugate silylation of α,β-unsaturated ketones with subsequen...
Scheme 47: Cu-catalyzed enantioselective tandem conjugate silylation of α,β-unsaturated ketones with subsequen...
Scheme 48: Cu-catalyzed tandem conjugate silylation/aldol condensation. The diastereoselectivity is controlled...
Scheme 49: Chiral Ru-catalyzed three-component coupling reaction.
Scheme 50: Rh-Phebox complex-catalyzed reductive cyclization and subsequent reaction with Michael acceptors th...
Scheme 51: Rh-catalyzed tandem asymmetric conjugate alkynylation/aldol reaction (A) and subsequent spiro-cycli...
Scheme 52: Rh-bod complex-catalyzed tandem asymmetric conjugate arylation/intramolecular aldol addition (A). S...
Scheme 53: Co-catalyzed C–H-bond activation/asymmetric conjugate addition/aldol reaction.
Scheme 54: (Diisopinocampheyl)borane-promoted 1,4-hydroboration of α,β-unsaturated morpholine carboxamides and...
Figure 2: Some examples of total syntheses that have been recently reviewed.
Scheme 55: Stereoselective synthesis of antimalarial prodrug (+)-artemisinin utilizing a tandem conjugate addi...
Scheme 56: Amphilectane and serrulatane diterpenoids: preparation of chiral starting material via asymmetric t...
Scheme 57: Various asymmetric syntheses of pleuromutilin and related compounds based on a tandem conjugate add...
Scheme 58: Total synthesis of glaucocalyxin A utilizing a tandem conjugate addition/acylation reaction sequenc...
Scheme 59: Installation of the exocyclic double bond using a tandem conjugate addition/aminomethylation sequen...
Scheme 60: Synthesis of the taxol core using a tandem conjugate addition/enolate trapping sequence with Vilsme...
Scheme 61: Synthesis of the tricyclic core of 12-epi-JBIR-23/24 utilizing a Rh-catalyzed asymmetric conjugate ...
Scheme 62: Total synthesis of (−)-peyssonoside A utilizing a Cu-catalyzed enantioselective tandem conjugate ad...
Beilstein J. Org. Chem. 2023, 19, 582–592, doi:10.3762/bjoc.19.43
Graphical Abstract
Scheme 1: C3-Functionalization of furfural derivatives by C–H activation, a) in batch: previous works, and b)...
Scheme 2: C3-alkylation of bidentate imine 1 performed in batch.
Scheme 3: Optimization of the heating for the alkylation reaction on the homemade pulsed-flow setup.
Scheme 4: Proposed reaction mechanism for the alkylation reaction with formation of ruthenium aggregates and ...
Scheme 5: A) Isolation test of a reaction intermediate; B) XPS and TEM (in ethanol) of the recovered solid ph...
Scheme 6: Ruthenium aggregate-catalyzed alkylation reaction.
Scheme 7: Scope of continuous flow furfural derivative alkylation reaction.
Scheme 8: Scaling up comparison: batch and continuous flow conditions.
Beilstein J. Org. Chem. 2023, 19, 575–581, doi:10.3762/bjoc.19.42
Graphical Abstract
Figure 1: (a) Exploitation of an EDA complex in organic synthesis. (b) This work: use of halogen-bonded compl...
Figure 2: Optical absorption spectra recorded in acetonitrile in 1 cm path quartz cuvettes. [DABCO]: 0.5 M; [...
Figure 3: 1H NMR titration of DABCO in a solution of 2a in ACN-d3 to detect their halogen-bonding association...
Figure 4: Proposed reaction mechanism for the photochemical alkylation of 1a with the α-iodosulfone 2a in the...
Scheme 1: Study of scope of the HAS reaction between indoles 1 and α-iodosulfones 2. Yields in parentheses we...
Beilstein J. Org. Chem. 2023, 19, 487–540, doi:10.3762/bjoc.19.38
Graphical Abstract
Figure 1: Ring-strain energies of homobicyclic and heterobicyclic alkenes in kcal mol−1. a) [2.2.1]-Bicyclic ...
Figure 2: a) Exo and endo face descriptions of bicyclic alkenes. b) Reactivity comparisons for different β-at...
Scheme 1: Ni-catalyzed ring-opening/cyclization cascade of heterobicyclic alkenes 1 with alkyl propiolates 2 ...
Scheme 2: Ni-catalyzed ring-opening/cyclization cascade of heterobicyclic alkenes 8 with β-iodo-(Z)-propenoat...
Scheme 3: Ni-catalyzed two- and three-component difunctionalizations of norbornene derivatives 15 with alkyne...
Scheme 4: Ni-catalyzed intermolecular three-component difunctionalization of oxabicyclic alkenes 1 with alkyn...
Scheme 5: Ni-catalyzed intermolecular three-component carboacylation of norbornene derivatives 15.
