Search for "thiols" in Full Text gives 182 result(s) in Beilstein Journal of Organic Chemistry.
Beilstein J. Org. Chem. 2024, 20, 346–378, doi:10.3762/bjoc.20.35
Graphical Abstract
Scheme 1: Comparison between Barton and NHPI ester radical precursors.
Scheme 2: Overview of the mechanisms and activation modes involved in radical generation from RAEs.
Scheme 3: Common mechanisms in photocatalysis.
Scheme 4: A) Giese-type radical addition of NHPI esters mediated by a reductive quenching photocatalytic cycl...
Scheme 5: A) Minisci-type radical addition of NHPI esters. B) Reaction mechanism involving an “off-cycle” red...
Scheme 6: Activation of NHPI esters through hydrogen-bonding in an oxidative quenching photocatalytic cycle.
Scheme 7: SET activation of RAE facilitated by a Lewis acid catalyst.
Scheme 8: PCET activation of NHPI esters in the context of a radical-redox annulation.
Scheme 9: Activation enabled by a strong excited-state reductant catalyst and its application in the dearomat...
Scheme 10: Proposed formation of an intramolecular charge-transfer complex in the synthesis of (spiro)anellate...
Scheme 11: Formation of a charge-transfer complex between enamides and NHPI esters enabled by a chiral phospha...
Scheme 12: Activation of NHPI ester through the formation of photoactive EDA-complexes.
Scheme 13: A) EDA complex-mediated radical hydroalkylation reactions of NHPI esters. B) Proposed mechanism for...
Scheme 14: Proposed radical chain mechanism initiated by EDA-complex formation.
Scheme 15: A) Photoinduced decarboxylative borylation. B) Proposed radical chain mechanism.
Scheme 16: A) Activation of NHPI esters mediated by PPh3/NaI. B) Proposed catalytic cycle involving EDA-comple...
Scheme 17: A) Radical generation facilitated by EDA complex formation between PTH1 catalyst and NHPI esters. B...
Scheme 18: Proposed catalytic cycle for the difunctionalization of styrenes.
Scheme 19: Formation of a charge-transfer complex between NHPI esters and Cs2CO3 enables decarboxylative amina...
Scheme 20: 3-Acetoxyquinuclidine as catalytic donor in the activation of TCNHPI esters.
Scheme 21: A) Photoinduced Cu-catalyzed decarboxylative amination. B) Proposed catalytic cycle. C) Radical clo...
Scheme 22: A) Photoinduced Pd-catalyzed aminoalkylation of 1,4-dienes. B) Proposed catalytic cycle.
Scheme 23: A) TM-catalyzed decarboxylative coupling of NHPI esters and organometallic reagents. B) Representat...
Scheme 24: Synthetic applications of the TM-catalyzed decarboxylative coupling of NHPI esters and organometall...
Scheme 25: A) Ni-catalyzed cross-electrophile coupling of NHPI esters. B) Representative catalytic cycle.
Scheme 26: A) Synthetic applications of decarboxylative cross-electrophile couplings. B) Decarboxylative aryla...
Scheme 27: A) Activation of tetrachlorophthalimide redox-active esters enabled by a low-valency Bi complex. B)...
Scheme 28: Activation of NHPI esters mediated by Zn0 applied in a Z-selective alkenylation reaction.
Scheme 29: A) Activation of NHPI esters enabled by a pyridine-boryl radical species applied to the decarboxyla...
Scheme 30: A) Decarboxylative coupling of RAE and aldehydes enabled by NHC-catalyzed radical relay. B) Propose...
Scheme 31: A) Decarboxylative C(sp3)–heteroatom coupling reaction of NHPI esters under NHC catalysis B) The NH...
Scheme 32: A) Electrochemical Giese-type radical addition of NHPI esters. B) Reaction mechanism.
Scheme 33: Electrochemical Minisci-type radical addition of NHPI-esters.
Scheme 34: Ni-electrocatalytic cross-electrophile coupling of NHPI esters with aryl iodides.
Scheme 35: A) Decarboxylative arylation of NHPI esters under Ag-Ni electrocatalysis B) Formation of AgNP on th...
Scheme 36: Synthetic applications of decarboxylative couplings of NHPI esters under Ni-electrocatalysis.
Scheme 37: Examples of natural product syntheses in which RAEs were used in key C–C bond forming reactions.
Beilstein J. Org. Chem. 2023, 19, 1741–1754, doi:10.3762/bjoc.19.127
Graphical Abstract
Scheme 1: Synthesis of trifluoromethylpyrazoles from trifluoroacetaldehyde hydrazones.
Scheme 2: Synthesis of polysubstituted pyrazolidines and pyrazolines.
Scheme 3: Asymmetric synthesis of 3-trifluoromethyl-1,4-dihydropyridazines reported by Rueping et al. [39].
Scheme 4: Synthesis of 3-trifluoromethyl-1,4-dihydropyridazine with Brønsted acid-assisted Lewis base catalys...
Scheme 5: Synthesis of CF3-pyrazoles and CF3-1,6-dihydropyridazines.
Scheme 6: Asymmetric reactions of trifluoromethylimines with organometallic reagents.
Scheme 7: Mannich-type reaction of trifluoroacetaldehyde hydrazones.
Scheme 8: Synthesis of trifluoromethylated hydrazonoyl halides.
Scheme 9: Early work of trifluoromethylated hydrazonoyl halides.
Scheme 10: [3 + 2]/[3 + 3] Cycloadditions of trifluoromethylated hydrazonoyl halides.
Scheme 11: Substrate scope for [3 + 2] cycloadditions with trifluoroacetonitrile imines reported by Jasiński’s...
Scheme 12: Synthesis of trifluoromethylated 1,2,4-triazole and 1,2,4-triazine derivatives.
Scheme 13: [3 + 2] Cycloadditions of difluoromethylated hydrazonoyl halides.
Scheme 14: Preparation and early applications of trifluoromethylated acylhydrazones.
Scheme 15: 1,2-Nucleophilic addition reactions of trifluoromethylated acylhydrazones.
Scheme 16: Cascade oxidation/cyclization reactions of trifluoromethylated homoallylic acylhydrazines.
Scheme 17: Synthesis of trifluoromethylated cyanohydrazines and 3-trifluoromethyl-1,2,4-triazolines.
Scheme 18: N-Arylation and N-alkylation of trifluoromethyl acylhydrazones.
Scheme 19: [3 + 2]-Cycladditions of trifluoromethyl acylhydrazones.
Beilstein J. Org. Chem. 2023, 19, 1471–1502, doi:10.3762/bjoc.19.106
Graphical Abstract
Scheme 1: Sulfur-containing bioactive molecules.
Scheme 2: Scandium-catalyzed synthesis of thiosulfonates.
Scheme 3: Palladium-catalyzed aryl(alkyl)thiolation of unactivated arenes.
Scheme 4: Catalytic cycle for Pd-catalyzed aryl(alkyl)thiolation of unactivated arenes.
Scheme 5: Iron- or boron-catalyzed C–H arylthiation of substituted phenols.
Scheme 6: Iron-catalyzed azidoalkylthiation of alkenes.
Scheme 7: Plausible mechanism for iron-catalyzed azidoalkylthiation of alkenes.
Scheme 8: BF3·Et2O‑mediated electrophilic cyclization of aryl alkynoates.
Scheme 9: Tentative mechanism for BF3·Et2O‑mediated electrophilic cyclization of aryl alkynoates.
Scheme 10: Construction of 6-substituted benzo[b]thiophenes.
Scheme 11: Plausible mechanism for construction of 6-substituted benzo[b]thiophenes.
Scheme 12: AlCl3‑catalyzed cyclization of N‑arylpropynamides with N‑sulfanylsuccinimides.
Scheme 13: Synthetic utility of AlCl3‑catalyzed cyclization of N‑arylpropynamides with N‑sulfanylsuccinimides.
