Search for "benzamide" in Full Text gives 81 result(s) in Beilstein Journal of Organic Chemistry.
Beilstein J. Org. Chem. 2021, 17, 819–865, doi:10.3762/bjoc.17.71
Graphical Abstract
Figure 1: Marketed drugs with acridine moiety.
Scheme 1: Synthesis of 4-arylacridinediones.
Scheme 2: Proposed mechanism for acridinedione synthesis.
Scheme 3: Synthesis of tetrahydrodibenzoacridinones.
Scheme 4: Synthesis of naphthoacridines.
Scheme 5: Plausible mechanism for naphthoacridines.
Figure 2: Benzoazepines based potent molecules.
Scheme 6: Synthesis of azepinone.
Scheme 7: Proposed mechanism for azepinone formation.
Scheme 8: Synthesis of benzoazulenen-1-one derivatives.
Scheme 9: Proposed mechanism for benzoazulene-1-one synthesis.
Figure 3: Indole-containing pharmacologically active molecules.
Scheme 10: Synthesis of functionalized indoles.
Scheme 11: Plausible mechanism for the synthesis of functionalized indoles.
Scheme 12: Synthesis of spirooxindoles.
Scheme 13: Synthesis of substituted spirooxindoles.
Scheme 14: Plausible mechanism for the synthesis of substituted spirooxindoles.
Scheme 15: Synthesis of pyrrolidinyl spirooxindoles.
Scheme 16: Proposed mechanism for pyrrolidinyl spirooxindoles.
Figure 4: Pyran-containing biologically active molecules.
Scheme 17: Synthesis of functionalized benzopyrans.
Scheme 18: Plausible mechanism for synthesis of benzopyran.
Scheme 19: Synthesis of indoline-spiro-fused pyran derivatives.
Scheme 20: Proposed mechanism for indoline-spiro-fused pyran.
Scheme 21: Synthesis of substituted naphthopyrans.
Figure 5: Marketed drugs with pyrrole ring.
Scheme 22: Synthesis of tetra-substituted pyrroles.
Scheme 23: Mechanism for silica-supported PPA-SiO2-catalyzed pyrrole synthesis.
Scheme 24: Synthesis of pyrrolo[1,10]-phenanthrolines.
Scheme 25: Proposed mechanism for pyrrolo[1,10]-phenanthrolines.
Figure 6: Marketed drugs and molecules containing pyrimidine and pyrimidinones skeletons.
Scheme 26: MWA-MCR pyrimidinone synthesis.
Scheme 27: Two proposed mechanisms for pyrimidinone synthesis.
Scheme 28: MWA multicomponent synthesis of dihydropyrimidinones.
Scheme 29: Proposed mechanism for dihydropyrimidinones.
Figure 7: Biologically active fused pyrimidines.
Scheme 30: MWA- MCR for the synthesis of pyrrolo[2,3-d]pyrimidines.
Scheme 31: Proposed mechanism for pyrrolo[2,3-d]pyrimidines.
Scheme 32: Synthesis of substituted pyrrolo[2,3-d]pyrimidine-2,4-diones.
Scheme 33: Probable pathway for pyrrolo[2,3-d]pyrimidine-2,4-diones.
Scheme 34: Synthesis of pyridopyrimidines.
Scheme 35: Plausible mechanism for the synthesis of pyridopyrimidines.
Scheme 36: Synthesis of dihydropyridopyrimidine and dihydropyrazolopyridine.
Scheme 37: Proposed mechanism for the formation of dihydropyridopyrimidine.
Scheme 38: Synthesis of thiopyrano[4,3-d]pyrimidines.
Scheme 39: Plausible mechanism for the synthesis of thiopyrano[4,3-d]pyrimidines.
Scheme 40: Synthesis of decorated imidazopyrimidines.
Scheme 41: Proposed mechanism for imidazopyrimidine synthesis.
Figure 8: Pharmacologically active molecules containing purine bases.
Scheme 42: Synthesis of aza-adenines.
Scheme 43: Synthesis of 5-aza-7-deazapurines.
Scheme 44: Proposed mechanism for deazapurines synthesis.
Figure 9: Biologically active molecules containing pyridine moiety.
Scheme 45: Synthesis of steroidal pyridines.
Scheme 46: Proposed mechanism for steroidal pyridine.
Scheme 47: Synthesis of N-alkylated 2-pyridones.
Scheme 48: Two possible mechanisms for pyridone synthesis.
Scheme 49: Synthesis of pyridone derivatives.
Scheme 50: Postulated mechanism for synthesis of pyridone.
Figure 10: Biologically active fused pyridines.
Scheme 51: Benzimidazole-imidazo[1,2-a]pyridines synthesis.
Scheme 52: Mechanism for the synthesis of benzimidazole-imidazo[1,2-a]pyridines.
Scheme 53: Synthesis of pyrazolo[3,4-b]pyridine-5-spirocycloalkanedione derivatives.
Scheme 54: Proposed mechanism for spiro-pyridines.
Scheme 55: Functionalized macrocyclane-fused pyrazolo[3,4-b]pyridine derivatives.
Scheme 56: Mechanism postulated for macrocyclane-fused pyrazolo[3,4-b]pyridine.
Scheme 57: Generation of pyrazolo[3,4-b]pyridines.
Scheme 58: Proposed mechanism for the synthesis of pyrazolo[3,4-b]pyridines.
Scheme 59: Proposed mechanism for the synthesis of azepinoindole.
Figure 11: Pharmaceutically important molecules with quinoline moiety.
Scheme 60: Povarov-mediated quinoline synthesis.
Scheme 61: Proposed mechanism for Povarov reaction.
Scheme 62: Synthesis of pyrazoloquinoline.
Scheme 63: Plausible mechanism for pyrazoloquinoline synthesis.
Figure 12: Quinazolinones as pharmacologically significant scaffolds.
Scheme 64: Four-component reaction for dihydroquinazolinone.
Scheme 65: Proposed mechanism for dihydroquinazolinones.
Scheme 66: Synthesis purine quinazolinone and PI3K-δ inhibitor.
Scheme 67: Synthesis of fused benzothiazolo/benzoimidazoloquinazolinones.
Scheme 68: Proposed mechanism for fused benzothiazolo/benzoimidazoloquinazolinones.
Scheme 69: On-water reaction for synthesis of thiazoloquinazolinone.
Scheme 70: Proposed mechanism for the thiazoloquinazolinone synthesis.
Scheme 71: β-Cyclodextrin-mediated synthesis of indoloquinazolinediones.
Scheme 72: Proposed mechanism for synthesis of indoloquinazolinediones.
Figure 13: Triazoles-containing marketted drugs and pharmacologically active molecules.
Scheme 73: Cu(I) DAPTA-catalyzed 1,2,3-triazole formation.
Scheme 74: Mechanism for Cu(I) DAPTA-catalyzed triazole formation.
Scheme 75: Synthesis of β-hydroxy-1,2,3-triazole.
Scheme 76: Proposed mechanism for synthesis of β-hydroxy-1,2,3-triazoles.
Scheme 77: Synthesis of bis-1,2,4-triazoles.
Scheme 78: Proposed mechanism for bis-1,2,4-triazoles synthesis.
Figure 14: Thiazole containing drugs.
Scheme 79: Synthesis of a substituted thiazole ring.
Scheme 80: Synthesis of pyrazolothiazoles.
Figure 15: Chromene containing drugs.
Scheme 81: Magnetic nanocatalyst-mediated aminochromene synthesis.
Scheme 82: Proposed mechanism for the synthesis of chromenes.
Beilstein J. Org. Chem. 2020, 16, 2151–2192, doi:10.3762/bjoc.16.183
Graphical Abstract
Figure 1: Fluorine-containing drugs.
Figure 2: Fluorinated agrochemicals.
Scheme 1: Selectivity of fluorination reactions.
Scheme 2: Different mechanisms of photocatalytic activation. Sub = substrate.
Figure 3: Jablonski diagram showing visible-light-induced energy transfer pathways: a) absorption, b) IC, c) ...
Figure 4: Schematic illustration of TTET.
Figure 5: Organic triplet PSCats.
Figure 6: Additional organic triplet PSCats.
Figure 7: A) Further organic triplet PSCats and B) transition metal triplet PSCats.
Figure 8: Different fluorination reagents grouped by generation.
Scheme 3: Synthesis of Selectfluor®.
Scheme 4: General mechanism of PS TTET C(sp3)–H fluorination.
Scheme 5: Selective benzylic mono- and difluorination using 9-fluorenone and xanthone PSCats, respectively.
Scheme 6: Chen’s photosensitized monofluorination: reaction scope.
Scheme 7: Chen’s photosensitized benzylic difluorination reaction scope.
Scheme 8: Photosensitized monofluorination of ethylbenzene on a gram scale.
Scheme 9: Substrate scope of Tan’s AQN-photosensitized C(sp3)–H fluorination.
Scheme 10: AQN-photosensitized C–H fluorination reaction on a gram scale.
Scheme 11: Reaction mechanism of the AQN-assisted fluorination.
Figure 9: 3D structures of the singlet ground and triplet excited states of Selectfluor®.
Scheme 12: Associated transitions for the activation of acetophenone by violet light.
Scheme 13: Ethylbenzene C–H fluorination with various PSCats and conditions.
Scheme 14: Effect of different PSCats on the C(sp3)–H fluorination of cyclohexane (39).