Scheme 6: Photoredox/Ni dual-catalyzed coupling of 4-alkyl-1,4-dihydropyridines 31 with heterobicyclic alkene...
Scheme 7: Photoredox/Ni dual-catalyzed coupling of α-amino radicals with heterobicyclic alkenes 30.
Scheme 8: Cu-catalyzed rearrangement/allylic alkylation of 2,3-diazabicyclo[2.2.1]heptenes 47 with Grignard r...
Scheme 9: Cu-catalyzed aminoboration of bicyclic alkenes 1 with bis(pinacolato)diboron (B2pin2) (53) and O-be...
Scheme 10: Cu-catalyzed borylalkynylation of oxabenzonorbornadiene (30b) with B2pin2 (53) and bromoalkynes 62.
Scheme 11: Cu-catalyzed borylacylation of bicyclic alkenes 1.
Scheme 12: Cu-catalyzed diastereoselective 1,2-difunctionalization of oxabenzonorbornadienes 30 for the synthe...
Scheme 13: Fe-catalyzed carbozincation of heterobicyclic alkenes 1 with arylzinc reagents 74.
Scheme 14: Co-catalyzed addition of arylzinc reagents of norbornene derivatives 15.
Scheme 15: Co-catalyzed ring-opening/dehydration of oxabicyclic alkenes 30 via C–H activation of arenes.
Scheme 16: Co-catalyzed [3 + 2] annulation/ring-opening/dehydration domino reaction of oxabicyclic alkenes 1 w...
Scheme 17: Co-catalyzed enantioselective carboamination of bicyclic alkenes 1 via C–H functionalization.
Scheme 18: Ru-catalyzed cyclization of oxabenzonorbornene derivatives with propargylic alcohols for the synthe...
Scheme 19: Ru-catalyzed coupling of oxabenzonorbornene derivatives 30 with propargylic alcohols and ethers 106...
Scheme 20: Ru-catalyzed ring-opening/dehydration of oxabicyclic alkenes via the C–H activation of anilides.
Scheme 21: Ru-catalyzed of azabenzonorbornadiene derivatives with arylamides.
Scheme 22: Rh-catalyzed cyclization of bicyclic alkenes with arylboronate esters 118.
Scheme 23: Rh-catalyzed cyclization of bicyclic alkenes with dienyl- and heteroaromatic boronate esters.
Scheme 24: Rh-catalyzed domino lactonization of doubly bridgehead-substituted oxabicyclic alkenes with seconda...
Scheme 25: Rh-catalyzed domino carboannulation of diazabicyclic alkenes with 2-cyanophenylboronic acid and 2-f...
Scheme 26: Rh-catalyzed synthesis of oxazolidinone scaffolds 147 through a domino ARO/cyclization of oxabicycl...
Scheme 27: Rh-catalyzed oxidative coupling of salicylaldehyde derivatives 151 with diazabicyclic alkenes 130a.
Scheme 28: Rh-catalyzed reaction of O-acetyl ketoximes with bicyclic alkenes for the synthesis of isoquinoline...
Scheme 29: Rh-catalyzed domino coupling reaction of 2-phenylpyridines 165 with oxa- and azabicyclic alkenes 30....
Scheme 30: Rh-catalyzed domino dehydrative naphthylation of oxabenzonorbornadienes 30 with N-sulfonyl 2-aminob...
Scheme 31: Rh-catalyzed domino dehydrative naphthylation of oxabenzonorbornadienes 30 with arylphosphine deriv...
Scheme 32: Rh-catalyzed domino ring-opening coupling reaction of azaspirotricyclic alkenes using arylboronic a...
Scheme 33: Tandem Rh(III)/Sc(III)-catalyzed domino reaction of oxabenzonorbornadienes 30 with alkynols 184 dir...
Scheme 34: Rh-catalyzed asymmetric domino cyclization and addition reaction of 1,6-enynes 194 and oxa/azabenzo...
Scheme 35: Rh/Zn-catalyzed domino ARO/cyclization of oxabenzonorbornadienes 30 with phosphorus ylides 201.
Scheme 36: Rh-catalyzed domino ring opening/lactonization of oxabenzonorbornadienes 30 with 2-nitrobenzenesulf...
Scheme 37: Rh-catalyzed domino C–C/C–N bond formation of azabenzonorbornadienes 30 with aryl-2H-indazoles 210.
Scheme 38: Rh/Pd-catalyzed domino synthesis of indole derivatives with 2-(phenylethynyl)anilines 212 and oxabe...
Scheme 39: Rh-catalyzed domino carborhodation of heterobicyclic alkenes 30 with B2pin2 (53).
Scheme 40: Rh-catalyzed three-component 1,2-carboamidation reaction of bicyclic alkenes 30 with aromatic and h...
Scheme 41: Pd-catalyzed diarylation and dialkenylation reactions of norbornene derivatives.