Scheme 14: Sulfenoamination of alkenes with sulfonamides and N-sulfanylsuccinimides.
Scheme 15: Lewis acid/Brønsted acid controlled Pd-catalyzed functionalization of aryl C(sp2)–H bonds.
Scheme 16: Possible mechanism for Lewis acid/Brønsted acid controlled Pd-catalyzed functionalization of aryl C...
Scheme 17: FeCl3-catalyzed carbosulfenylation of unactivated alkenes.
Scheme 18: Copper-catalyzed electrophilic thiolation of organozinc halides.
Scheme 19: h-BN@Copper(II) nanomaterial catalyzed cross-coupling reaction of sulfoximines and N‑(arylthio)succ...
Scheme 20: AlCl3‑mediated cyclization and sulfenylation of 2‑alkyn-1-one O‑methyloximes.
Scheme 21: Lewis acid-promoted 2-substituted cyclopropane 1,1-dicarboxylates with sulfonamides and N-(arylthio...
Scheme 22: Lewis acid-mediated cyclization of β,γ-unsaturated oximes and hydrazones with N-(arylthio/seleno)su...
Scheme 23: Credible pathway for Lewis acid-mediated cyclization of β,γ-unsaturated oximes with N-(arylthio)suc...
Scheme 24: Synthesis of 4-chalcogenyl pyrazoles via chalcogenation/cyclization of α,β-alkynic hydrazones.
Scheme 25: Controllable synthesis of 3-thiolated pyrroles and pyrrolines.
Scheme 26: Possible mechanism for controllable synthesis of 3-thiolated pyrroles and pyrrolines.
Scheme 27: Co-catalyzed C2-sulfenylation and C2,C3-disulfenylation of indole derivatives.
Scheme 28: Plausible catalytic cycle for Co-catalyzed C2-sulfenylation and C2,C3-disulfenylation of indoles.
Scheme 29: C–H thioarylation of electron-rich arenes by iron(III) triflimide catalysis.
Scheme 30: Difunctionalization of alkynyl bromides with thiosulfonates and N-arylthio succinimides.·
Scheme 31: Suggested mechanism for difunctionalization of alkynyl bromides with thiosulfonates and N-arylthio ...
Scheme 32: Synthesis of thioesters, acyl disulfides, ketones, and amides by N-thiohydroxy succinimide esters.
Scheme 33: Proposed mechanism for metal-catalyzed selective acylation and acylthiolation.
Scheme 34: AlCl3-catalyzed synthesis of 3,4-bisthiolated pyrroles.
Scheme 35: α-Sulfenylation of aldehydes and ketones.
Scheme 36: Acid-catalyzed sulfetherification of unsaturated alcohols.
Scheme 37: Enantioselective sulfenylation of β-keto phosphonates.
Scheme 38: Organocatalyzed sulfenylation of 3‑substituted oxindoles.
Scheme 39: Sulfenylation and chlorination of β-ketoesters.
Scheme 40: Intramolecular sulfenoamination of olefins.
Scheme 41: Plausible mechanism for intramolecular sulfenoamination of olefins.
Scheme 42: α-Sulfenylation of 5H-oxazol-4-ones.
Scheme 43: Metal-free C–H sulfenylation of electron-rich arenes.
Scheme 44: TFA-promoted C–H sulfenylation indoles.
Scheme 45: Proposed mechanism for TFA-promoted C–H sulfenylation indoles.
Scheme 46: Organocatalyzed sulfenylation and selenenylation of 3-pyrrolyloxindoles.
Scheme 47: Organocatalyzed sulfenylation of S-based nucleophiles.
Scheme 48: Conjugate Lewis base Brønsted acid-catalyzed sulfenylation of N-heterocycles.
Scheme 49: Mechanism for activation of N-sulfanylsuccinimide by conjugate Lewis base Brønsted acid catalyst.
Scheme 50: Sulfenylation of deconjugated butyrolactams.
Scheme 51: Intramolecular sulfenofunctionalization of alkenes with phenols.
Scheme 52: Organocatalytic 1,3-difunctionalizations of Morita–Baylis–Hillman carbonates.
Scheme 53: Organocatalytic sulfenylation of β‑naphthols.
Scheme 54: Acid-promoted oxychalcogenation of o‑vinylanilides with N‑(arylthio/arylseleno)succinimides.
Scheme 55: Lewis base/Brønsted acid dual-catalytic C–H sulfenylation of aryls.
Scheme 56: Lewis base-catalyzed sulfenoamidation of alkenes.
Scheme 57: Cyclization of allylic amide using a Brønsted acid and tetrabutylammonium chloride.
Scheme 58: Catalytic electrophilic thiocarbocyclization of allenes with N-thiosuccinimides.
Scheme 59: Suggested mechanism for electrophilic thiocarbocyclization of allenes with N-thiosuccinimides.
Scheme 60: Chiral chalcogenide-catalyzed enantioselective hydrothiolation of alkenes.
Scheme 61: Proposed mechanism for chalcogenide-catalyzed enantioselective hydrothiolation of alkenes.
Scheme 62: Organocatalytic sulfenylation for synthesis a diheteroatom-bearing tetrasubstituted carbon centre.
Scheme 63: Thiolative cyclization of yne-ynamides.
Scheme 64: Synthesis of alkynyl and acyl disulfides from reaction of thiols with N-alkynylthio phthalimides.
Scheme 65: Oxysulfenylation of alkenes with 1-(arylthio)pyrrolidine-2,5-diones and alcohols.
Scheme 66: Arylthiolation of arylamines with (arylthio)-pyrrolidine-2,5-diones.
Scheme 67: Catalyst-free isothiocyanatoalkylthiation of styrenes.
Scheme 68: Sulfenylation of (E)-β-chlorovinyl ketones toward 3,4-dimercaptofurans.
Scheme 69: HCl-promoted intermolecular 1, 2-thiofunctionalization of aromatic alkenes.
Scheme 70: Possible mechanism for HCl-promoted 1,2-thiofunctionalization of aromatic alkenes.
Scheme 71: Coupling reaction of diazo compounds with N-sulfenylsuccinimides.
Scheme 72: Multicomponent reactions of disulfides with isocyanides and other nucleophiles.
Scheme 73: α-Sulfenylation and β-sulfenylation of α,β-unsaturated carbonyl compounds.
Beilstein J. Org. Chem. 2023, 19, 1408–1442, doi:10.3762/bjoc.19.102
Graphical Abstract
Scheme 1: In situ generation of imidazolylidene carbene.
Scheme 2: Hg(II) complex of NHC.
Scheme 3: Isolable and bottlable carbene reported by Arduengo [3].
Scheme 4: First air-stable carbene synthesized by Arduengo in 1992 [5].
Figure 1: General structure of an NHC.
Figure 2: Stabilization of an NHC by donation of the lone pair electrons into the vacant p-orbital (LUMO) at ...
Figure 3: Abnormal NHC reported by Bertrand [8,9].
Figure 4: Cu(d) orbital to σ*C-N(NHC) interactions in NHC–CuX complexes computed at the B3LYP/def2-SVP level ...
Figure 5: Molecular orbital contributions to the NHC–metal bond.
Scheme 5: Synthesis of NHC–Cu(I) complexes by deprotonation of NHC precursors with a base.
Scheme 6: Synthesis of [NHC–CuX] complexes.
Scheme 7: Synthesis of [(ICy)CuX] and [(It-Bu)CuX] complexes.
Scheme 8: Synthesis of iodido-bridged copper–NHC complexes by deprotonation of benzimidazolium salts reported...
Scheme 9: Synthesis of copper complexes by deprotonation of triazolium salts.
Scheme 10: Synthesis of thiazolylidene–Cu(I) complex by deprotonation with KOt-Bu.
Scheme 11: Preparation of NHC–Cu(I) complexes.