Scheme 15: Reaction scope of Chen’s acetophenone-photosensitized C(sp3)–H fluorination reaction.
Figure 10: a) Site-selectivity of Chen’s acetophenone-photosensitized C–H fluorination reaction [201]. b) Site-sele...
Scheme 16: Formation of the AQN–Selectfluor® exciplex Int1.
Scheme 17: Generation of the C3 2° pentane radical and the Selectfluor® N-radical cation from the exciplex.
Scheme 18: Hydrogen atom abstraction by the Selectfluor® N-radical cation from pentane to give the C3 2° penta...
Scheme 19: Fluorine atom transfer from Selectfluor® to the C3 2° pentane radical to yield 3-fluoropentane and ...
Scheme 20: Barrierless fluorine atom transfer from Int1 to the C3 2° pentane radical to yield 3-fluoropentane,...
Scheme 21: Ketone-directed C(sp3)–H fluorination.
Scheme 22: Ketone-directed fluorination through a 5- and a 6-membered transition state, respectively.
Scheme 23: Effect of different PSCats on the photosensitized C(sp3)–H fluorination of 47.
Scheme 24: Substrate scope of benzil-photoassisted C(sp3)–H fluorinations.
Scheme 25: A) Benzil-photoassisted enone-directed C(sp3)–H fluorination. B) Classification of the reaction mod...
Scheme 26: A) Xanthone-photoassisted ketal-directed C(sp3)–H fluorination. B) Substrate scope. C) C–H fluorina...
Scheme 27: Rationale for the selective HAT at the C2 C–H bond of galactose acetonide.
Scheme 28: Photosensitized C(sp3)–H benzylic fluorination of a peptide using different PSCats.
Scheme 29: Peptide scope of 5-benzosuberenone-photoassisted C(sp3)–H fluorinations.
Scheme 30: Continuous flow PS TTET monofluorination of 72.
Scheme 31: Photosensitized C–H fluorination of N-butylphthalimide as a PSX.
Scheme 32: Substrate scope and limitations of the PSX C(sp3)–H monofluorination.
Scheme 33: Substrate crossover monofluorination experiment.
Scheme 34: PS TTET mechanism proposed by Hamashima and co-workers.
Scheme 35: Photosensitized TFM of 78 to afford α-trifluoromethylated ketone 80.
Scheme 36: Substrate scope for photosensitized styrene TFM to give α-trifluoromethylated ketones.
Scheme 37: Control reactions for photosensitized TFM of styrenes.
Scheme 38: Reaction mechanism for photosensitized TFM of styrenes to afford α-trifluoromethylated ketones.
Scheme 39: Reaction conditions for TFMs to yield the cis- and the trans-product, respectively.
Scheme 40: Substrate scope of trifluoromethylated (E)-styrenes.
Scheme 41: Strategies toward trifluoromethylated (Z)-styrenes.
Scheme 42: Substrate scope of trifluoromethylated (Z)-styrenes.
Scheme 43: Reaction mechanism for photosensitized TFM of styrenes to afford E- or Z-products.
Beilstein J. Org. Chem. 2020, 16, 1754–1804, doi:10.3762/bjoc.16.147
Graphical Abstract
Figure 1: Concept of dual synergistic catalysis.
Figure 2: Classification of catalytic systems involving two catalysts.
Figure 3: General mechanism for the dual nickel/photoredox catalytic system.
Figure 4: General mechanisms for C–H activation catalysis involving different reoxidation strategies.
Figure 5: Indole synthesis via dual C–H activation/photoredox catalysis.
Figure 6: Proposed mechanism for the indole synthesis via dual catalysis.
Figure 7: Oxidative Heck reaction on arenes via the dual catalysis.
Figure 8: Proposed mechanism for the Heck reaction on arenes via dual catalysis.
Figure 9: Oxidative Heck reaction on phenols via the dual catalysis.
Figure 10: Proposed mechanism for the Heck reaction on phenols via dual catalysis.
Figure 11: Carbazole synthesis via dual C–H activation/photoredox catalysis.
Figure 12: Proposed mechanism for the carbazole synthesis via dual catalysis.
Figure 13: Carbonylation of enamides via the dual C–H activation/photoredox catalysis.
Figure 14: Proposed mechanism for carbonylation of enamides via dual catalysis.
Figure 15: Annulation of benzamides via the dual C–H activation/photoredox catalysis.
Figure 16: Proposed mechanism for the annulation of benzamides via dual catalysis.
Figure 17: Synthesis of indoles via the dual C–H activation/photoredox catalysis.
Figure 18: Proposed mechanism for the indole synthesis via dual catalysis.
Figure 19: General concept of dual catalysis merging C–H activation and photoredox catalysis.
Figure 20: The first example of dual catalysis merging C–H activation and photoredox catalysis.
Figure 21: Proposed mechanism for the C–H arylation with diazonium salts via dual catalysis.
Figure 22: Dual catalysis merging C–H activation/photoredox using diaryliodonium salts.
Figure 23: Direct arylation via the dual catalytic system reported by Xu.
Figure 24: Direct arylation via dual catalytic system reported by Balaraman.
Figure 25: Direct arylation via dual catalytic system reported by Guo.
Figure 26: C(sp3)–H bond arylation via the dual Pd/photoredox catalytic system.
Figure 27: Acetanilide derivatives acylation via the dual C–H activation/photoredox catalysis.
Figure 28: Proposed mechanism for the C–H acylation with α-ketoacids via dual catalysis.
Figure 29: Acylation of azobenzenes via the dual catalysis C–H activation/photoredox.
Figure 30: C2-acylation of indoles via the dual C–H activation/photoredox catalysis.
Figure 31: Proposed mechanism for the C2-acylation of indoles with aldehydes via dual catalysis.
Figure 32: C2-acylation of indoles via the dual C–H activation/photoredox catalysis.
Figure 33: Perfluoroalkylation of arenes via the dual C–H activation/photoredox catalysis.
Figure 34: Proposed mechanism for perfluoroalkylation of arenes via dual catalysis.
Figure 35: Sulfonylation of 1-naphthylamides via the dual C–H activation/photoredox catalysis.
Figure 36: Proposed mechanism for sulfonylation of 1-naphthylamides via dual catalysis.
Figure 37: meta-C–H Alkylation of arenes via visible-light metallaphotocatalysis.
Figure 38: Alternative procedure for meta-C–H alkylation of arenes via metallaphotocatalysis.
Figure 39: Proposed mechanism for meta-C–H alkylation of arenes via metallaphotocatalysis.
Figure 40: C–H borylation of arenes via visible-light metallaphotocatalysis.
Figure 41: Proposed mechanism for C–H borylation of arenes via visible-light metallaphotocatalysis.
Figure 42: Undirected C–H aryl–aryl cross coupling via dual gold/photoredox catalysis.
Figure 43: Proposed mechanism for the undirected C–H aryl–aryl cross-coupling via dual catalysis.
Figure 44: Undirected C–H arylation of (hetero)arenes via dual manganese/photoredox catalysis.
Figure 45: Proposed mechanism for the undirected arylation of (hetero)arenes via dual catalysis.
Figure 46: Photoinduced C–H arylation of azoles via copper catalysis.
Figure 47: Photo-induced C–H chalcogenation of azoles via copper catalysis.
Figure 48: Decarboxylative C–H adamantylation of azoles via dual cobalt/photoredox catalysis.
Figure 49: Proposed mechanism for the C–H adamantylation of azoles via dual catalysis.
Figure 50: General mechanisms for the “classical” (left) and Cu-free variant (right) Sonogoshira reaction.
Figure 51: First example of a dual palladium/photoredox catalysis for Sonogashira-type couplings.
Figure 52: Arylation of terminal alkynes with diazonium salts via dual gold/photoredox catalysis.
Figure 53: Proposed mechanism for the arylation of terminal alkynes via dual catalysis.
Figure 54: C–H Alkylation of alcohols promoted by H-atom transfer (HAT).
Figure 55: Proposed mechanism for the C–H alkylation of alcohols promoted by HAT.
Figure 56: C(sp3)–H arylation of latent nucleophiles promoted by H-atom transfer.
Figure 57: Proposed mechanism for the C(sp3)–H arylation of latent nucleophiles promoted by HAT.
Figure 58: Direct α-arylation of alcohols promoted by H-atom transfer.
Figure 59: Proposed mechanism for the direct α-arylation of alcohols promoted by HAT.
Figure 60: C–H arylation of amines via dual Ni/photoredox catalysis.
Figure 61: Proposed mechanism for the C–H arylation of amines via dual Ni/photoredox catalysis.
Figure 62: C–H functionalization of nucleophiles via excited ketone/nickel dual catalysis.
Figure 63: Proposed mechanism for the C–H functionalization enabled by excited ketones.
Figure 64: Selective sp3–sp3 cross-coupling promoted by H-atom transfer.
Figure 65: Proposed mechanism for the selective sp3–sp3 cross-coupling promoted by HAT.
Figure 66: Direct C(sp3)–H acylation of amines via dual Ni/photoredox catalysis.
Figure 67: Proposed mechanism for the C–H acylation of amines via dual Ni/photoredox catalysis.
Figure 68: C–H hydroalkylation of internal alkynes via dual Ni/photoredox catalysis.
Figure 69: Proposed mechanism for the C–H hydroalkylation of internal alkynes.
Figure 70: Alternative procedure for the C–H hydroalkylation of ynones, ynoates, and ynamides.