Scheme 42: Three-component Pd-catalyzed arylalkynylation reactions of bicyclic alkenes.
Scheme 43: Three-component Pd-catalyzed arylalkynylation reactions of norbornene and DFT mechanistic study.
Scheme 44: Pd-catalyzed three-component coupling N-tosylhydrazones 236, aryl halides 66, and norbornene (15a).
Scheme 45: Pd-catalyzed arylboration and allylboration of bicyclic alkenes.
Scheme 46: Pd-catalyzed, three-component annulation of aryl iodides 66, alkenyl bromides 241, and bicyclic alk...
Scheme 47: Pd-catalyzed double insertion/annulation reaction for synthesizing tetrasubstituted olefins.
Scheme 48: Pd-catalyzed aminocyclopropanation of bicyclic alkenes 1 with 5-iodopent-4-enylamine derivatives 249...
Scheme 49: Pd-catalyzed, three-component coupling of alkynyl bromides 62 and norbornene derivatives 15 with el...
Scheme 50: Pd-catalyzed intramolecular cyclization/ring-opening reaction of heterobicyclic alkenes 30 with 2-i...
Scheme 51: Pd-catalyzed dimer- and trimerization of oxabenzonorbornadiene derivatives 30 with anhydrides 268.
Scheme 52: Pd-catalyzed Catellani-type annulation and retro-Diels–Alder of norbornadiene 15b yielding fused xa...
Scheme 53: Pd-catalyzed hydroarylation and heteroannulation of urea-derived bicyclic alkenes 158 and aryl iodi...
Scheme 54: Access to fused 8-membered sulfoximine heterocycles 284/285 via Pd-catalyzed Catellani annulation c...
Scheme 55: Pd-catalyzed 2,2-bifunctionalization of bicyclic alkenes 1 generating spirobicyclic xanthone deriva...
Scheme 56: Pd-catalyzed Catellani-type annulation and retro-Diels–Alder of norbornadiene (15b) producing subst...
Scheme 57: Pd-catalyzed [2 + 2 + 1] annulation furnishing bicyclic-fused indanes 281 and 283.
Scheme 58: Pd-catalyzed ring-opening/ring-closing cascade of diazabicyclic alkenes 130a.
Scheme 59: Pd-NHC-catalyzed cyclopentannulation of diazabicyclic alkenes 130a.
Scheme 60: Pd-catalyzed annulation cascade generating diazabicyclic-fused indanones 292 and indanols 294.
Scheme 61: Pd-catalyzed skeletal rearrangement of spirotricyclic alkenes 176 towards large polycyclic benzofur...
Scheme 62: Pd-catalyzed oxidative annulation of aromatic enamides 298 and diazabicyclic alkenes 130a.
Scheme 63: Accessing 3,4,5-trisubstituted cyclopentenes 300, 301, 302 via the Pd-catalyzed domino reaction of ...
Scheme 64: Palladacycle-catalyzed ring-expansion/cyclization domino reactions of terminal alkynes and bicyclic...
Scheme 65: Pd-catalyzed carboesterification of norbornene (15a) with alkynes, furnishing α-methylene γ-lactone...
Beilstein J. Org. Chem. 2023, 19, 349–379, doi:10.3762/bjoc.19.29
Graphical Abstract
Figure 1: Alkyne–azide "click reaction".
Figure 2: β- and meso-triazole-linked porphyrin.
Scheme 1: Synthesis of β-triazole-linked porphyrins 3a–c.
Scheme 2: Synthesis of β-triazole-bridged porphyrin-coumarin conjugates 11–20.
Scheme 3: Synthesis of β-triazole-bridged porphyrin-xanthone conjugates 23–27 and xanthone-bridged β-triazolo...
Scheme 4: Synthesis of meso-triazoloporphyrins 32a–c and triazole-bridged diporphyrins 34.
Scheme 5: Synthesis of meso-triazole-linked porphyrin-ferrocene conjugates 37a–d.
Scheme 6: Synthesis of meso-triazole-linked porphyrin conjugates 40a,b and 41a,b.
Scheme 7: Synthesis of meso-triazole-linked glycoporphyrins 43a–c.
Scheme 8: Synthesis of meso-triazole-linked porphyrin-coumarin conjugates 44–48.
Scheme 9: Synthesis of meso-triazole-bridged porphyrin-DNA conjugate 50.
Scheme 10: Synthesis of meso-linked porphyrin-triazole conjugates 53 and 57.
Scheme 11: Synthesis of meso-triazole-linked porphyrin-corrole conjugate 60.
Scheme 12: Synthesis of porphyrin conjugates 64a,b and 67a,b. Reaction conditions: (i) CuSO4, sodium ascorbate...
Scheme 13: Synthesis of meso-triazole-bridged porphyrin-quinolone conjugates 70a–e.