Scheme 12: Synthesis of methylmalonic acid-derived anionic [(26a,b)CuCl]Li(THF)2 and zwitterionic (28) heterol...
Scheme 13: Synthesis of diaminocarbene and diamidocarbene (DAC)–Cu(I) complexes.
Scheme 14: Synthesis of the cationic (NHC)2Cu(I) complex 39 from benzimidazolium salts 38 with tetrakis(aceton...
Scheme 15: Synthesis of NHC and ADC (acyclic diamino carbenes) Cu(I) hexamethyldisilazide complexes reported b...
Scheme 16: Synthesis of NHC–copper(I) complexes using an acetylacetonate-functionalized imidazolium zwitterion...
Scheme 17: Synthesis of NHC–Cu(I) complexes through deprotonation of azolium salts with Cu2O.
Scheme 18: Synthesis of NHC–CuBr complex through deprotonation with Cu2O reported by Kolychev [31].
Scheme 19: Synthesis of chiral NHC–CuBr complexes from phenoxyimine-imidazolium salts reported by Douthwaite a...
Scheme 20: Preparation of linear neutral NHC–CuCl complexes through the use of Cu2O. For abbreviations, please...
Scheme 21: Synthesis of abnormal-NHC–copper(I) complexes by Bertrand, Cazin and co-workers [35].
Scheme 22: Microwave-assisted synthesis of thiazolylidene/benzothiazolylidene–CuBr complexes by Bansal and co-...
Scheme 23: Synthesis of NHC–CuX complexes through transmetallation.
Scheme 24: Preparation of six- or seven-membered NHC–Cu(I) complexes through transmetalation from Ag(I) comple...
Scheme 25: Synthesis of 1,2,3-triazolylidene–CuCl complexes through transmetallation of Ag(I) complexes genera...
Scheme 26: Synthesis of NHC–copper complexes having both Cu(I) and Cu(II) units through transmetalation report...
Scheme 27: Synthesis of new [(IPr(CH2)3Si(OiPr)3)CuX] complexes and anchoring on MCM-41.
Scheme 28: Synthesis of bis(trimethylsilyl)phosphide–Cu(I)–NHC complexes through ligand displacement.
Scheme 29: Synthesis of silyl- and stannyl [(NHC)Cu−ER3] complexes.
Scheme 30: Synthesis of amido-, phenolato-, thiophenolato–Cu(NHC) complexes.
Scheme 31: Synthesis of first isolable NHC–Cu–difluoromethyl complexes reported by Sanford et al. [44].
Scheme 32: Synthesis of NHC–Cu(I)–bifluoride complexes reported by Riant, Leyssens and co-workers [45].
Scheme 33: Conjugate addition of Et2Zn to enones catalyzed by an NHC–Cu(I) complex reported by Woodward in 200...
Scheme 34: Hydrosilylation of a carbonyl group.
Scheme 35: NHC–Cu(I)-catalyzed hydrosilylation of ketones reported by Nolan et al. [48,49].
Scheme 36: Application of chiral NHC–CuCl complex 104 for the enantioselective hydrosilylation of ketones.
Scheme 37: Hydrosilylation reactions catalyzed by NHC–Cu(Ot-Bu) complexes.
Scheme 38: NHC–CuCl catalyzed carbonylative silylation of alkyl halides.
Scheme 39: Nucleophilic conjugate addition to an activated C=C bond.
Figure 6: Molecular electrostatic potential maps (MESP) of two NHC–CuX complexes computed at the B3LYP/def2-S...
Scheme 40: Conjugate addition of Grignard reagents to 3-alkyl-substituted cyclohexenones catalyzed by a chiral...
Scheme 41: NHC–copper complex-catalyzed conjugate addition of Grignard reagent to 3-substituted hexenone repor...
Scheme 42: Conjugate addition or organoaluminum reagents to β-substituted cyclic enones.
Scheme 43: Conjugate addition of boronates to acyclic α,β-unsaturated carboxylic esters, ketones, and thioeste...
Scheme 44: NHC–Cu(I)-catalyzed hydroboration of an allene reported by Hoveyda [63].
Scheme 45: Conjugate addition of Et2Zn to cyclohexenone catalyzed by NHC–Cu(I) complex derived from benzimidaz...
Scheme 46: Asymmetric conjugate addition of diethylzinc to 3-nonen-2-one catalyzed by NHC–Cu complexes derived...
Scheme 47: General scheme of a [3 + 2] cycloaddition reaction.
Scheme 48: [3 + 2] Cycloaddition of azides with alkynes catalyzed by NHC–Cu(I) complexes reported by Diez-Gonz...
Scheme 49: Application of NHC–CuCl/N-donor combination to catalyze the [3 + 2] cycloaddition of benzyl azide w...
Scheme 50: [3 + 2] Cycloaddition of azides with acetylenes catalyzed by bis(NHC)–Cu complex 131 and mixed NHC–...
Figure 7: NHC–CuCl complex 133 as catalyst for the [3 + 2] cycloaddition of alkynes with azides at room tempe...
Scheme 51: [3 + 2] Cycloaddition of a bulky azide with an alkynylpyridine using [(NHC)Cu(μ-I)2Cu(NHC)] copper ...
Scheme 52: [3 + 2] Cycloaddition of benzyl azide with phenylacetylene under homogeneous and heterogeneous cata...
Scheme 53: [3 + 2] Cycloaddition of benzyl azide with acetylenes catalyzed by bisthiazolylidene dicopper(I) co...
Figure 8: Copper (I)–NHC linear coordination polymer 137 and its conversion into tetranuclear (138) and dinuc...
Scheme 54: An A3 reaction.
Scheme 55: Synthesis of SiO2-immobilized NHC–Cu(I) catalyst 141 and its application in the A3-coupling reactio...
Scheme 56: Preparation of dual-purpose Ru@SiO2–[(NHC)CuCl] catalyst system 142 developed by Bordet, Leitner an...
Scheme 57: Application of the catalyst system Ru@SiO2–[Cu(NHC)] 142 to the one-pot tandem A3 reaction and hydr...
Scheme 58: A3 reaction of phenylacetylene with secondary amines and aldehydes catalyzed by benzothiazolylidene...
Figure 9: Kohn–Sham HOMOs of phenylacetylene and NHC–Cu(I)–phenylacetylene complex computed at the B3LYP/def2...
Figure 10: Energies of the FMOs of phenylacetylene, iminium ion, and NHC–Cu(I)–phenylacetylene complex compute...
Scheme 59: NHC–Cu(I) catalyzed diboration of ketones 147 by reacting with bis(pinacolato)diboron (148) reporte...
Scheme 60: Protoboration of terminal allenes catalyzed by NHC–Cu(I) complexes reported by Hoveyda and co-worke...
Scheme 61: NHC–CuCl-catalyzed borylation of α-alkoxyallenes to give 2-boryl-1,3-butadienes.
Scheme 62: Regioselective hydroborylation of propargylic alcohols and ethers catalyzed by NHC–CuCl complexes 1...
Scheme 63: NHC–CuOt-Bu-catalyzed semihydrogenation and hydroborylation of alkynes.
Scheme 64: Enantioselective NHC–Cu(I)-catalyzed hydroborations of 1,1-disubstituted aryl olefins reported by H...
Scheme 65: Enantioselective NHC–Cu(I)-catalyzed hydroboration of exocyclic 1,1-disubstituted alkenes reported ...
Scheme 66: Markovnikov-selective NHC–CuOH-catalyzed hydroboration of alkenes and alkynes reported by Jones et ...
Scheme 67: Dehydrogenative borylation and silylation of styrenes catalyzed by NHC–CuOt-Bu complexes developed ...
Scheme 68: N–H/C(sp2)–H carboxylation catalyzed by NHC–CuOH complexes.
Scheme 69: C–H Carboxylation of benzoxazole and benzothiazole derivatives with CO2 using a 1,2,3-triazol-5-yli...