Figure 71: Allylic C(sp3)–H activation via dual Ni/photoredox catalysis.
Figure 72: Proposed mechanism for the allylic C(sp3)–H activation via dual Ni/photoredox catalysis.
Figure 73: Asymmetric allylation of aldehydes via dual Cr/photoredox catalysis.
Figure 74: Proposed mechanism for the asymmetric allylation of aldehydes via dual catalysis.
Figure 75: Aldehyde C–H functionalization promoted by H-atom transfer.
Figure 76: Proposed mechanism for the C–H functionalization of aldehydes promoted by HAT.
Figure 77: Direct C–H arylation of strong aliphatic bonds promoted by HAT.
Figure 78: Proposed mechanism for the C–H arylation of strong aliphatic bonds promoted by HAT.
Figure 79: Direct C–H trifluoromethylation of strong aliphatic bonds promoted by HAT.
Figure 80: Proposed mechanism for the C–H trifluoromethylation of strong aliphatic bonds.
Beilstein J. Org. Chem. 2019, 15, 1907–1912, doi:10.3762/bjoc.15.186
Graphical Abstract
Figure 1: Representative sulfonyl fluoride compounds applied in medicinal chemistry and chemical biology.
Scheme 1: Synthesis background of N-fluorosulfonyl amides and fluorosulfates.
Scheme 2: Screening of the substrate scope of amides. Reaction conditions: a mixture of amides 1 (1.0 mmol), ...
Scheme 3: Amide resonance model and X-ray single crystal structure of 4e (CCDC 1906002).
Scheme 4: The proposed reaction mechanism.
Beilstein J. Org. Chem. 2019, 15, 1864–1871, doi:10.3762/bjoc.15.182
Graphical Abstract
Scheme 1: Comparison of our work with previous studies.
Scheme 2: Scope of pyridinium salts and benzylamine substrates. Reaction conditions: 1 (1 mmol), 2 (1 mmol), ...
Scheme 3: Scope of pyridinium salts and benzyl alcohol substrates. Reaction conditions: 1 (1 mmol), 4 (1 mmol...
Scheme 4: Scope of pyridinium salts, primary and secondary amine substrates. Reaction conditions: 1 (1 mmol), ...
Scheme 5: Control experiments for the oxidative cleavage of C–C bonds.
Scheme 6: Plausible reaction mechanism for the synthesis of N-alkylated benzamides 3.
Beilstein J. Org. Chem. 2019, 15, 1612–1704, doi:10.3762/bjoc.15.165
Graphical Abstract
Figure 1: Various drugs having IP nucleus.
Figure 2: Participation percentage of various TMs for the syntheses of IPs.
Scheme 1: CuI–NaHSO4·SiO2-catalyzed synthesis of imidazo[1,2-a]pyridines.
Scheme 2: Experimental examination of reaction conditions.
Scheme 3: One-pot tandem reaction for the synthesis of 2-haloimidazopyridines.
Scheme 4: Mechanistic scheme for the synthesis of 2-haloimidazopyridine.
Scheme 5: Copper-MOF-catalyzed three-component reaction (3-CR) for imidazo[1,2-a]pyridines.
Scheme 6: Mechanism for copper-MOF-driven synthesis.
Scheme 7: Heterogeneous synthesis via titania-supported CuCl2.
Scheme 8: Mechanism involving oxidative C–H functionalization.
Scheme 9: Heterogeneous synthesis of IPs.
Scheme 10: One-pot regiospecific synthesis of imidazo[1,2-a]pyridines.
Scheme 11: Vinyl azide as an unprecedented substrate for imidazo[1,2-a]pyridines.
Scheme 12: Radical pathway.
Scheme 13: Cu(I)-catalyzed transannulation approach for imidazo[1,5-a]pyridines.
Scheme 14: Plausible radical pathway for the synthesis of imidazo[1,5-a]pyridines.
Scheme 15: A solvent-free domino reaction for imidazo[1,2-a]pyridines.
Scheme 16: Cu-NPs-mediated synthesis of imidazo[1,2-a]pyridines.
Scheme 17: CuI-catalyzed synthesis of isoxazolylimidazo[1,2-a]pyridines.
Scheme 18: Functionalization of 4-bromo derivative via Sonogashira coupling reaction.
Scheme 19: A plausible reaction pathway.
Scheme 20: Cu(I)-catalyzed intramolecular oxidative C–H amidation reaction.
Scheme 21: One-pot synthetic reaction for imidazo[1,2-a]pyridine.
Scheme 22: Plausible reaction mechanism.
Scheme 23: Cu(OAc)2-promoted synthesis of imidazo[1,2-a]pyridines.
Scheme 24: Mechanism for aminomethylation/cycloisomerization of propiolates with imines.
Scheme 25: Three-component synthesis of imidazo[1,2-a]pyridines.
Figure 3: Scope of pyridin-2(1H)-ones and acetophenones.
Scheme 26: CuO NPS-promoted A3 coupling reaction.
Scheme 27: Cu(II)-catalyzed C–N bond formation reaction.
Scheme 28: Mechanism involving Chan–Lam/Ullmann coupling.
Scheme 29: Synthesis of formyl-substituted imidazo[1,2-a]pyridines.
Scheme 30: A tandem sp3 C–H amination reaction.
Scheme 31: Probable mechanistic approach.
Scheme 32: Dual catalytic system for imidazo[1,2-a]pyridines.
Scheme 33: Tentative mechanism.
Scheme 34: CuO/CuAl2O4/ᴅ-glucose-promoted 3-CCR.
Scheme 35: A tandem CuOx/OMS-2-based synthetic strategy.
Figure 4: Biomimetic catalytic oxidation in the presence of electron-transfer mediators (ETMs).
Scheme 36: Control experiment.
Scheme 37: Copper-catalyzed C(sp3)–H aminatin reaction.
Scheme 38: Reaction of secondary amines.
Scheme 39: Probable mechanistic pathway.
Scheme 40: Coupling reaction of α-azidoketones.
Scheme 41: Probable pathway.
Scheme 42: Probable mechanism with free energy calculations.
Scheme 43: MCR for cyanated IP synthesis.
Scheme 44: Substrate scope for the reaction.
Scheme 45: Reaction mechanism.
Scheme 46: Probable mechanistic pathway for Cu/ZnAl2O4-catalyzed reaction.
Scheme 47: Copper-catalyzed double oxidative C–H amination reaction.
Scheme 48: Application towards different coupling reactions.
Scheme 49: Reaction mechanism.
Scheme 50: Condensation–cyclization approach for the synthesis of 1,3-diarylated imidazo[1,5-a]pyridines.
Scheme 51: Optimized reaction conditions.
Scheme 52: One-pot 2-CR.
Scheme 53: One-pot 3-CR without the isolation of chalcone.
Scheme 54: Copper–Pybox-catalyzed cyclization reaction.
Scheme 55: Mechanistic pathway catalyzed by Cu–Pybox complex.
Scheme 56: Cu(II)-promoted C(sp3)-H amination reaction.
Scheme 57: Wider substrate applicability for the reaction.
Scheme 58: Plausible reaction mechanism.
Scheme 59: CuI assisted C–N cross-coupling reaction.
Scheme 60: Probable reaction mechanism involving sp3 C–H amination.
Scheme 61: One-pot MCR-catalyzed by CoFe2O4/CNT-Cu.
Scheme 62: Mechanistic pathway.
Scheme 63: Synthetic scheme for 3-nitroimidazo[1,2-a]pyridines.
Scheme 64: Plausible mechanism for CuBr-catalyzed reaction.
Scheme 65: Regioselective synthesis of halo-substituted imidazo[1,2-a]pyridines.
Scheme 66: Synthesis of 2-phenylimidazo[1,2-a]pyridines.
Scheme 67: Synthesis of diarylated compounds.
Scheme 68: CuBr2-mediated one-pot two-component oxidative coupling reaction.
Scheme 69: Decarboxylative cyclization route to synthesize 1,3-diarylimidazo[1,5-a]pyridines.
Scheme 70: Mechanistic pathway.
Scheme 71: C–H functionalization reaction of enamines to produce diversified heterocycles.
Scheme 72: A plausible mechanism.
Scheme 73: CuI-promoted aerobic oxidative cyclization reaction of ketoxime acetates and pyridines.
Scheme 74: CuI-catalyzed pathway for the formation of imidazo[1,2-a]pyridine.
Scheme 75: Mechanistic pathway.
Scheme 76: Mechanistic rationale for the synthesis of products.
Scheme 77: Copper-catalyzed synthesis of vinyloxy-IP.
Scheme 78: Regioselective product formation with propiolates.
Scheme 79: Proposed mechanism for vinyloxy-IP formation.
Scheme 80: Regioselective synthesis of 3-hetero-substituted imidazo[1,2-a]pyridines with different reaction su...
Scheme 81: Mechanistic pathway.
Scheme 82: CuI-mediated synthesis of 3-formylimidazo[1,2-a]pyridines.
Scheme 83: Radical pathway for 3-formylated IP synthesis.
Scheme 84: Pd-catalyzed urea-cyclization reaction for IPs.
Scheme 85: Pd-catalyzed one-pot-tandem amination and intramolecular amidation reaction.
Figure 5: Scope of aniline nucleophiles.
Scheme 86: Pd–Cu-catalyzed Sonogashira coupling reaction.