Scheme 14: Synthesis of meso-triazole-linked porphyrin-fluorescein dyad 73.
Scheme 15: Synthesis of meso-triazole-linked porphyrin-carborane conjugates 76a,b.
Scheme 16: Synthesis of meso-triazole-bridged porphyrin-BODIPY conjugates 78 and 80.
Scheme 17: Synthesis of meso-triazole-linked cationic porphyrin conjugates 85 and 87. Reaction conditions: (i)...
Scheme 18: Synthesis of meso-triazole-cobalt-porphyrin diimine-dioxime conjugate 91. Reactions conditions: (i)...
Scheme 19: Synthesis of triazole-linked porphyrin-bearing N-doped graphene hybrid 96.
Scheme 20: Synthesis of meso-triazole-linked porphyrin-fullerene dyads 100a–d and 104a,b.
Scheme 21: Synthesis of meso-triazole-bridged diporphyrin conjugates 107 and 108.
Scheme 22: Synthesis of porphyrin-ruthenium (II) conjugates 112a,b and 116a,b. Reaction conditions: (i) Zn(OAc)...
Scheme 23: Synthesis of meso-triazole-linked porphyrin dyad 119 and triad 121.
Scheme 24: Synthesis of di-triazole-bridged porphyrin-β-CD conjugate 126.
Scheme 25: Synthesis of meso-triazole-bridged porphyrin star trimer 129.
Scheme 26: Synthesis of 1,2,3-triazole-linked porphyrin-β-CD conjugates 131a,b.
Scheme 27: Synthesis of tritriazole-bridged porphyrin-lantern-DNA sequence 134.
Scheme 28: Synthesis of meso-triazole-linked porphyrin-polymer conjugates 137 and 139.
Scheme 29: Synthesis of triazole-linked capped porphyrin 142; Reaction conditions: method A: 10% H2O in THF, C...
Scheme 30: Synthesis of meso-tetratriazole-linked porphyrin-maleimine conjugates 145a–c.
Scheme 31: Synthesis of meso-tetratriazole-linked porphyrin-cholic acid complex 148a,b.
Scheme 32: Synthesis of meso-tetratriazole-linked porphyrin conjugates 151–153.
Scheme 33: Synthesis of meso-tetratrizole-porphyrin-carborane conjugates 155, 156 and 158a–c.
Scheme 34: Synthesis of meso-tetratriazole-porphyrin-cardanol conjugates 160 and 162.
Scheme 35: Synthesis of meso-tetratriazole-linked porphyrin-BODIPY conjugate 164.
Scheme 36: Synthesis of meso-tetratriazole-linked porphyrin-β-CD conjugates 166a,b.
Scheme 37: Synthesis of tetratriazole-bridged meso-arylporphyrins 171a–c and 172a–c.
Scheme 38: Synthesis of octatriazole-bridged porphyrin-β-CD conjugate 174 and porphyrin-adamantane conjugates ...
Beilstein J. Org. Chem. 2023, 19, 317–324, doi:10.3762/bjoc.19.27
Graphical Abstract
Figure 1: Nitrogen-containing iodolium and iodonium salts.
Figure 2: Synthesis of a set of azoiodazinium salts 5. Method A: Iodoarene 4 (200 µmol) and mCPBA (1.1 equiv)...
Figure 3: Single crystal structures (ORTEP drawing with 50% probability) of the pyrazole-coordinated salt 5bb...
Scheme 1: Derivatizations of the iodonium salt 5aa. a) Ac2O, CuSO4·5H2O, NaOAc, AcOH, 120 °C, 5 h; b) S8/Se/T...
Scheme 2: Post-functionalization of mono- and dicationic iodonium salts under preservation of the hypervalent...
Beilstein J. Org. Chem. 2023, 19, 245–281, doi:10.3762/bjoc.19.23
Graphical Abstract
Figure 1: Examples of terpenes containing a bicyclo[3.6.0]undecane motif.
Figure 2: Commercially available first and second generation Grubbs and Hoveyda–Grubbs catalysts.
Figure 3: Examples of strategies to access the fusicoccan and ophiobolin tricyclic core structure by RCM.
Scheme 1: Synthesis of bicyclic core structure 12 of ophiobolin M (13) and cycloaraneosene (14).
Scheme 2: Synthesis of the core structure 21 of ophiobolins and fusicoccanes.
Scheme 3: Ring-closing metathesis attempts starting from thioester 22.
Scheme 4: Total synthesis of ent-fusicoauritone (28).
Figure 4: General structure of ophiobolins and congeners.
Scheme 5: Total synthesis of (+)-ophiobolin A (8).
Scheme 6: Investigation of RCM for the synthesis of ophiobolin A (8). Path A) RCM with TBDPS-protected alcoho...
Scheme 7: Synthesis of the core structure of cotylenin A aglycon, cotylenol (50).