Scheme 70: Use of Cu(I) complex derived from diethylene glycol-functionalized imidazo[1,5,a] pyridin-3-ylidene...
Scheme 71: Allylation and alkenylation of polyfluoroarenes and heteroarenes catalyzed by NHC–Cu(I) complexes r...
Scheme 72: Enantioselective C(sp2)–H allylation of (benz)oxazoles and benzothiazoles with γ,γ-disubstituted pr...
Scheme 73: C(sp2)–H arylation of arenes catalyzed by dual NHC–Cu/NHC–Pd catalytic system.
Scheme 74: C(sp2)–H Amidation of (hetero)arenes with N-chlorocarbamates/N-chloro-N-sodiocarbamates catalyzed b...
Scheme 75: NHC–CuI catalyzed thiolation of benzothiazoles and benzoxazoles.
Beilstein J. Org. Chem. 2023, 19, 1198–1215, doi:10.3762/bjoc.19.88
Graphical Abstract
Figure 1: Diagram comparing the two reaction pathways for sacrificial electron donors (SD) in photocatalyzed ...
Figure 2: Diagram showing water-splitting systems developed by Girault, Scanlon, and co-workers that employ i...
Figure 3: Diagram illustrating the transfer of electrons in a photocatalytic particulate suspensions Z-scheme...
Figure 4: A. Structures of the molecules represented in part B. The numbers in brackets correspond to the com...
Figure 5: A. Structures of the molecules represented in part B. The numbers in brackets correspond to the com...
Beilstein J. Org. Chem. 2023, 19, 566–574, doi:10.3762/bjoc.19.41
Graphical Abstract
Scheme 1: Selected examples of the chiral ligands used for synthesis of the Ni(II)–Schiff base complexes.
Scheme 2: Synthesis of the chiral ligand L7 and its Ni(II) complexes with glycine, serine, dehydroalanine, an...
Figure 1: Fragment of the NOESY spectrum of the ʟ-(oBrCysNi)L7 complex indicating the correlation between the...
Figure 2: Low-gradient isosurfaces with low densities (blue color of the isosurface corresponds to the hydrog...
Figure 3: Saturated solutions of (GlyNi)L1 (left) and (GlyNi)L7 (right) in diethyl ether.
Figure 4: The CV curves observed for (GlyNi)L7 and (ΔAlaNi)L7 in the anodic and cathodic regions (Pt, CH3CN, ...
Beilstein J. Org. Chem. 2023, 19, 325–348, doi:10.3762/bjoc.19.28
Graphical Abstract
Scheme 1: Group 13 exchange.
Scheme 2: Borane-catalysed hydroboration of alkynes and the proposed mechanism.
Scheme 3: a) Borane-catalysed hydroboration of alkenes and the proposed mechanism. b) H-B-9-BBN-catalysed dou...
Scheme 4: a) Amine-borane-catalysed C‒H borylation of heterocycles and the proposed mechanism. b) Benzoic aci...
Scheme 5: Bis(pentafluorophenyl)borane-catalysed dimerisation of allenes and the proposed mechanism.
Scheme 6: Alkoxide-promoted hydroboration of heterocycles and the proposed mechanism.
Scheme 7: Borane-catalysed reduction of indoles and the proposed mechanism.
Scheme 8: H-B-9-BBN-catalysed hydrocyanation of enones and the proposed mechanism.
Scheme 9: Borane-catalysed hydroboration of nitriles and the proposed mechanism.
Scheme 10: Myrtanylborane-catalysed asymmetric reduction of propargylic ketones and the proposed mechanism.
Scheme 11: H-B-9-BBN-catalysed C–F esterification of alkyl fluorides and the proposed mechanism.
Scheme 12: H-B-9-BBN-catalysed 1,4-hydroboration of enones and the proposed mechanism.
Scheme 13: Boric acid-promoted reduction of esters, lactones, and carbonates and the proposed mechanism.
Scheme 14: H-B-9-BBN-catalysed reductive aldol-type reaction and the proposed mechanism.
Scheme 15: H-B-9-BBN-catalysed diastereoselective allylation of ketones and the Ph-BBD-catalysed enantioselect...
Scheme 16: H-B-9-BBN-catalysed C–F arylation of benzyl fluorides and the proposed mechanism.
Scheme 17: Borane-catalysed S‒H borylation of thiols and the proposed mechanism.
Scheme 18: Borane-catalysed hydroalumination of alkenes and allenes.
Scheme 19: a) Aluminium-catalysed hydroboration of alkynes and example catalysts. b) Deprotonation mechanistic...
Scheme 20: Aluminium-catalysed hydroboration of alkenes and the proposed mechanism.
Scheme 21: Aluminium-catalysed C–H borylation of terminal alkynes and the proposed mechanism.
Scheme 22: Aluminium-catalysed dehydrocoupling of amines, alcohols, and thiols with H-B-9-BBN or HBpin and the...
Scheme 23: Aluminium-catalysed hydroboration of unsaturated compounds and the general reaction mechanism.
Scheme 24: a) Gallium-catalysed asymmetric hydroboration of ketones and the proposed mechanism. b) Gallium-cat...
Scheme 25: Gallium(I)-catalysed allylation/propargylation of acetals and aminals and the proposed mechanism.
Scheme 26: Indium(I)-catalysed allylation/propargylation of acetals, aminals, and alkyl ethers.
Scheme 27: Iron–indium cocatalysed double hydroboration of nitriles and the proposed mechanism.
Figure 1: a) The number of reports for a given group 13 exchange in catalysis. b) Average free energy barrier...
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, 1225–1235, doi:10.3762/bjoc.18.128
Graphical Abstract
Figure 1: Representation of (a) cavitation and elongational flow caused by pulsed ultrasonication, (b) mixer ...
Scheme 1: (a) Mechanochemical activation of anthracene–endoperoxide mechanophore incorporated in the cross-li...
Scheme 2: Mechanochemical activation of dendronized polymer-based compound 4 by ultrasonication and ball mill...
Figure 2: Structure of cellulose and chitin and approximation to the structure of lignin.
Figure 3: Tensile forces by ball milling change the conformation of a chitin model compound. This deformation...
Figure 4: (a) Representation of a collision between the ball and a particle of a chitin sample and (b) mechan...
Figure 5: (a) Ultrasound-induced ATRP using piezoelectric BaTiO3 and (b) mechanochemical atom transfer radica...
Figure 6: Mechanochemical solid-state complexation of organic capsule 5 with fullerenes C70 in a planetary ba...
Scheme 3: Comparative mechanochemical dissociation of the central C–C bond in TASN derivatives 6 and 8.
Beilstein J. Org. Chem. 2022, 18, 1166–1176, doi:10.3762/bjoc.18.121
Graphical Abstract
Figure 1: Cyclic voltammograms obtained for complexes 1 (black), 2 (blue), 3 (green), 4 (red) (MeCN, 0.05 M Bu...
Scheme 1: Synthesis of complex 4.
Figure 2: Key correlations in the NOESY spectrum of complex (S)-4 and the corresponding characteristic fragme...
Scheme 2: Reductive three-membered ring-opening and follow-up chemical steps.
Figure 3: Correlations in the HMBC spectra of 6a and 6b and spin coupling constants in the 1H NMR spectrum of ...
Scheme 3: Electrochemically induced ring-opening followed by intramolecular cyclization.
Scheme 4: One-pot multistep approach to the cysteine derivatives.
Figure 4: Characteristic correlations in the NOESY spectra of diastereomeric complexes 10 and the correspondi...
Beilstein J. Org. Chem. 2022, 18, 524–532, doi:10.3762/bjoc.18.54
Graphical Abstract
Figure 1: The structures of chloroquine, hydroxychloroquine, and amodiaquine.
Scheme 1: Synthesis of 3-azolylpyrazoles 3a–c.
Scheme 2: Assumed mechanism for the formation of 1H-pyrazoles 3a–c.