Scheme 87: One-pot amide coupling reaction for the synthesis of imidazo[4,5-b]pyridines.
Scheme 88: Urea cyclization reaction for the synthesis of two series of pyridines.
Scheme 89: Amidation reaction for the synthesis of imidazo[4,5-b]pyridines.
Figure 6: Amide scope.
Scheme 90: Pd NPs-catalyzed 3-component reaction for the synthesis of 2,3-diarylated IPs.
Scheme 91: Plausible mechanistic pathway for Pd NPs-catalyzed MCR.
Scheme 92: Synthesis of chromenoannulated imidazo[1,2-a]pyridines.
Scheme 93: Mechanism for the synthesis of chromeno-annulated IPs.
Scheme 94: Zinc oxide NRs-catalyzed synthesis of imidazo[1,2-a]azines/diazines.
Scheme 95: Zinc oxide-catalyzed isocyanide based GBB reaction.
Scheme 96: Reaction pathway for ZnO-catalyzed GBB reaction.
Scheme 97: Mechanistic pathway.
Scheme 98: ZnO NRs-catalyzed MCR for the synthesis of imidazo[1,2-a]azines.
Scheme 99: Ugi type GBB three-component reaction.
Scheme 100: Magnetic NPs-catalyzed synthesis of imidazo[1,2-a]pyridines.
Scheme 101: Regioselective synthesis of 2-alkoxyimidazo[1,2-a]pyridines catalyzed by Fe-SBA-15.
Scheme 102: Plausible mechanistic pathway for the synthesis of 2-alkoxyimidazopyridine.
Scheme 103: Iron-catalyzed synthetic approach.
Scheme 104: Iron-catalyzed aminooxygenation reaction.
Scheme 105: Mechanistic pathway.
Scheme 106: Rh(III)-catalyzed double C–H activation of 2-substituted imidazoles and alkynes.
Scheme 107: Plausible reaction mechanism.
Scheme 108: Rh(III)-catalyzed non-aromatic C(sp2)–H bond activation–functionalization for the synthesis of imid...
Scheme 109: Reactivity and selectivity of different substrates.
Scheme 110: Rh-catalyzed direct C–H alkynylation by Li et al.
Scheme 111: Suggested radical mechanism.
Scheme 112: Scandium(III)triflate-catalyzed one-pot reaction and its mechanism for the synthesis of benzimidazo...
Scheme 113: RuCl3-assisted Ugi-type Groebke–Blackburn condensation reaction.
Scheme 114: C-3 aroylation via Ru-catalyzed two-component reaction.
Scheme 115: Regioselective synthetic mechanism.
Scheme 116: La(III)-catalyzed one-pot GBB reaction.
Scheme 117: Mechanistic approach for the synthesis of imidazo[1,2-a]pyridines.
Scheme 118: Synthesis of imidazo[1,2-a]pyridine using LaMnO3 NPs under neat conditions.
Scheme 119: Mechanistic approach.
Scheme 120: One-pot 3-CR for regioselective synthesis of 2-alkoxy-3-arylimidazo[1,2-a]pyridines.
Scheme 121: Formation of two possible products under optimization of the catalysts.
Scheme 122: Mechanistic strategy for NiFe2O4-catalyzed reaction.
Scheme 123: Two-component reaction for synthesizing imidazodipyridiniums.
Scheme 124: Mechanistic scheme for the synthesis of imidazodipyridiniums.
Scheme 125: CuI-catalyzed arylation of imidazo[1,2-a]pyridines.
Scheme 126: Mechanism for arylation reaction.
Scheme 127: Cupric acetate-catalyzed double carbonylation approach.
Scheme 128: Radical mechanism for double carbonylation of IP.
Scheme 129: C–S bond formation reaction catalyzed by cupric acetate.
Scheme 130: Cupric acetate-catalyzed C-3 formylation approach.
Scheme 131: Control experiments for signifying the role of DMSO and oxygen.
Scheme 132: Mechanism pathway.
Scheme 133: Copper bromide-catalyzed CDC reaction.
Scheme 134: Extension of the substrate scope.
Scheme 135: Plausible radical pathway.
Scheme 136: Transannulation reaction for the synthesis of imidazo[1,5-a]pyridines.
Scheme 137: Plausible reaction pathway for denitrogenative transannulation.
Scheme 138: Cupric acetate-catalyzed C-3 carbonylation reaction.
Scheme 139: Plausible mechanism for regioselective C-3 carbonylation.
Scheme 140: Alkynylation reaction at C-2 of 3H-imidazo[4,5-b]pyridines.
Scheme 141: Two-way mechanism for C-2 alkynylation of 3H-imidazo[4,5-b]pyridines.
Scheme 142: Palladium-catalyzed SCCR approach.
Scheme 143: Palladium-catalyzed Suzuki coupling reaction.
Scheme 144: Reaction mechanism.
Scheme 145: A phosphine free palladium-catalyzed synthesis of C-3 arylated imidazopyridines.
Scheme 146: Palladium-mediated Buchwald–Hartwig cross-coupling reaction.
Figure 7: Structure of the ligands optimized.
Scheme 147: Palladium acetate-catalyzed direct arylation of imidazo[1,2-a]pyridines.
Scheme 148: Palladium acetate-catalyzed mechanistic pathway.
Scheme 149: Palladium acetate-catalyzed regioselective arylation reported by Liu and Zhan.
Scheme 150: Mechanism for selective C-3 arylation of IP.
Scheme 151: Pd(II)-catalyzed alkenylation reaction with styrenes.
Scheme 152: Pd(II)-catalyzed alkenylation reaction with acrylates.
Scheme 153: A two way mechanism.
Scheme 154: Double C–H activation reaction catalyzed by Pd(OAc)2.
Scheme 155: Probable mechanism.
Scheme 156: Palladium-catalyzed decarboxylative coupling.
Scheme 157: Mechanistic cycle for decarboxylative arylation reaction.
Scheme 158: Ligand-free approach for arylation of imidazo[1,2-a]pyridine-3-carboxylic acids.
Scheme 159: Mechanism for ligandless arylation reaction.
Scheme 160: NHC-Pd(II) complex assisted arylation reaction.
Scheme 161: C-3 arylation of imidazo[1,2-a]pyridines with aryl bromides catalyzed by Pd(OAc)2.
Scheme 162: Pd(II)-catalyzed C-3 arylations with aryl tosylates and mesylates.
Scheme 163: CDC reaction for the synthesis of imidazo[1,2-a]pyridines.
Scheme 164: Plausible reaction mechanism for Pd(OAc)2-catalyzed synthesis of imidazo[1,2-a]pyridines.
Scheme 165: Pd-catalyzed C–H amination reaction.
Scheme 166: Mechanism for C–H amination reaction.
Scheme 167: One-pot synthesis for 3,6-di- or 2,3,6-tri(hetero)arylimidazo[1,2-a]pyridines.
Scheme 168: C–H/C–H cross-coupling reaction of IPs and azoles catalyzed by Pd(II).
Scheme 169: Mechanistic cycle.
Scheme 170: Rh-catalyzed C–H arylation reaction.
Scheme 171: Mechanistic pathway for C–H arylation of imidazo[1,2-a]pyridine.
Scheme 172: Rh(III)-catalyzed double C–H activation of 2-phenylimidazo[1,2-a]pyridines and alkynes.
Scheme 173: Rh(III)-catalyzed mechanistic pathway.
Scheme 174: Rh(III)-mediated oxidative coupling reaction.
Scheme 175: Reactions showing functionalization of the product obtained by the group of Kotla.
Scheme 176: Mechanism for Rh(III)-catalyzed oxidative coupling reaction.
Scheme 177: Rh(III)-catalyzed C–H activation reaction.
Scheme 178: Mechanistic cycle.
Scheme 179: Annulation reactions of 2-arylimidazo[1,2-a]pyridines and alkynes.
Scheme 180: Two-way reaction mechanism for annulations reaction.
Scheme 181: [RuCl2(p-cymene)]2-catalyzed C–C bond formation reaction.
Scheme 182: Reported reaction mechanism.
Scheme 183: Fe(III) catalyzed C-3 formylation approach.
Scheme 184: SET mechanism-catalyzed by Fe(III).
Scheme 185: Ni(dpp)Cl2-catalyzed KTC coupling.
Scheme 186: Pd-catalyzed SM coupling.
Scheme 187: Vanadium-catalyzed coupling of IP and NMO.
Scheme 188: Mechanistic cycle.
Scheme 189: Selective C3/C5–H bond functionalizations by mono and bimetallic systems.
Scheme 190: rGO-Ni@Pd-catalyzed C–H bond arylation of imidazo[1,2-a]pyridine.
Scheme 191: Mechanistic pathway for heterogeneously catalyzed arylation reaction.
Scheme 192: Zinc triflate-catalyzed coupling reaction of substituted propargyl alcohols.
Beilstein J. Org. Chem. 2019, 15, 1065–1085, doi:10.3762/bjoc.15.104
Graphical Abstract
Figure 1: γ-Lactam-derived structures considered in this review.
Figure 2: Alkaloids containing an isoindolinone moiety.
Figure 3: Alkaloids containing the 2-oxindole ring system.
Figure 4: Drugs and biological active compounds containing an isoindolinone moiety.
Figure 5: Drugs and biologically active compounds bearing a 2-oxindole skeleton.
Scheme 1: Three-component reaction of benzoic acid 1, amides 2 and DMSO (3).