Scheme 8: Synthesis of tricyclic core structure of fusicoccans.
Scheme 9: Total synthesis of (−)-teubrevin G (59).
Scheme 10: Synthesis of the core skeleton 63 of the basmane family.
Scheme 11: Total synthesis of (±)-schindilactone A (68).
Scheme 12: Total synthesis of dactylol (72).
Scheme 13: Ring-closing metathesis for the total synthesis of (±)-asteriscanolide (2).
Scheme 14: Synthesis of the simplified skeleton of pleuromutilin (1).
Scheme 15: Total synthesis of (−)-nitidasin (93) using a ring-closing metathesis to construct the eight-member...
Scheme 16: Total synthesis of (±)-naupliolide (97).
Scheme 17: Synthesis of the A-B ring structure of fusicoccane (101).
Scheme 18: First attempts of TRCM of dienyne substrates.
Scheme 19: TRCM on optimized substrates towards the synthesis of ophiobolin A (8).
Scheme 20: Tandem ring-closing metathesis for the synthesis of variecolin intermediates 114 and 115.
Scheme 21: Synthesis of poitediol (118) using the allylsilane ring-closing metathesis.
Scheme 22: Access to scaffold 122 by a NHK coupling reaction.
Scheme 23: Key step to construct the [5-8] bicyclooctanone core of aquatolide (4).
Scheme 24: Initial strategy to access aquatolide (4).
Scheme 25: Synthetic plan to cotylenin A (130).
Scheme 26: [5-8] Bicyclic structure of brachialactone (7) constructed by a Mizoroki–Heck reaction.
Scheme 27: Influence of the replacement of the allylic alcohol moiety.
Scheme 28: Formation of variecolin intermediate 140 through a SmI2-mediated Barbier-type reaction.
Scheme 29: SmI2-mediated ketyl addition. Pleuromutilin (1) eight-membered ring closure via C5–C14 bond formati...
Scheme 30: SmI2-mediated dialdehyde cyclization cascade of [5-8-6] pleuromutilin scaffold 149.
Scheme 31: A) Modular synthetic route to mutilin and pleuromutilin family members by Herzon’s group. B) Scaffo...
Scheme 32: Photocatalyzed oxidative ring expansion in pleuromutilin (1) total synthesis.
Scheme 33: Reductive radical cascade cyclization route towards (−)-6-epi-ophiobolin N (168).
Scheme 34: Reductive radical cascade cyclization route towards (+)-6-epi-ophiobolin A (173).
Scheme 35: Radical 8-endo-trig-cyclization of a xanthate precursor.
Figure 5: Structural representations of hypoestin A (177), albolic acid (178), and ceroplastol II (179) beari...
Scheme 36: Synthesis of the common [5-8-5] tricyclic intermediate of hypoestin A (177), albolic acid (178), an...
Scheme 37: Asymmetric synthesis of hypoestin A (177), albolic acid (178), and ceroplastol II (179).
Figure 6: Scope of the Pauson–Khand reaction.
Scheme 38: Nazarov cyclization revealing the fusicoauritone core structure 192.
Scheme 39: Synthesis of fusicoauritone (28) through Nazarov cyclization.
Scheme 40: (+)-Epoxydictymene (5) synthesis through a Nicholas cyclization followed by a Pauson–Khand reaction...
Scheme 41: Synthesis of aquatolide (4) by a Mukaiyama-type aldolisation.
Scheme 42: Tandem Wolff/Cope rearrangement furnishing the A-B bicyclic moiety 204 of variecolin.
Scheme 43: Asymmetric synthesis of the A-B bicyclic core 205 and 206 of variecolin.
Scheme 44: Formation of [5-8]-fused rings by cyclization under thermal activation.
Scheme 45: Construction of the [5-8-6] tricyclic core structure of variecolin (3) by Diels–Alder reaction.
Scheme 46: Synthesis of the [6-4-8-5]-tetracyclic skeleton by palladium-mediated cyclization.
Scheme 47: Access to the [5-8] bicyclic core structure of asteriscanolide (227) through rhodium-catalyzed cycl...
Scheme 48: Total syntheses of asterisca-3(15),6-diene (230) and asteriscanolide (2) with a Rh-catalyzed cycliz...
Scheme 49: Photocyclization of 2-pyridones to access the [5-8-5] backbone of fusicoccanes.
Scheme 50: Total synthesis of (+)-asteriscunolide D (245) and (+)-aquatolide (4) through photocyclization.
Scheme 51: Biocatalysis pathway to construct the [5-8-5] tricyclic scaffold of brassicicenes.
Scheme 52: Influence of the CotB2 mutant over the cyclization’s outcome of GGDP.
Beilstein J. Org. Chem. 2023, 19, 231–244, doi:10.3762/bjoc.19.22
Graphical Abstract
Figure 1: Representative drug molecules based on pyrazole, thioamide, and amide derivatives.