Scheme 3: Synthesis of 3-aminopyrazoles 5b–k and 5-aminopyrazoles 5a and 5l–o.
Scheme 4: Orientation of nucleophilic attack of 7-chloro-4-hydrazinylquinoline on nitrobutadienes 4.
Scheme 5: Synthesis of oxazolidine 6 and pyrazole 7.
Scheme 6: A plausible mechanism for the formation of pyrazole 7.
Scheme 7: Synthesis of pyrazoles 9 and sulfoxide 10d.
Scheme 8: Synthesis of pyrazole 11.
Beilstein J. Org. Chem. 2022, 18, 381–419, doi:10.3762/bjoc.18.43
Graphical Abstract
Figure 1: Natural bioactive naphthoquinones.
Figure 2: Chemical structures of vitamins K.
Figure 3: Redox cycle of menadione.
Scheme 1: Selected approaches for menadione synthesis using silver(I) as a catalyst.
Scheme 2: Methylation approaches for the preparation of menadione from 1,4-naphthoquinone using tert-butyl hy...
Scheme 3: Methylation approach of 1,4-naphthoquinone using i) rhodium complexes/methylboronic acid and ii) bi...
Scheme 4: Synthesis of menadione (10) from itaconic acid.
Scheme 5: Menadione synthesis via Diels–Alder reaction.
Scheme 6: Synthesis of menadione (10) using p-cresol as a synthetic precursor.
Scheme 7: Synthesis of menadione (10) via demethoxycarbonylating annulation of methyl methacrylate.
Scheme 8: Furan 34 used as a diene in a Diels–Alder reaction for the synthesis of menadione (10).
Scheme 9: o-Toluidine as a dienophile in a Diels–Alder reaction for the synthesis of menadione (10).
Scheme 10: Representation of electrochemical synthesis of menadione.
Figure 4: Reaction sites and reaction types of menadione as substrate.
Scheme 11: DBU-catalyzed epoxidation of menadione (10).
Scheme 12: Phase-transfer catalysis for the epoxidation of menadione.
Scheme 13: Menadione epoxidation using a hydroperoxide derived from (+)-norcamphor.
Scheme 14: Enantioselective Diels–Alder reaction for the synthesis of asymmetric quinone 50 catalyzed by a chi...
Scheme 15: Optimized reaction conditions for the synthesis of anthra[9,1-bc]pyranone.
Scheme 16: Synthesis of anthra[9,1-bc]furanone, anthra[9,1-bc]pyridine, and anthra[9,1-bc]pyrrole derivatives.
Scheme 17: Synthesis of derivatives employing protected trienes.
Scheme 18: Synthesis of cyclobutene derivatives of menadione.
Scheme 19: Menadione reduction reactions using sodium hydrosulfite.
Scheme 20: Green methodology for menadiol synthesis and pegylation.
Scheme 21: Menadione reduction by 5,6-O-isopropylidene-ʟ-ascorbic acid under UV light irradiation.
Scheme 22: Selected approaches of menadione hydroacetylation to diacetylated menadiol.
Scheme 23: Thiele–Winter reaction catalyzed by Bi(OTf)3.
Scheme 24: Carbonyl condensation of menadione using resorcinol and a hydrazone derivative.
Scheme 25: Condensation reaction of menadione with thiosemicarbazide.
Scheme 26: Condensation reaction of menadione with acylhydrazides.
Scheme 27: Menadione derivatives functionalized with organochalcogens.
Scheme 28: Synthesis of selenium-menadione conjugates derived from chloromethylated menadione 84.
Scheme 29: Menadione alkylation by the Kochi–Anderson method.
Scheme 30: Menadione alkylation by diacids.
Scheme 31: Menadione alkylation by heterocycles-substituted carboxylic acids.
Scheme 32: Menadione alkylation by bromoalkyl-substituted carboxylic acids.
Scheme 33: Menadione alkylation by complex carboxylic acids.
Scheme 34: Kochi–Anderson method variations for the menadione alkylation via oxidative decarboxylation of carb...
Scheme 35: Copper-catalyzed menadione alkylation via free radicals.
Scheme 36: Nickel-catalyzed menadione cyanoalkylation.
Scheme 37: Iron-catalyzed alkylation of menadione.
Scheme 38: Selected approaches to menadione alkylation.
Scheme 39: Menadione acylation by photo-Friedel–Crafts acylation reported by Waske and co-workers.
Scheme 40: Menadione acylation by Westwood procedure.
Scheme 41: Synthesis of 3-benzoylmenadione via metal-free TBAI/TBHP system.
Scheme 42: Michael-type addition of amines to menadione reported by Kallmayer.
Scheme 43: Synthesis of amino-menadione derivatives using polyalkylamines.
Scheme 44: Selected examples for the synthesis of different amino-substituted menadione derivatives.
Scheme 45: Selected examples of Michael-type addition of complex amines to menadione (10).
Scheme 46: Addition of different natural α-amino acids to menadione.
Scheme 47: Michael-type addition of amines to menadione using silica-supported perchloric acid.
Scheme 48: Indolylnaphthoquinone or indolylnaphthalene-1,4-diol synthesis reported by Yadav et al.
Scheme 49: Indolylnaphthoquinone synthesis reported by Tanoue and co-workers.
Scheme 50: Indolylnaphthoquinone synthesis from menadione by Escobeto-González and co-workers.
Scheme 51: Synthesis of menadione analogues functionalized with thiols.
Scheme 52: Synthesis of menadione-derived symmetrical derivatives through reaction with dithiols.
Scheme 53: Mercaptoalkyl acids as nucleophiles in Michael-type addition reaction to menadione.
Scheme 54: Reactions of menadione (10) with cysteine derivatives for the synthesis of quinoproteins.
Scheme 55: Synthesis of menadione-glutathione conjugate 152 by Michael-type addition.
Beilstein J. Org. Chem. 2022, 18, 174–181, doi:10.3762/bjoc.18.19
Graphical Abstract
Figure 1: Naturally occurring HDAC inhibitors.
Figure 2: Naturally occurring HDAC inhibitors with different zinc-binding motifs.
Scheme 1: Planned syntheses of Cyl-1 derivatives.
Scheme 2: Cyl-1 derivatives via peptide Claisen rearrangement.
Scheme 3: Synthesis of tetrapeptide allyl esters 8.
Scheme 4: Synthesis and late stage modifications of Cyl derivatives.
Beilstein J. Org. Chem. 2021, 17, 2680–2715, doi:10.3762/bjoc.17.182
Graphical Abstract
Figure 1: Representative modified 1,3-oxathiolane nucleoside analogues.
Figure 2: Mechanism of antiviral action of 1,3-oxathiolane nucleosides, 3TC (1) and FTC (2), as chain termina...
Figure 3: Synthetic strategies for the construction of the 1,3-oxathiolane sugar ring.
Scheme 1: Synthesis of 4 from benzoyloxyacetaldehyde (3a) and 2-mercapto-substituted dimethyl acetal 3na.
Scheme 2: Synthesis of 8 from protected glycolic aldehyde 3b and 2-mercaptoacetic acid (3o).
Scheme 3: Synthesis of 20 from ᴅ-mannose (3c).
Scheme 4: Synthesis of 20 from 1,6-thioanhydro-ᴅ-galactose (3d).
Scheme 5: Synthesis of 8 from 2-(tert-butyldiphenylsilyloxy)methyl-5-oxo-1,2-oxathiolane (3m).
Scheme 6: Synthesis of 20a from ʟ-gulose derivative 3f.
Scheme 7: Synthesis of 31 from (+)-thiolactic acid 3p and 2-benzoyloxyacetaldehyde (3a).
Scheme 8: Synthesis of 35a from 1,4-dithiane-2,5-diol (3q) and glyoxylic acid (3g) hydrate.