Scheme 2: Copper-catalysed three-component reaction of 2-iodobenzoic acids 10, alkynylcarboxylic acids 11 and...
Scheme 3: Proposed mechanism for the formation of methylene isoindolinones 13.
Scheme 4: Copper-catalysed three-component reaction of 2-iodobenzamide 17, terminal alkyne 18 and pyrrole or ...
Scheme 5: Palladium-catalysed three-component reaction of ethynylbenzamides 21, secondary amines 22 and CO (23...
Scheme 6: Proposed mechanism for the formation of methyleneisoindolinones 24.
Scheme 7: Copper-catalysed three-component reaction of formyl benzoate 29, amines 2 and alkynes 18.
Scheme 8: Copper-catalysed three-component reaction of formylbenzoate 29, amines 2 and ketones 31.
Scheme 9: Non-catalysed (A) and phase-transfer catalysed (B) three-component reactions of formylbenzoic acids ...
Scheme 10: Proposed mechanism for the formation of isoindolinones 36.
Scheme 11: Three-component reaction of formylbenzoic acid 33, amines 2 and fluorinated silyl ethers 39.
Scheme 12: Three-component Ugi reaction of 2-formylbenzoic acid (33), diamines 41 and isocyanides 42.
Scheme 13: Non-catalysed (A, B) and chiral phosphoric acid promoted (C) three-component Ugi reactions of formy...
Scheme 14: Proposed mechanism for the enantioselective formation of isoindolinones 46.
Scheme 15: Three-component reaction of benzoic acids 33 or 54, amines 2 and TMSCN (52).
Scheme 16: Several variations of the three-component reaction of formylbenzoic acids 33, amines 2 and isatoic ...
Scheme 17: Proposed mechanism for the synthesis of isoindoloquinazolinones 57.
Scheme 18: Three-component reaction of isobenzofuranone 61, amines 2 and isatoic anhydrides 56.
Scheme 19: Palladium-catalysed three-component reaction of 2-aminobenzamides 59, 2-bromobenzaldehydes 62 and C...
Scheme 20: Proposed mechanism for the palladium-catalysed synthesis of isoindoloquinazolinones 57.
Scheme 21: Four-component reaction of 2-vinylbenzoic acids 67, aryldioazonium tetrafluoroborates 68, DABCO·(SO2...
Scheme 22: Plausible mechanism for the formation of isoindolinones 71.
Scheme 23: Three-component reaction of trimethylsilylaryltriflates 77, isocyanides 42 and CO2 (78).
Scheme 24: Plausible mechanism for the three-component synthesis of phthalimides 79.
Scheme 25: Copper-catalysed three-component reaction of 2-formylbenzonitriles 85, arenes 86 and diaryliodonium...
Scheme 26: Copper-catalysed three-component reaction of 2-formylbenzonitriles 85, diaryliodonium salts 87 and ...
Scheme 27: Proposed mechanism for the formation of 2,3-diarylisoindolinones 88, 89 and 92.
Scheme 28: Palladium-catalysed three-component reaction of chloroquinolinecarbaldehydes 97 with isocyanides 42...
Scheme 29: Palladium-catalysed three-component reaction of imines 99 with CO (23) and ortho-iodoarylimines 100....
Scheme 30: Palladium-catalysed three-component reaction of amines 2 with CO (23) and aryl iodide 105.
Scheme 31: Three-component reaction of 2-ethynylanilines 109, perfluoroalkyl iodides 110 and carbon monoxide (...
Scheme 32: Ultraviolet-induced three-component reaction of N-(2-iodoaryl)acrylamides 113, DABCO·(SO2)2 (69) an...
Scheme 33: Proposed mechanism for the preparation of oxindoles 115.
Scheme 34: Three-component reaction of acrylamide 113, CO (23) and 1,4-benzodiazepine 121.
Scheme 35: Multicomponent reaction of sulfonylacrylamides 123, aryldiazonium tetrafluoroborates 68 and DABCO·(...
Scheme 36: Proposed mechanism for the preparation of oxindoles 124.
Scheme 37: Three-component reaction of N-arylpropiolamides 128, aryl iodides 129 and boronic acids 130.
Scheme 38: Proposed mechanism for the formation of diarylmethylene- and diarylallylideneoxindoles 131 and 132.
Scheme 39: Three-component reaction of cyclohexa-1,3-dione (136), amines 2 and alkyl acetylenedicarboxylates 1...
Scheme 40: Proposed mechanism for the formation of 2-oxindoles 138.
Beilstein J. Org. Chem. 2018, 14, 2822–2828, doi:10.3762/bjoc.14.260
Graphical Abstract
Figure 1: Structures of hamamelitannin (1), lead compound 2 and target compounds 3.
Scheme 1: Proposed strategy for the synthesis of the target analogues.
Scheme 2: Synthesis of fragment 9. Reagents and conditions: a) phthalimide, Pd2(allyl)2Cl2, ligand 15, Na2CO3...
Scheme 3: Synthesis of fragment 10. Reagents and conditions: a) TBSCl, NaH, THF, rt; b) phthalimide, PPh3, DE...
Scheme 4: Coupling of 9 and 10 and attempted ring-closing metathesis. Reagents and conditions: a) PPh3, DEAD,...
Scheme 5: Synthesis of alternative eastern fragment 23. Reagents and conditions: a) TBSCl, imidazole, CH2Cl2,...
Scheme 6: Synthesis of 4. Reagents and conditions: a) PPh3, DEAD, THF, 0 °C to rt; b) Grubbs–Hoveyda II (5 mo...
Scheme 7: Late stage functionalization of the pyrrolidine nitrogen. Reagents and conditions: A) (masked) alde...
Figure 2: Molecular X-ray structure of 3a, showing thermal displacement ellipsoids at the 50% probability lev...
Beilstein J. Org. Chem. 2018, 14, 2627–2645, doi:10.3762/bjoc.14.241
Graphical Abstract
Figure 1: The four quorum sensing systems in P. aeruginosa las, iqs, rhl, and pqs. Abbreviations: OdDHL, N-(3...
Figure 2: Schematic overview of the PQS biosynthesis and involvement of related metabolites and PqsE in virul...
Figure 3: Anthranilic acid (1) and derivatives thereof (2–4).
Figure 4: Crystal structure of 6-FABA-AMP in complex with PqsA.
Figure 5: Structures of substrate mimetic PqsA inhibitors.
Figure 6: Structures and characteristics of prominent classes of PqsD inhibitors.
Figure 7: Comparison of docking poses of three prototypic PqsD inhibitors: benzamidobenzoic acid derivative 12...
Figure 8: Structures and characteristics of hits against PqsD identified through different methods.
Figure 9: HHQ and PQS analogues as PqsD inhibitors and chemical probe used for screening.
Figure 10: Structure of PqsD-targeting biofilm inhibitor derived from linezolid.
Figure 11: Fragment-based PqsE-inhibitors 24–26.
Figure 12: PqsE co-crystal structures. (A) native product 2-ABA; (B–D) hit fragments 24–26.
Figure 13: Structurally diverse PqsBC-inhibitors 27–30.
Figure 14: Native PqsR ligand HHQ (31) which is converted into PQS (32) by PqsH and synthetic inhibitors 33 an...
Figure 15: Quinazolinone inhibitor 36 (QZN).
Figure 16: Crystal structure of QZN (36) in complex with PqsRCBD.
Figure 17: Structures of best fitting compounds 37–40 obtained from docking studies.
Figure 18: Initial hit 21 and optimized compound 42 (M64).
Figure 19: Co-crystal structure of M64 (42) with PqsRLBD.
Figure 20: M64 (42) as the starting point for further optimization leading to 43, which was further modified a...
Figure 21: Hit fragments from the benzamide (47–48) and oxadiazole class (49–51).
Figure 22: Structures of dual inhibitors 52–55.
Figure 23: Sulfonyl pyrimidines 56–58 acting as dual PqsD/PqsR inhibitors.
Beilstein J. Org. Chem. 2018, 14, 2468–2481, doi:10.3762/bjoc.14.223
Graphical Abstract
Figure 1: Various catalysts used for metathesis reactions.
Scheme 1: SM coupling and RCM protocol to substituted indene derivative 10.
Scheme 2: Synthesis of polycycles via SM and RCM approach.
Figure 2: Various angucyclines.
Scheme 3: SM coupling and RCM protocol to the benz[a]anthracene skeleton 26.
Scheme 4: Synthesis of substituted spirocycles via RCM and SM sequence.
Scheme 5: Synthesis of highly functionalized bis-spirocyclic derivative 37.
Scheme 6: Synthesis of spirofluorene derivatives via RCM and SM coupling sequence.
Scheme 7: Synthesis of truxene derivatives via RCM and SM coupling.
Scheme 8: Synthesis of substituted isoquinoline derivative via SM and RCM protocol.
Scheme 9: Synthesis to 8-aryl substituted coumarin 64 via RCM and SM sequence.
Scheme 10: Synthesis of cyclic sulfoximine 70 via SM and RCM as key steps.
Scheme 11: Synthesis of 1-benzazepine derivative 75 via SM and RCM as key steps.
Scheme 12: Synthesis of naphthoxepine derivative 79 via RCM followed by SM coupling.
Scheme 13: Sequential CM and SM coupling approach to Z-stilbene derivative 85.
Scheme 14: Synthesis of substituted trans-stilbene derivatives via SM coupling and RCM.