Figure 2: Previous and present findings for the synthesis of thioamide derivatives.
Scheme 1: Synthesis of pyrazole C-3-tethered thioamides.
Scheme 2: Synthesis of pyrazole C-4-tethered thioamides.
Scheme 3: Metal- and catalyst-free preparation of pyrazole C-5-linked thioamide conjugates.
Scheme 4: Synthesis of 4-iodopyrazole C-3-tethered thioamides.
Scheme 5: Gram-scale scope of the current protocol.
Scheme 6: Control experiment.
Scheme 7: H2O2-mediated synthesis of pyrazole-pyridine conjugates with amide tethers.
Scheme 8: Synthesis of pyrazole-pyridine conjugates 9F and 10F having amide tethers.
Scheme 9: A tentative mechanism for the formation of pyrazole conjugates with thioamide and amide linkage.
Beilstein J. Org. Chem. 2023, 19, 115–132, doi:10.3762/bjoc.19.12
Graphical Abstract
Scheme 1: 1,3-Dithianes as useful synthetic building blocks: a) general synthetic utility (in Corey–Seebach-t...
Scheme 2: Metalation of other saturated heterocycles is often problematic due to β-elimination [16,17].
Scheme 3: Thianes as synthetic building blocks in the construction of complex molecules [18].
Figure 1: a) 1,4-Dithiane-type building blocks that can serve as C2-synthons and b) examples of complex targe...
Scheme 4: Synthetic availability of 1,4-dithiane-type building blocks.
Scheme 5: Dithiins and dihydrodithiins as pseudoaryl groups [36-39].
Scheme 6: Metalation of other saturated heterocycles is often problematic due to β-elimination [40-42].
Figure 2: Reactive conformations leading to β-fragmentation for lithiated 1,4-dithianes and 1,4-dithiin.
Scheme 7: Mild metalation of 1,4-dithiins affords stable heteroaryl-magnesium and heteroaryl-zinc-like reagen...
Scheme 8: Dithiin-based dienophiles and their use in synthesis [33,49-54].
Scheme 9: Dithiin-based dienes and their use in synthesis [55-57].
Scheme 10: Stereoselective 5,6-dihydro-1,4-dithiin-based synthesis of cis-olefins [42,58].
Scheme 11: Addition to aldehydes and applications in stereoselective synthesis.
Figure 3: Applications in the total synthesis of complex target products with original attachment place of 1,...
Scheme 12: Direct C–H functionalization methods for 1,4-dithianes [82,83].
Scheme 13: Known cycloaddition reactivity modes of allyl cations [84-100].
Scheme 14: Cycloadditions of 1,4-dithiane-fused allyl cations derived from dihydrodithiin-methanol 90 [101-107].
Scheme 15: Dearomative [3 + 2] cycloadditions of unprotected indoles with 1,4-dithiane-fused allyl alcohol 90 [30]....
Scheme 16: Comparison of reactivity of dithiin-fused allyl alcohols and similar non-cyclic sulfur-substituted ...
Scheme 17: Applications of dihydrodithiins in the rapid assembly of polycyclic terpenoid scaffolds [108,109].
Scheme 18: Dihydrodithiin-mediated allyl cation and vinyl carbene cycloadditions via a gold(I)-catalyzed 1,2-s...
Scheme 19: Activation mode of ethynyldithiolanes towards gold-coordinated 1,4-dithiane-fused allyl cation and ...
Scheme 20: Desulfurization problems.
Scheme 21: oxidative decoration strategies for 1,4-dithiane scaffolds.
Beilstein J. Org. Chem. 2023, 19, 66–77, doi:10.3762/bjoc.19.6
Graphical Abstract
Scheme 1: Examples of aza-Nazarov reactions.
Scheme 2: Aza-Nazarov cyclization on gram scale.
Scheme 3: Scope of the aza-Nazarov cyclization with acyclic imines. aThe syntheses of aza-Nazarov products 19b...
Figure 1: X-ray crystal structure of compound 19l.
Scheme 4: Proposed mechanism for the formation of diastereomers 19 and 22.
Scheme 5: Preparation of acyl chloride 23.
Scheme 6: Aza-Nazarov reaction tested using β-TMS-substituted acyl chloride 23.
Scheme 7: Hydrolysis of N-acyliminium intermediates.
Scheme 8: (a) Two possible pathways for the formation of 7 and (b) investigation of the reaction between imin...
Scheme 9: (a) Preparation of acyl chlorides 6ba and 6bb in diastereomerically pure forms, (b) aza-Nazarov cyc...
Beilstein J. Org. Chem. 2023, 19, 57–65, doi:10.3762/bjoc.19.5
Graphical Abstract
Figure 1: Representative natural products and biologically active molecules containing an oxindole moiety [7-13].
Scheme 1: Selected photocatalytic decarboxylative radical cascade reactions of N-arylamides.