Scheme 9: Synthetic routes toward 41 through Pummerer reaction from methyl 2-mercaptoacetate (3j) and bromoac...
Scheme 10: Strategy for the synthesis of 2,5-substituted 1,3-oxathiolane 41a using 4-nitrobenzyl glyoxylate an...
Scheme 11: Synthesis of 44 by a resolution method using Mucor miehei lipase.
Scheme 12: Synthesis of 45 from benzoyloxyacetaldehyde (3a) and 2-mercaptoacetaldehyde bis(2-methoxyethyl) ace...
Scheme 13: Synthesis of 46 from 2-mercaptoacetaldehyde bis(2-methoxyethyl) acetal (3nc) and diethyl 3-phosphon...
Scheme 14: Synthesis of 48 from 1,3-dihydroxyacetone dimer 3l.
Scheme 15: Approach toward 52 from protected alkene 3rb and lactic acid derivative 51 developed by Snead et al....
Scheme 16: Recent approach toward 56a developed by Kashinath et al.
Scheme 17: Synthesis of 56a from ʟ-menthyl glyoxylate (3h) hydrate by DKR.
Scheme 18: Possible mechanism with catalytic TEA for rapid interconversion of isomers.
Scheme 19: Synthesis of 35a by a classical resolution method through norephedrine salt 58 formation.
Scheme 20: Synthesis of 63 via [1,2]-Brook rearrangement from silyl glyoxylate 61 and thiol 3nb.
Scheme 21: Combined use of STS and CAL-B as catalysts to synthesize an enantiopure oxathiolane precursor 65.
Scheme 22: Synthesis of 1 and 1a from glycolaldehyde dimer 64 and 1,4-dithiane-2,5-diol (3q) using STS and CAL...
Scheme 23: Synthesis of 68 by using Klebsiella oxytoca.
Scheme 24: Synthesis of 71 and 72 using Trichosporon taibachii lipase and kinetic resolution.
Scheme 25: Synthesis of 1,3-oxathiolan-5-ones 77 and 78 via dynamic covalent kinetic resolution.
Figure 4: Pathway for glycosidic bond formation.
Scheme 26: First synthesis of (±)-BCH-189 (1c) by Belleau et al.
Scheme 27: Enantioselective synthesis of 3TC (1).
Scheme 28: Synthesis of cis-diastereomer 3TC (1) from oxathiolane propionate 44.
Scheme 29: Synthesis of (±)-BCH-189 (1c) via SnCl4-mediated N-glycosylation of 8.
Scheme 30: Synthesis of (+)-BCH-189 (1a) via TMSOTf-mediated N-glycosylation of 20.
Scheme 31: Synthesis of 3TC (1) from oxathiolane precursor 20a.
Scheme 32: Synthesis of 83 via N-glycosylation of 20 with pyrimidine bases.
Scheme 33: Synthesis of 85 via N-glycosylation of 20 with purine bases.
Scheme 34: Synthesis of 86 and 87 via N-glycosylation using TMSOTf and pyrimidines.
Scheme 35: Synthesis of 90 and 91 via N-glycosylation using TMSOTf and purines.
Scheme 36: Synthesis of 3TC (1) via TMSI-mediated N-glycosylation.
Scheme 37: Stereoselective N-glycosylation for the synthesis of 1 by anchimeric assistance of a chiral auxilia...
Scheme 38: Whitehead and co-workers’ approach for the synthesis of 1 via direct N-glycosylation without an act...
Scheme 39: ZrCl4-mediated stereoselective N-glycosylation.
Scheme 40: Plausible reaction mechanism for stereoselective N-glycosylation using ZrCl4.
Scheme 41: Synthesis of enantiomerically pure oxathiolane nucleosides 1 and 2.
Scheme 42: Synthesis of tetrazole analogues of 1,3-oxathiolane nucleosides 97.
Scheme 43: Synthetic approach toward 99 from 1,3-oxathiolane 45 by Camplo et al.
Scheme 44: Synthesis of 100 from oxathiolane phosphonate analogue 46.
Scheme 45: Synthetic approach toward 102 and the corresponding cyclic thianucleoside monophosphate 102a by Cha...
Scheme 46: Synthesis of emtricitabine (2) from 1,4-dithiane-2,5-diol (3q) and glyoxylic acid (3g).
Scheme 47: Synthesis of 1 and 2, respectively, from 56a–d using iodine-mediated N-glycosylation.
Scheme 48: Plausible mechanism for silane- and I2-mediated N-glycosylation.
Scheme 49: Pyridinium triflate-mediated N-glycosylation of 35a.
Scheme 50: Possible pathway for stereoselective N-glycosylation via in situ chelation with a metal ligand.
Scheme 51: Synthesis of novel 1,3-oxathiolane nucleoside 108 from oxathiolane precursor 8 and 3-benzyloxy-2-me...
Scheme 52: Synthesis of 110 using T-705 as a nucleobase and 1,3-oxathiolane derivative 8 via N-glycosylation.
Scheme 53: Synthesis of 1 using an asymmetric leaving group and N-glycosylation with bromine and mesitylene.
Scheme 54: Cytidine deaminase for enzymatic separation of 1c.
Scheme 55: Enzymatic resolution of the monophosphate derivative 116 for the synthesis of (−)-BCH-189 (1) and (...
Scheme 56: Enantioselective resolution by PLE-mediated hydrolysis to obtain FTC (2).
Scheme 57: (+)-Menthyl chloroformate as a resolving agent to separate a racemic mixture 120.
Scheme 58: Separation of racemic mixture 1c by cocrystal 123 formation with (S)-(−)-BINOL.
Beilstein J. Org. Chem. 2021, 17, 2642–2649, doi:10.3762/bjoc.17.177
Graphical Abstract
Scheme 1: Selected methods for the synthesis of enantioenriched β-silyl nitroalkanes, synthesis of chiral org...
Scheme 2: Scope of substrates. Reaction conditions: 1 (0.2 mmol), 2 (0.5 mmol), catalyst VII (0.01 mmol, 5 mo...
Scheme 3: Synthesis of ent-3. Reaction conditions: 1 (0.2 mmol), 2 (0.5 mmol), catalyst VIII (0.01 mmol, 5 mo...
Scheme 4: Organocatalytic 1,4-conjuagte addition of nitromethane (2) to enone 3o.
Figure 1: Single crystal X-ray structure of ent-3k (CCDC 2097263).
Scheme 5: Preparative scale synthesis of 3c and ent-3d.
Beilstein J. Org. Chem. 2021, 17, 2553–2569, doi:10.3762/bjoc.17.171
Graphical Abstract
Figure 1: Schematic representation of the process of aqueous cryogel formation, using (a) monomers/small mole...
Figure 2: Microarchitecture of gelatin cryogels. (A) Surface and cross-sectional SEM micrographs of highly po...
Figure 3: Principle of 3D-cryogel printing. A) Illustration of 3D-printing of cryogels. B) Illustration of th...
Figure 4: Illustration of the production of the injectable multifunctional composite, comprised of alginate c...
Figure 5: Digital and SEM photographs of PETEGA cryogel at 20 °C (top) and 50 °C (bottom), synthesised via UV...
Figure 6: Cell morphology of T47D breast cancer cells cultured in HA cryogels. (A) Schematic representation o...
Figure 7: Preparation of PDMA/β-CD cryogel via cryogenic treatment and photochemical crosslinking in frozen s...
Figure 8: (A) Healing rate of wounds treated with autoclaved CG11 cryogels and those treated with 70% ethanol...
Figure 9: In vivo haemostatic capacity evaluation of the cryogels. Blood loss (a) and haemostatic time (b) in...
Beilstein J. Org. Chem. 2021, 17, 2520–2542, doi:10.3762/bjoc.17.169
Graphical Abstract
Scheme 1: Photoredox catalysis mechanism of [Ru(bpy)3]2+.
Scheme 2: Photoredox catalysis mechanism of CuI.