Scheme 15: Synthesis of biaryl derivatives via sequential EM, DA followed by SM coupling.
Scheme 16: Synthesis of the dibenzocyclooctadiene core of schisandrene.
Scheme 17: Synthesis of cyclophane 115 via SM coupling and RCM as key steps.
Scheme 18: Synthesis of cyclophane 120 and 122 via SM coupling and RCM as key steps.
Scheme 19: Synthesis of cyclophanes via SM and RCM.
Scheme 20: Synthesis of MK-6325 (141) via RCM and SM coupling.
Beilstein J. Org. Chem. 2018, 14, 2396–2403, doi:10.3762/bjoc.14.216
Graphical Abstract
Figure 1: a) Explosion was observed when an arylamine was mixed with aldehydes in the presence of IBX. b) Ben...
Figure 2: Comparison of the current work with the existing literature reports.
Figure 3: Synthesis of quinazolin-4(3H)-one derivatives from the reaction of 1 with liquid aldehydes. aYields...
Figure 4: Synthesis of quinazolin-4(3H)-one derivatives from reaction of 1 and solid aldehydes. aYields with ...
Figure 5: Crystal structure of 3a (CCDC No. 1823611).
Figure 6: Plausible mechanism for the quinazolin-4(3H)-ones synthesis using IBX.
Scheme 1: Large scale synthesis of 3a.
Beilstein J. Org. Chem. 2018, 14, 2366–2374, doi:10.3762/bjoc.14.212
Graphical Abstract
Scheme 1: (a) Our previously reported Cp*Co(III) redox-neutral coupling of 3-buten-2-one to benzamides, (b) p...
Scheme 2: Summary of reaction conditions optimisation.
Scheme 3: Substrate scope of Cp*Co(III)-catalysed coupling of 3-buten-2-one with functionalised acetanilides....
Figure 1: Mechanistic pathway for Cp*Co(III)-catalysed alkylation of acetanilide with 3-buten-2-one obtained ...
Figure 2: Comparison between energies during the Cp*Co(III)-catalysed coupling of 3-buten-2-one with acetanil...
Figure 3: Comparative visualisation of bcp for Int 2ketone with the acetanilide (left) and benzamide substrat...
Scheme 4: Competitive experiment between coupling to acetanilide (ring A) or benzamide (ring B). aMajor produ...
Beilstein J. Org. Chem. 2018, 14, 2035–2064, doi:10.3762/bjoc.14.179
Graphical Abstract
Figure 1: Depiction of the energy levels of a typical organic molecule and the photophysical processes it can...
Figure 2: General catalytic cycle of a photocatalyst in a photoredox organocatalysed reaction. [cat] – photoc...
Figure 3: Structures and names of the most common photocatalysts encountered in the reviewed literature.
Figure 4: General example of a reductive quenching catalytic cycle. [cat] – photocatalyst, [cat]* – photocata...
Figure 5: General example of an oxidative quenching catalytic cycle. [cat] – photocatalyst, [cat]* – photocat...
Scheme 1: Oxidative coupling of aldehydes and amines to amides using acridinium salt photocatalysis.
Figure 6: Biologically active molecules containing a benzamide linkage.
Scheme 2: The photocatalytic reduction of amino acids to produce the corresponding free or protected amines.
Scheme 3: The organocatalysed photoredox base-mediated oxidation of thiols to disulfides.
Scheme 4: C-Terminal modification of peptides and proteins using organophotoredox catalysis.
Scheme 5: The reduction and aryl coupling of aryl halides using a doubly excited photocatalyst (PDI).
Figure 7: Mechanism for the coupling of aryl halides using PDI, which is excited sequentially by two photons.
Scheme 6: The arylation of five-membered heteroarenes using arenediazonium salts under organophotoredox condi...
Scheme 7: The C–H (hetero)arylation of five-membered heterocycles under Eosin Y photocatalysis.
Scheme 8: The C–H sulfurisation of imidazoheterocycles using Eosin B-catalyzed photochemical methods.
Scheme 9: The introduction of the thiocyanate group using Eosin Y photocatalysis.
Scheme 10: Sulfonamidation of pyrroles using oxygen as the terminal oxidant.
Scheme 11: DDQ-catalysed C–H amination of arenes and heteroarenes.
Scheme 12: Photoredox-promoted radical Michael addition reactions of allylic or benzylic carbons.
Figure 8: Proposed mechanistic rationale for the observed chemoselectivities.
Scheme 13: The photocatalytic manipulation of C–H bonds adjacent to amine groups.
Scheme 14: The perylene-catalysed organophotoredox tandem difluoromethylation–acetamidation of styrene-type al...
Figure 9: Examples of biologically active molecules containing highly functionalised five membered heterocycl...
Scheme 15: The [3 + 2]-cycloaddition leading to the formation of pyrroles, through the reaction of 2H-azirines...
Figure 10: Proposed intermediate that determines the regioselectivity of the reaction.
Figure 11: Comparison of possible pathways of reaction and various intermediates involved.
Scheme 16: The acridinium salt-catalysed formation of oxazoles from aldehydes and 2H-azirines.
Scheme 17: The synthesis of oxazolines and thiazolines from amides and thioamides using organocatalysed photor...
Figure 12: Biologically active molecules on the market containing 1,3,4-oxadiazole moieties.
Scheme 18: The synthesis of 1,3,4-oxadiazoles from aldehyde semicarbazones using Eosin Y organophotocatalysis.
Scheme 19: The dimerization of primary thioamides to 1,2,4-thiadiazoles catalysed by the presence of Eosin Y a...
Scheme 20: The radical cycloaddition of o-methylthioarenediazonium salts and substituted alkynes towards the f...
Scheme 21: The dehydrogenative cascade reaction for the synthesis of 5,6-benzofused heterocyclic systems.
Figure 13: Trifluoromethylated version of compounds which have known biological activities.
Scheme 22: Eosin Y-catalysed photoredox formation of 3-substituted benzimidazoles.
Scheme 23: Oxidation of dihydropyrimidines by atmospheric oxygen using photoredox catalysis.
Scheme 24: Photoredox-organocatalysed transformation of 2-substituted phenolic imines to benzoxazoles.
Scheme 25: Visible light-driven oxidative annulation of arylamidines.
Scheme 26: Methylene blue-photocatalysed direct C–H trifluoromethylation of heterocycles.
Scheme 27: Photoredox hydrotrifluoromethylation of terminal alkenes and alkynes.
Scheme 28: Trifluoromethylation and perfluoroalkylation of aromatics and heteroaromatics.
Scheme 29: The cooperative asymmetric and photoredox catalysis towards the functionalisation of α-amino sp3 C–...
Scheme 30: Organophotoredox-catalysed direct C–H amidation of aromatics.
Scheme 31: Direct C–H alkylation of heterocycles using BF3K salts. CFL – compact fluorescent lamp.
Figure 14: The modification of camptothecin, demonstrating the use of the Molander protocol in LSF.
Scheme 32: Direct C–H amination of aromatics using acridinium salts.
Scheme 33: Photoredox-catalysed nucleophilic aromatic substitution of nucleophiles onto methoxybenzene derivat...
Scheme 34: The direct C–H cyanation of aromatics with a focus on its use for LSF.
Beilstein J. Org. Chem. 2018, 14, 1890–1900, doi:10.3762/bjoc.14.163
Graphical Abstract
Figure 1: Principle of photoaffinity labeling of proteins with diazirine derivatives. Photolabile ligands are...
Figure 2: FimH crystal structure (pdb code 1KLF) with docked p-nitrophenyl α-D-mannopyranoside (1, pNPMan). F...
Figure 3: Based on the structure of the known FimH ligands 1 and 2, three photolabile α-D-mannosides, 3–5, we...
Figure 4: Connolly representation of photolabile α-D-mannoside 3 in the closed gate (A, PDB code 1UWF) and op...
Scheme 1: Synthesis of photolabile α-D-mannosides 3 and 4. a) H2, Pd-C, methanol, rt, 6 h, 94%; b) HATU, DIPE...
Figure 5: ESIMS spectra of peptide M2 before (A) and after photoreaction (B) with mannoside 3.
Figure 6: Intact protein ESIMS spectra of FimHtr labeling with diazirine derivative 3 with (A) 50% acetonitri...
Beilstein J. Org. Chem. 2018, 14, 1051–1086, doi:10.3762/bjoc.14.93
Graphical Abstract
Figure 1: A figure showing the hydrogen bonding patterns observed in (a) duplex (b) triplex and (c) quadruple...
Figure 2: (a) Portions of MATα1–MATα2 are shown contacting the minor groove of the DNA substrate. Key arginin...
Figure 3: Chemical structures of naturally occurring and synthetic hybrid minor groove binders.
Figure 4: Synthetic structural analogs of distamycin A by replacing one or more pyrrole rings with other hete...
Figure 5: Pictorial representation of the binding model of pyrrole–imidazole (Py/Im) polyamides based on the ...
Figure 6: Chemical structures of synthetic “hairpin” pyrrole–imidazole (Py/Im) conjugates.
Figure 7: (a) Minor groove complex formation between DNA duplex and 8-ring cyclic Py/Im polyamide (conjugate ...
Figure 8: Telomere-targeting tandem hairpin Py/Im polyamides 23 and 24 capable of recognizing >10 base pairs; ...