Scheme 2: Arylamide substrate scope with isolated yields of products.
Scheme 3: Alkyl radical precursor scope with isolated yields of products.
Scheme 4: Selected mechanistic experiments.
Beilstein J. Org. Chem. 2023, 19, 1–26, doi:10.3762/bjoc.19.1
Graphical Abstract
Scheme 1: The power of radical retrosynthesis and the tactic of divergent total synthesis.
Figure 1: Evolution of radical chemistry for organic synthesis.
Scheme 2: Divergent total synthesis of α-pyrone-diterpenoids (Baran).
Scheme 3: Divergent synthesis of pyrone diterpenoids by merged chemoenzymatic and radical synthesis (part I, ...
Scheme 4: Divergent synthesis of pyrone diterpenoids by merged chemoenzymatic and radical synthesis (part II,...
Scheme 5: Divergent synthesis of drimane-type hydroquinone meroterpenoids (Li).
Scheme 6: Divergent synthesis of natural products isolated from Dysidea avara (Lu).
Scheme 7: Divergent synthesis of kaurene-type terpenoids (Lei).
Scheme 8: Divergent synthesis of 6-oxabicyclo[3.2.1]octane meroterpenoids (Lou).
Scheme 9: Divergent synthesis of crinipellins by radical-mediated Dowd–Backwith rearrangement (Xie and Ding).
Scheme 10: Divergent total synthesis of Galbulimima alkaloids (Shenvi).
Scheme 11: Divergent synthesis of eburnane alkaloids (Qin).
Scheme 12: Divergent synthesis of Aspidosperma alkaloids (Boger).
Scheme 13: Photoredox based synthesis of (−)-FR901483 (160) and (+)-TAN1251C (162, Gaunt).
Scheme 14: Divergent synthesis of bipolamines (Maimone).
Scheme 15: Flow chemistry divergency between aporphine and morphinandione alkaloids (Felpin).
Scheme 16: Divergent synthesis of pyrroloazocine natural products (Echavarren).
Scheme 17: Using TEMPO to stabilize radicals for the divergent synthesis of pyrroloindoline natural products (...
Scheme 18: Radical pathway for preparation of lignans (Zhu).
Scheme 19: Divergent synthesis of DBCOD lignans (Lumb).
Beilstein J. Org. Chem. 2022, 18, 1707–1719, doi:10.3762/bjoc.18.181
Graphical Abstract
Figure 1: General structure of grayanane natural products.
Scheme 1: Grayanane biosynthesis.
Scheme 2: Matsumoto’s relay approach.
Scheme 3: Shirahama’s total synthesis of (–)-grayanotoxin III.
Scheme 4: Newhouse’s syntheses of fragments 25 and 29.
Scheme 5: Newhouse’s total synthesis of principinol D.
Scheme 6: Ding’s total synthesis of rhodomolleins XX and XXII.
Scheme 7: First key step of Luo’s strategy.
Scheme 8: Luo’s total synthesis of grayanotoxin III.
Scheme 9: Synthesis of principinol E and rhodomollein XX.
Scheme 10: William’s synthetic effort towards pierisformaside C.
Scheme 11: Hong’s synthetic effort towards rhodojaponin III.
Scheme 12: Recent strategies for grayanane synthesis.
Beilstein J. Org. Chem. 2022, 18, 1672–1695, doi:10.3762/bjoc.18.179
Graphical Abstract
Scheme 1: Organocatalysis classification used in the present perspective.
Scheme 2: Oxidative processes catalyzed by amines.
Scheme 3: N-Heterocyclic carbene (NHC) catalysis in oxidative functionalization of aldehydes.
Scheme 4: Examples of asymmetric oxidative processes catalyzed by chiral Brønsted acids.
Scheme 5: Asymmetric aerobic α-hydroxylation of lactams under phase-transfer organocatalysis conditions emplo...
Scheme 6: Selective CH-oxidation of methylarenes to aldehydes or carboxylic acids.
Scheme 7: An example of the regioselective CH-amination by a sterically hindered imide-N-oxyl radical precurs...
Scheme 8: CH-amination of ethylbenzene and CH-fluorination of aldehydes catalyzed by N-hydroxybenzimidazoles,...
Scheme 9: Mixed hetero-/homogeneous TiO2/N-hydroxyimide photocatalysis in the selective benzylic oxidation.
Scheme 10: Electrochemical benzylic iodination and benzylation of pyridine by benzyl iodides generated in situ...
Scheme 11: Electrochemical oxidative C–O/C–N coupling of alkylarenes with NHPI. Electrolysis conditions: Const...
Scheme 12: Chemoselective alcohol oxidation catalyzed by TEMPO.
Scheme 13: ABNO-catalyzed oxidative C–N coupling of primary alcohols with primary amines.