Scheme 3: Ligands and CuI complexes.
Scheme 4: Mechanism of CuI-based photocatalysis.
Scheme 5: Mechanisms of CuI–substrate complexes.
Scheme 6: Mechanism of CuII-base photocatalysis.
Scheme 7: Olefinic C–H functionalization and allylic alkylation.
Scheme 8: Cross-coupling of unactivated alkenes and CF3SO2Cl.
Scheme 9: Chlorosulfonylation/cyanofluoroalkylation of alkenes.
Scheme 10: Hydroamination of alkenes.
Scheme 11: Cross-coupling reaction of alkenes, alkyl halides with nucleophiles.
Scheme 12: Cross-coupling of alkenes with oxime esters.
Scheme 13: Oxo-azidation of vinyl arenes.
Scheme 14: Azidation/difunctionalization of vinyl arenes.
Scheme 15: Photoinitiated copper-catalyzed Sonogashira reaction.
Scheme 16: Alkyne functionalization reactions.
Scheme 17: Alkynylation of dihydroquinoxalin-2-ones with terminal alkynes.
Scheme 18: Decarboxylative alkynylation of redox-active esters.
Scheme 19: Aerobic oxidative C(sp)–S coupling reaction.
Scheme 20: Copper-catalyzed alkylation of carbazoles with alkyl halides.
Scheme 21: C–N coupling of organic halides with amides and aliphatic amines.
Scheme 22: Copper-catalyzed C–X (N, S, O) bond formation reactions.
Scheme 23: Arylation of C(sp2)–H bonds of azoles.
Scheme 24: C–C cross-coupling of aryl halides and heteroarenes.
Scheme 25: Benzylic or α-amino C–H functionalization.
Scheme 26: α-Amino C–H functionalization of aromatic amines.
Scheme 27: C–H functionalization of aromatic amines.
Scheme 28: α-Amino-C–H and alkyl C–H functionalization reactions.
Scheme 29: Other copper-photocatalyzed reactions.
Scheme 30: Cross-coupling of oxime esters with phenols or amines.
Scheme 31: Alkylation of heteroarene N-oxides.
Beilstein J. Org. Chem. 2021, 17, 2302–2314, doi:10.3762/bjoc.17.148
Graphical Abstract
Figure 1: (I) DLS of PPM-NP4, MPM-NP2, PPM-NP4-TPP and MPM-NP2-TPP and (II) TEM of PPM-NP4-TPP and MPM-NP2-TPP...
Figure 2: Representative 31P NMR (top) and 1H NMR (bottom) spectrum of PP3-TPP conjugation product in D2O.
Scheme 1: Synthesis of TPP-based PISA particles based on zwitterionic 2-methacryloyloxyethyl phosphorylcholin...
Figure 3: Penetration of PPM-NP4-TPP and MPM-NP2-TPP micelles and fluorescence intensity profile on (A I, II)...
Figure 4: Growth effects of PPM-NP4-TPP and MPM-NP2-TPP on SW982 spheroids after 3 and 6 days of incubation (c...
Figure 5: Cell viability of SW982 spheroids after 6 days treatment with PPM-NP4, PPM-NP-TPP, MPM-NP2 and MPM-...
Figure 6: Cell localization of PPM-NP4-TPP (I) and MPM-NP2-TPP (II) into (A) mitochondria and (B) lysosomes u...
Figure 7: Cytotoxicity study of PPM-NP4-TPP and MPM-NP2-TPP on SW982 cells in relation to the concentration o...
Beilstein J. Org. Chem. 2021, 17, 2102–2122, doi:10.3762/bjoc.17.137
Graphical Abstract
Scheme 1: Synthesis of 2,2’-bis(indole)borinic ester 3.
Scheme 2: Synthesis of 2,2’-bisindole NHC·boranes by an SEAr mechanism.
Scheme 3: Syntheses of indolyl amines through Buchwald–Hartwig cross coupling.
Scheme 4: Synthesis of 3,3’-bis(indolyl) ethers.
Scheme 5: C–H silylation of indoles.
Scheme 6: n-BuLi-mediated syntheses of bis(indol-3-yl)silanes.
Scheme 7: Acid-catalyzed syntheses of bis(indol-3-yl)silanes and mechanisms.
Scheme 8: B(C6F5)3 and Al(C6F5)3-catalyzed syntheses of bis(indol-3-yl)silanes reported by Han.
Scheme 9: Base-mediated syntheses of bis and tris(indol-2-yl)phosphines.
Scheme 10: Synthesis of bis(indol-2-yl)sulfides using SL2-type reagents.
Scheme 11: Synthesis of 2,3’- and 2,2’-bis(indolyl)sulfides using disulfides as substrates.
Scheme 12: Synthesis of diindol-2-ylsulfide (84) from 2-iodoindole (92) and thiourea.
Scheme 13: Synthesis of bis(indol-3-yl)sulfides using N-silylated 3-bromoindole 93.
Scheme 14: Fischer indole synthesis of bis(indol-3-yl)sulfides using thio diketones.
Scheme 15: Oxidative synthesis of bis(indol-3-yl)sulfides using indoles and elemental sulfur.
Scheme 16: Synthesis of bis(indol-3-yl)sulfides using sulfoxides as sulfur source.
Scheme 17: Syntheses of bis(indol-2-yl)selanes.
Scheme 18: Syntheses of bis(indol-3-yl)selanes.
Scheme 19: Synthesis of bis(indol-2-yl)tellane 147.
Scheme 20: Synthesis of tris(indolyl)borane 154.
Scheme 21: Synthesis of bis(indol-4-yl)amines 159.
Scheme 22: Synthesis of bis(indol-5-yl)amines.
Scheme 23: Synthesis of 6,5’/6,6’-bis(indolyl)amines.
Scheme 24: Synthesis of potent HIV-inhibitors 6,6’-bis(indolyl) ethers.
Scheme 25: Synthesis of bis(indol-7-yl) ether.
Scheme 26: Synthesis of di(indol-5-yl)sulfide (183).
Scheme 27: Syntheses of 2,2’-diformyl-7,7’-bis(indolyl)selenides.
Beilstein J. Org. Chem. 2021, 17, 1814–1827, doi:10.3762/bjoc.17.124
Graphical Abstract
Figure 1: Schematic overview of fungal interactions in the environment. Fungi can be found in essentially all...
Figure 2: Fungal derived bioactive natural compounds with ecological and/or economic relevance.
Figure 3: Gliotoxin biosynthetic gene cluster and it major biosynthetic transformations: Gliotoxin (5) is the...
Figure 4: Amoebicidal secondary metabolites trypacidin and fumagillin of Aspergillus fumigatus.
Figure 5: Intermediates of the DHN-melanin biosynthesis in Aspergillus fumigatus.
Figure 6: Intermediates and products of the fumigaclavine C biosynthesis.
Figure 7: Bioactive secondary metabolites of Aspergillus fumigatus.
Figure 8: Helvolic acid gene cluster of A. fumigatus.
Beilstein J. Org. Chem. 2021, 17, 1641–1688, doi:10.3762/bjoc.17.116
Graphical Abstract
Figure 1: Structure of DNA and PNA.
Figure 2: PNA binding modes: (A) PNA–dsDNA 1:1 triplex; (B) PNA–DNA–PNA strand-invasion triplex; (C) the Hoog...
Figure 3: Structure of P-form PNA–DNA–PNA triplex from reference [41]. (A) view in the major groove and (B) view ...
Figure 4: Structures of backbone-modified PNA.
Figure 5: Structures of PNA having α- and γ-substituted backbones.
Figure 6: Structures of modified nucleobases in PNA to improve Hoogsteen hydrogen bonding to guanine and aden...
Figure 7: Proposed hydrogen bonding schemes for modified PNA nucleobases designed to recognize pyrimidines or...
Figure 8: Modified nucleobases to modulate Watson–Crick base pairing and chemically reactive crosslinking PNA...