Figure 9: Representative examples of recently developed DNA minor groove binders.
Figure 10: Chemical structures of bisbenzamidazoles Hoechst 33258 and 33342 and their synthetic structural ana...
Figure 11: Chemical structures of bisamidines such as diminazene, DAPI, pentamidine and their synthetic struct...
Figure 12: Representative examples of recently developed bisamidine derivatives.
Figure 13: Chemical structures of chromomycin, mithramycin and their synthetic structural analogs 91 and 92.
Figure 14: Chemical structures of well-known naturally occurring DNA binding intercalators.
Figure 15: Naturally occurring indolocarbazole rebeccamycin and its synthetic analogs.
Figure 16: Representative examples of naturally occurring and synthetic derivatives of DNA intercalating agent...
Figure 17: Several recent synthetic varieties of DNA intercalators.
Figure 18: Aminoglycoside (neomycin)–Hoechst 33258/intercalator conjugates.
Figure 19: Chemical structures of triazole linked neomycin dimers and neomycin–bisbenzimidazole conjugates.
Figure 20: Representative examples of naturally occurring and synthetic analogs of DNA binding alkylating agen...
Figure 21: Chemical structures of naturally occurring and synthetic analogs of pyrrolobenzodiazepines.
Beilstein J. Org. Chem. 2018, 14, 1021–1027, doi:10.3762/bjoc.14.88
Graphical Abstract
Figure 1: Selected examples of bioactive compounds containing the 2-oxazoline motif.
Figure 2: The catalytic difluorination of alkenes (top) and the proposed fluorocyclisation via the same I(I)/...
Figure 3: Substrate scope. aReaction conducted on 1 mmol scale. bReaction time increased to 40 hours. cReacti...
Scheme 1: Exploring diastereocontrol and the synthesis of the fluorohydrin 3. Yields in parentheses were dete...
Figure 4: X-ray molecular structure of compound 2c. Thermal ellipsoids shown at the 50% propability level. To...
Beilstein J. Org. Chem. 2018, 14, 593–602, doi:10.3762/bjoc.14.46
Graphical Abstract
Figure 1: Examples of synthetic pharmacologically active chiral 3-substituted isoindolinones.
Scheme 1: Retrosynthetic analysis of NH free chiral 3-substituted isoindolinones (3S)-1 and (3S)-2.
Scheme 2: Synthesis of parent benzamides 6–8.
Figure 2: Esters 12a–e, 13 prepared, isolated yield.
Figure 3: Benzamides 6a–d, 7a–e, 8 prepared, isolated yield.
Figure 4: Phase transfer catalysts (PTC) used in this study.
Scheme 3: Synthesis of isoindolinones 3a–d, 4a–e, 5; isolated yield, de by HPLC and 1H NMR. aAfter flash chro...
Scheme 4: Removal of the chiral auxiliary. Synthesis of isoindolinones 1a–c, 1e, 2; isolated yield, ee by HPL...
Figure 5: ORTEP plot of isoindolinone (2R,3S)-3a (CCDC 1590565) [68].
Scheme 5: Synthesis of pazinaclone analogue (3S)-27.
Beilstein J. Org. Chem. 2018, 14, 523–530, doi:10.3762/bjoc.14.38
Graphical Abstract
Figure 1: Acid strength (pKa) of various organic acids in acetonitrile or water (nr = not reported) [12-14].
Figure 2: Examples of functional molecules containing an N-triflylbenzamide.
Scheme 1: Synthesis of the strongly acidic benzamide derivatives.
Scheme 2: SNAr reactions of fluoro-substituted benzamide derivatives.
Scheme 3: Cross-coupling reactions of N-triflylbenzoic acid derivatives.
Scheme 4: Hydrolysis rates of the 4-bromobenzoic acid derivatives.
Figure 3: Content (percent) of super acids (0.5 mg/mL) over time (hours) in H3PO4/H2O/MeOH 17:3:20 at 50 °C.
Beilstein J. Org. Chem. 2017, 13, 1828–1849, doi:10.3762/bjoc.13.178
Graphical Abstract
Scheme 1: a) Schematic representations of unsubstituted urea, thiourea and guanidine. b) Wöhler's synthesis o...
Figure 1: Antidiabetic (1–3) and antimalarial (4) drugs derived from ureas and guanidines currently available...
Scheme 2: The structures of some representative (thio)urea and guanidine organocatalysts 5–8 and anion sensor...
Scheme 3: Solid-state reactivity of isothiocyanates reported by Kaupp [30].
Scheme 4: a) Mechanochemical synthesis of aromatic and aliphatic di- and trisubstituted thioureas by click-co...
Figure 2: The supramolecular level of organization of thioureas in the solid-state.
Figure 3: The supramolecular level of organization of thioureas in the solid-state.
Scheme 5: Thiourea-based organocatalysts and anion sensors obtained by click-mechanochemical synthesis.
Scheme 6: Mechanochemical desymmetrization of ortho-phenylenediamine.
Scheme 7: Mechanochemical desymmetrization of para-phenylenediamine.
Scheme 8: a) Selected examples of a mechanochemical synthesis of aromatic isothiocyanates from anilines. b) O...
Scheme 9: In solution, aromatic N-thiocarbamoyl benzotriazoles 27 are unstable and decompose to isothiocyanat...
Scheme 10: Mechanosynthesis of a) bis-thiocarbamoyl benzotriazole 29 and b) benzimidazole thione 31. c) Synthe...
Figure 4: In situ Raman spectroscopy monitoring the synthesis of thiourea 28d in the solid-state. N-Thiocarba...
Scheme 11: a) The proposed synthesis of monosubstituted thioureas 32. b) Conversion of N-thiocarbamoyl benzotr...
Scheme 12: A few examples of mechanochemical amination of thiocarbamoyl benzotriazoles by in situ generated am...
Scheme 13: Mechanochemical synthesis of a) anion binding urea 33 by amine-isocyanate coupling and b) dialkylur...
Scheme 14: a) Solvent-free milling synthesis of the bis-urea anion sensor 35. b) Non-selective desymmetrizatio...
Scheme 15: a) HOMO−1 contours of mono-thiourea 19b and mono-urea 36. b) Mechanochemical synthesis of hybrid ur...
Scheme 16: Synthesis of ureido derivatives 38 and 39 from KOCN and hydrochloride salts of a) L-phenylalanine m...
Scheme 17: a) K2CO3-assisted synthesis of sulfonyl (thio)ureas. b) CuCl-catalyzed solid-state synthesis of sul...
Scheme 18: Two-step mechanochemical synthesis of the antidiabetic drug glibenclamide (2).
Scheme 19: Derivatization of saccharin by mechanochemical CuCl-catalyzed addition of isocyanates.
Scheme 20: a) Unsuccessful coupling of p-toluenesulfonamide and DCC in solution and by neat/LAG ball milling. ...
Scheme 21: a) Expansion of the saccharin ring by mechanochemical insertion of carbodiimides. b) Insertion of D...
Scheme 22: Synthesis of highly basic biguanides by ball milling.
Beilstein J. Org. Chem. 2017, 13, 1564–1571, doi:10.3762/bjoc.13.156
Graphical Abstract
Figure 1: Prominent oxoaporphine and oxoisoaporphine alkaloids: liriodenine (1), menisporphine (2), dauriporp...
Scheme 1: Previously reported [7,17] and new approach to oxoisoaporphine alkaloids.
Scheme 2: Synthesis of iodinated isoquinolines 8a–c from alkoxy-substituted isoquinolines 7a–c.
Scheme 3: Synthesis of methyl 2-(isoquinolin-1-yl)benzoates 10a–c from 1-iodoisoquinolines 8a–c.
Scheme 4: Synthesis of the alkaloids 6-O-demethylmenisporphine (4), dauriporphinoline (5), and bianfugecine (6...
Scheme 5: Attempted synthesis of bianfugecine (6) via directed remote metalation and subsequent trapping of t...
Scheme 6: Outcome of a D2O quenching experiment after metalation of amide 12.
Scheme 7: Synthesis of 1-arylnaphthalene analogues 15 and 16.
Scheme 8: Outcome of a D2O quenching experiment after metalation of amide 16 with LDA.
Scheme 9: Synthesis of the alkaloids menisporphine (2) and dauriporphine (3) by O-methylation of the alkaloid...
Beilstein J. Org. Chem. 2017, 13, 1518–1523, doi:10.3762/bjoc.13.151
Graphical Abstract
Figure 1: Brominating reagents.
Scheme 1: Optimization of the substituents of the amide group. Reactions were run using 1 (0.1 mmol), 3a (0.0...
Scheme 2: Substrate scope. Reactions were run using 1 (0.1 mmol), 3a (0.01 mmol), and 4a (0.3 mmol) in EtOAc ...
Scheme 3: Reactions of substrates with substituted phenols.
Scheme 4: Reactions of monobrominated substrates.
Scheme 5: Rotational barriers of substrates and intermediates calculated at the B3YLP/6-31G(d) level of theor...
Scheme 6: Reaction of substrate with protected phenol.
Beilstein J. Org. Chem. 2016, 12, 2478–2489, doi:10.3762/bjoc.12.242
Graphical Abstract
Scheme 1: Preparation of the nitro derivatives 4a and 5a and the fluorine-containing compounds 4b and 5b. Rea...
Figure 1: 1H NMR spectra of compound 3a measured in five different solvents: (A) CDCl3, (B) DMSO-d6, (C) acet...