Scheme 14: ACT-catalyzed electrochemical oxidation of primary alcohols and aldehydes to carboxylic acids.
Scheme 15: Electrocatalytic oxidation of benzylic alcohols by a TEMPO derivative immobilized on a graphite ano...
Scheme 16: Electrochemical oxidation of carbamates of cyclic amines to lactams and oxidative cyanation of amin...
Scheme 17: Hydrogen atom transfer (HAT) and single-electron transfer (SET) as basic principles of amine cation...
Scheme 18: Electrochemical quinuclidine-catalyzed oxidation involving unactivated C–H bonds.
Scheme 19: DABCO-mediated photocatalytic C–C cross-coupling involving aldehyde C–H bond cleavage.
Scheme 20: DABCO-derived cationic catalysts in inactivated C–H bond cleavage for alkyl radical addition to ele...
Scheme 21: Electrochemical diamination and dioxygenation of vinylarenes catalyzed by triarylamines.
Scheme 22: Electrochemical benzylic oxidation mediated by triarylimidazoles.
Scheme 23: Thiyl radical-catalyzed CH-arylation of allylic substrates by aryl cyanides.
Scheme 24: Synthesis of redox-active alkyl tetrafluoropyridinyl sulfides by unactivated C–H bond cleavage by t...
Scheme 25: Main intermediates in quinone oxidative organocatalysis.
Scheme 26: Electrochemical DDQ-catalyzed intramolecular dehydrogenative aryl–aryl coupling.
Scheme 27: DDQ-mediated cross-dehydrogenative C–N coupling of benzylic substrates with azoles.
Scheme 28: Biomimetic o-quinone-catalyzed benzylic alcohol oxidation.
Scheme 29: Electrochemical synthesis of secondary amines by oxidative coupling of primary amines and benzylic ...
Scheme 30: General scheme of dioxirane and oxaziridine oxidative organocatalysis.
Scheme 31: Dioxirane organocatalyzed CH-hydroxylation involving aliphatic C(sp3)–H bonds.
Scheme 32: Enantioselective hydroxylation of CH-acids catalyzed by chiral oxaziridines.
Scheme 33: Iodoarene-organocatalyzed vinylarene diamination.
Scheme 34: Iodoarene-organocatalyzed asymmetric CH-hydroxylation of benzylic substrates.
Scheme 35: Iodoarene-organocatalyzed asymmetric difluorination of alkenes with migration of aryl or methyl gro...
Scheme 36: Examples of 1,2-diiodo-4,5-dimethoxybenzene-catalyzed electrochemical oxidative heterocyclizations.
Scheme 37: Electrochemical N-ammonium ylide-catalyzed CH-oxidation.
Scheme 38: Oxidative dimerization of aryl- and alkenylmagnesium compounds catalyzed by quinonediimines.
Scheme 39: FLP-catalyzed dehydrogenation of N-substituted indolines.
Beilstein J. Org. Chem. 2022, 18, 1607–1616, doi:10.3762/bjoc.18.171
Graphical Abstract
Scheme 1: The diastereoselective synthesis of spirooxindoles through MCRs.
Figure 1: Bioactive Spirooxindole-pyrrolothiazoles.
Scheme 2: The synthesis of spirooxindolepyrrolothiazoles.
Scheme 3: Four-component reaction for the synthesis of compound 5.
Scheme 4: Proposed mechanism for the double [3 + 2] cycloadditions.
Scheme 5: The synthesis of compound 5a with ᴅ- and ʟ-cysteine.
Scheme 6: Two-step (process A) vs cascade (process B) synthesis of 5a. i) 1.0:1.15 of 1a/2, EtOH (0.05 M), 25...
Figure 2: Graphical representation of the green metrics (AE, AEf, CE, RME, OE and MP) analysis for processes ...
Figure 3: Graphical representation of the green metrics (PMI, E-factor, and SI) analysis for processes A and ...
Beilstein J. Org. Chem. 2022, 18, 1524–1531, doi:10.3762/bjoc.18.161
Graphical Abstract
Figure 1: Structures of RBV, betulinic acid (1), and ursolic acid (2).
Scheme 1: Synthesis of 1-azido-3-nitrobenzene (c).
Scheme 2: Synthesis of the triazole-substituted triterpene derivatives 7 and 8.
Figure 2: (A) Activity of compound 8 in A549 cells infected with RSV. MTT assay 96 h after treatment. DMSO (0...
Figure 3: Superposition of the top-ranked docking solution of compound 8 (carbon atoms in yellow, in stick re...
Beilstein J. Org. Chem. 2022, 18, 1479–1487, doi:10.3762/bjoc.18.155
Graphical Abstract
Scheme 1: Utilization of Ph3BiCl2 for organic reactions involving desulfurization.
Scheme 2: Synthesis of tafamidis (13).
Scheme 3: Control experiments.
Scheme 4: Proposed mechanism.