Figure 2: HSQC and H,H-COSY (small spectrum) of compound 3a measured in CDCl3 at 25 °C. The independent coupl...
Figure 3: Illustration of the general partial double bond character of an amide bond and the limited isomeriz...
Figure 4: Temperature-dependent 1H NMR spectra of 3a measured in DMSO-d6 (aliphatic region of the piperazine ...
Figure 5: Molecular structure of compound 3a (ORTEP plot with 50% probability level).
Figure 6: Molecular structure of compound 4b (ORTEP plot with 50% probability level).
Figure 7: Superimposition fit of the two conformers, which exist in the ratio of 1:1 in the solid state struc...
Scheme 2: Peptide labeling using the Huisgen-click reaction and building block 4b. Reagents and conditions: a...
Scheme 3: The traceless Staudinger ligation to yield compound 9. Reagents and conditions: a) acetonitrile/wat...
Scheme 4: Preparation of the radiolabeling building blocks [18F]4b and [18F]5b. Reagents and conditions: a) K[...
Figure 8: Radio-TLC (eluent: ethanol) of [18F]5b (Rf = 0.50; reaction mixture).
Figure 9: (Radio)HPLC of 5a (tR = 7.7 min, UV trace, red), 5b (tR = 6.7 min, UV trace: blue) and [18F]5b (tR ...
Beilstein J. Org. Chem. 2016, 12, 1203–1228, doi:10.3762/bjoc.12.116
Graphical Abstract
Figure 1: Two general pathways for conjugate addition followed by enantioselective protonation.
Scheme 1: Tomioka’s enantioselective addition of arylthiols to α-substituted acrylates.
Scheme 2: Sibi’s enantioselective hydrogen atom transfer reactions.
Scheme 3: Mikami’s addition of perfluorobutyl radical to α-aminoacrylate 11.
Scheme 4: Reisman’s Friedel–Crafts conjugate addition–enantioselective protonation approach toward tryptophan...
Scheme 5: Pracejus’s enantioselective addition of benzylmercaptan to α-aminoacrylate 20.
Scheme 6: Kumar and Dike’s enantioselective addition of thiophenol to α-arylacrylates.
Scheme 7: Tan’s enantioselective addition of aromatic thiols to 2-phthalimidoacrylates.
Scheme 8: Glorius’ enantioselective Stetter reactions with α-substituted acrylates.
Scheme 9: Dixon’s enantioselective addition of thiols to α-substituted acrylates.
Figure 2: Chiral phosphorous ligands.
Scheme 10: Enantioselective addition of arylboronic acids to methyl α-acetamidoacrylate.
Scheme 11: Frost’s enantioselective additions to dimethyl itaconate.
Scheme 12: Darses and Genet’s addition of potassium organotrifluoroborates to α-aminoacrylates.
Scheme 13: Proposed mechanism for enantioselective additions to α-aminoacrylates.
Scheme 14: Sibi’s addition of arylboronic acids to α-methylaminoacrylates.
Scheme 15: Frost’s enantioselective synthesis of α,α-dibenzylacetates 64.
Scheme 16: Rovis’s hydroheteroarylation of α-substituted acrylates with benzoxazoles.
Scheme 17: Proposed mechanism for the hydroheteroarylation of α-substituted acrylates with benzoxazoles.
Scheme 18: Sodeoka’s enantioselective addition of amines to N-benzyloxycarbonyl acrylamides 75 and 77.
Scheme 19: Proposed catalytic cycle for Sodeoka’s enantioselective addition of amines.
Scheme 20: Sibi’s enantioselective Friedel–Crafts addition of pyrroles to imides 84.
Scheme 21: Kobayashi’s enantioselective addition of malonates to α-substituted N-acryloyloxazolidinones.
Scheme 22: Chen and Wu’s enantioselective addition of thiophenol to N-methacryloyl benzamide.
Scheme 23: Tan’s enantioselective addition of secondary phosphine oxides and thiols to N-arylitaconimides.
Scheme 24: Enantioselective addition of thiols to α-substituted N-acryloylamides.
Scheme 25: Kobayashi’s enantioselective addition of thiols to α,β-unsaturated ketones.
Scheme 26: Feng’s enantioselective addition of pyrazoles to α-substituted vinyl ketones.
Scheme 27: Luo and Cheng’s addition of indoles to vinyl ketones by enamine catalysis.
Scheme 28: Curtin–Hammett controlled enantioselective addition of indole.
Scheme 29: Luo and Cheng’s enantioselective additions to α-branched vinyl ketones.
Scheme 30: Lou’s reduction–conjugate addition–enantioselective protonation.
Scheme 31: Luo and Cheng’s primary amine-catalyzed addition of indoles to α-substituted acroleins.
Scheme 32: Luo and Cheng’s proposed mechanism and transition state.
Figure 3: Shibasaki’s chiral lanthanum and samarium tris(BINOL) catalysts.
Scheme 33: Shibasaki’s enantioselective addition of 4-tert-butyl(thiophenol) to α,β-unsaturated thioesters.
Scheme 34: Shibasaki’s application of chiral (S)-SmNa3tris(binaphthoxide) catalyst 144 to the total synthesis ...
Scheme 35: Shibasaki’s cyanation–enantioselective protonation of N-acylpyrroles.
Scheme 36: Tanaka’s hydroacylation of acrylamides with aliphatic aldehydes.
Scheme 37: Ellman’s enantioselective addition of α-substituted Meldrum’s acids to terminally unsubstituted nit...
Scheme 38: Ellman’s enantioselective addition of thioacids to α,β,β-trisubstituted nitroalkenes.
Scheme 39: Hayashi’s enantioselective hydroarylation of diphenylphosphinylallenes.
Scheme 40: Hayashi’s enantioselective hydroarylation of diphenylphosphinylallenes.
Figure 4: Togni’s chiral ferrocenyl tridentate nickel(II) and palladium(II) complexes.
Scheme 41: Togni’s enantioselective hydrophosphination of methacrylonitrile.
Scheme 42: Togni’s enantioselective hydroamination of methacrylonitrile.
Beilstein J. Org. Chem. 2016, 12, 301–308, doi:10.3762/bjoc.12.32
Graphical Abstract
Scheme 1: Cascade 1,2-difunctionalization and cyclization to construct heterocycles.
Scheme 2: Cyclization of cyclohexane (2a) with substituted N-(2-methylallyl)benzamide (reaction conditions: 4...
Scheme 3: Cyclization of cycloalkanes with N-methyl-N-(2-methylallyl)benzamide (reaction conditions: 4a (0.2 ...
Scheme 4: Cyclization reaction of 6 with cyclohexane 2a (reaction conditions: 6 (0.2 mmol), cyclohexane 2a (2...
Scheme 5: Control experiments for the mechanism studies. a) Reaction with N-unprotected substrate 8a; b) reac...
Scheme 6: Proposed mechanism.
Beilstein J. Org. Chem. 2015, 11, 2209–2222, doi:10.3762/bjoc.11.240
Graphical Abstract
Scheme 1: Copper-catalyzed C–H amidation of tertiary amines.
Scheme 2: Copper-catalyzed C–H amidation and sulfonamidation of tertiary amines.
Scheme 3: Copper-catalyzed sulfonamidation of allylic C–H bonds.
Scheme 4: Copper-catalyzed sulfonamidation of benzylic C–H bonds.
Scheme 5: Copper-catalyzed sulfonamidation of C–H bonds adjacent to oxygen.
Scheme 6: Copper-catalyzed amidation and sulfonamidation of inactivated alkyl C–H bonds.
Scheme 7: Copper-catalyzed amidation and sulfonamidation of inactivated alkanes.
Scheme 8: Copper-catalyzed intramolecular C–H amidation for lactam synthesis.
Scheme 9: Copper-catalyzed intramolecular C–H amidation for lactam synthesis.
Scheme 10: Copper-catalyzed amidation/sulfonamidation of aryl C–H bonds.
Scheme 11: C–H amidation of pyridinylbenzenes and indoles.
Scheme 12: Mechanism of the Cu-catalyzed C2-amidation of indoles.
Scheme 13: Copper-catalyzed, 2-phenyl oxazole-assisted C–H amidation of benzamides.
Scheme 14: DG-assisted amidation/imidation of indole and benzene C–H bonds.
Scheme 15: Copper-catalyzed C–H amination/amidation of quinoline N-oxides.
Scheme 16: Copper-catalyzed aldehyde formyl C–H amidation.
Scheme 17: Copper-catalyzed formamide C–H amidation.
Scheme 18: Copper-catalyzed sulfonamidation of vinyl C–H bonds.
Scheme 19: CuCl2-catalyzed amidation/sulfonamidation of alkynyl C–H bonds.
Scheme 20: Cu(OH)2-catalyzed amidation/sulfonamidation of alkynyl C–H bonds.
Scheme 21: Sulfonamidation-based cascade reaction for the synthesis of tetrahydrotriazines.
Scheme 22: Copper-catalyzed cascade reaction for the synthesis of quinazolinones.
Scheme 23: Copper-catalyzed cascade reactions for the synthesis of fused quinazolinones.
Scheme 24: Copper-catalyzed synthesis of quinazolinones via methyl C–H bond amidation.
Scheme 25: Dicumyl peroxide-based cascade synthesis of quinazolinones.
Scheme 26: Copper-catalyzed cascade reactions for the synthesis of indolinones.