Figure 9: Examples of triplets formed by Janus-wedge PNA nucleobases (blue). R1 denotes DNA, RNA, or PNA back...
Figure 10: Examples of fluorescent PNA nucleobases. R1 denotes DNA, RNA, or PNA backbones.
Figure 11: Endosomal entrapment and escape pathways of PNA and PNA conjugates.
Figure 12: (A) representative cell-penetrating peptides (CPPs), (B) conjugation designs and linker chemistries....
Figure 13: Proposed delivery mode by pHLIP-PNA conjugates (A) the transmembrane section of pHLIP interacting w...
Figure 14: Structures of modified penetratin CPP conjugates with PNA linked through either disulfide (for stud...
Figure 15: Chemical structure of C9–PNA, a stable amphipathic (cyclic-peptide)–PNA conjugate.
Figure 16: Structures of PNA conjugates with a lipophilic triphenylphosphonium cation (TPP–PNA) through (A) th...
Figure 17: Structures of (A) chloesteryl–PNA, (B) cholate–PNA and (C) cholate–PNA(cholate)3.
Figure 18: Structures of PNA–GalNAc conjugates (A) (GalNAc)2K, (B) triantennary (GalNAc)3, and (C) trivalent (...
Figure 19: Vitamin B12–PNA conjugates with different linkages.
Figure 20: Structures of (A) neomycin B, (B) PNA–neamine conjugate, and (C) PNA–neosamine conjugate.
Figure 21: PNA clamp (red) binding to target DNA containing a mixture of sequences (A) PNA binds with higher a...
Figure 22: Rolling circle amplification using PNA openers (red) to invade a dsDNA target forming a P-loop. A p...
Figure 23: Molecular beacons containing generic fluorophores (Fl) and quenchers (Q) recognizing a complementar...
Figure 24: (A) Light-up fluorophores such as thiazole orange display fluorescence enhancement upon binding to ...
Figure 25: Templated fluorogenic detection of oligonucleotides using two PNAs. (A) Templated FRET depends on h...
Figure 26: Lateral flow devices use a streptavidin labeled strip on nitrocellulose paper to anchor a capture P...
Beilstein J. Org. Chem. 2021, 17, 1181–1312, doi:10.3762/bjoc.17.90
Graphical Abstract
Figure 1: Representative shares of the global F&F market (2018) segmented on their applications [1].
Figure 2: General structure of an international fragrance company [2].
Figure 3: The Michael Edwards fragrance wheel.
Figure 4: Examples of oriental (1–3), woody (4–7), fresh (8–10), and floral (11 and 12) notes.
Figure 5: A basic depiction of batch vs flow.
Scheme 1: Examples of reactions for which flow processing outperforms batch.
Scheme 2: Some industrially important aldol-based transformations.
Scheme 3: Biphasic continuous aldol reactions of acetone and various aldehydes.
Scheme 4: Aldol synthesis of 43 in flow using LiHMDS as the base.
Scheme 5: A semi-continuous synthesis of doravirine (49) involving a key aldol reaction.
Scheme 6: Enantioselective aldol reaction using 5-(pyrrolidin-2-yl)tetrazole (51) as catalyst in a microreact...
Scheme 7: Gröger's example of asymmetric aldol reaction in aqueous media.
Figure 6: Immobilised reagent column reactor types.
Scheme 8: Photoinduced thiol–ene coupling preparation of silica-supported 5-(pyrrolidin-2-yl)tetrazole 63 and...
Scheme 9: Continuous-flow approach for enantioselective aldol reactions using the supported catalyst 67.
Scheme 10: Ötvös’ employment of a solid-supported peptide aldol catalyst in flow.
Scheme 11: The use of proline tetrazole packed in a column for aldol reaction between cyclohexanone (65) and 2...
Scheme 12: Schematic diagram of an aminosilane-grafted Si-Zr-Ti/PAI-HF reactor for continuous-flow aldol and n...
Scheme 13: Continuous-flow condensation for the synthesis of the intermediate 76 to nabumetone (77) and Microi...
Scheme 14: Synthesis of ψ-Ionone (80) in continuous-flow via aldol condensation between citral (79) and aceton...
Scheme 15: Synthesis of β-methyl-ionones (83) from citral (79) in flow. The steps are separately described, an...
Scheme 16: Continuous-flow synthesis of 85 from 84 described by Gavriilidis et al.
Scheme 17: Continuous-flow scCO2 apparatus for the synthesis of 2-methylpentanal (87) and the self-condensed u...
Scheme 18: Chen’s two-step flow synthesis of coumarin (90).
Scheme 19: Pechmann condensation for the synthesis of 7-hydroxyxcoumarin (93) in flow. The setup extended to c...
Scheme 20: Synthesis of the dihydrojasmonate 35 exploiting nitro derivative proposed by Ballini et al.
Scheme 21: Silica-supported amines as heterogeneous catalyst for nitroaldol condensation in flow.
Scheme 22: Flow apparatus for the nitroaldol condensation of p-hydroxybenzaldehyde (102) to nitrostyrene 103 a...
Scheme 23: Nitroaldol reaction of 64 to 105 employing a quaternary ammonium functionalised PANF.
Scheme 24: Enantioselective nitroaldol condensation for the synthesis of 108 under flow conditions.
Scheme 25: Enatioselective synthesis of 1,2-aminoalcohol 110 via a copper-catalysed nitroaldol condensation.
Scheme 26: Examples of Knoevenagel condensations applied for fragrance components.
Scheme 27: Flow apparatus for Knoevenagel condensation described in 1989 by Venturello et al.
Scheme 28: Knoevenagel reaction using a coated multichannel membrane microreactor.
Scheme 29: Continuous-flow apparatus for Knoevenagel condensation employing sugar cane bagasse as support deve...
Scheme 30: Knoevenagel reaction for the synthesis of 131–135 in flow using an amine-functionalised silica gel. ...
Scheme 31: Continuous-flow synthesis of compound 137, a key intermediate for the synthesis of pregabalin (138)...
Scheme 32: Continuous solvent-free apparatus applied for the synthesis of compounds 140–143 using a TSE. Throu...
Scheme 33: Lewis et al. developed a spinning disc reactor for Darzens condensation of 144 and a ketone to furn...
Scheme 34: Some key industrial applications of conjugate additions in the F&F industry.
Scheme 35: Continuous-flow synthesis of 4-(2-hydroxyethyl)thiomorpholine 1,1-dioxide (156) via double conjugat...
Scheme 36: Continuous-flow system for Michael addition using CsF on alumina as the catalyst.
Scheme 37: Calcium chloride-catalysed asymmetric Michael addition using an immobilised chiral ligand.
Scheme 38: Continuous multistep synthesis for the preparation of (R)-rolipram (173). Si-NH2: primary amine-fun...
Scheme 39: Continuous-flow Michael addition using ion exchange resin Amberlyst® A26.
Scheme 40: Preparation of the heterogeneous catalyst 181 developed by Paixão et al. exploiting Ugi multicompon...
Scheme 41: Continuous-flow system developed by the Paixão’s group for the preparation of Michael asymmetric ad...
Scheme 42: Continuous-flow synthesis of nitroaldols catalysed by supported catalyst 184 developed by Wennemers...
Scheme 43: Heterogenous polystyrene-supported catalysts developed by Pericàs and co-workers.
Scheme 44: PANF-supported pyrrolidine catalyst for the conjugate addition of cyclohexanone (65) and trans-β-ni...
Scheme 45: Synthesis of (−)-paroxetine precursor 195 developed by Ötvös, Pericàs, and Kappe.
Scheme 46: Continuous-flow approach for the 5-step synthesis of (−)-oseltamivir (201) as devised by Hayashi an...
Scheme 47: Continuous-flow enzyme-catalysed Michael addition.
Scheme 48: Continuous-flow copper-catalysed 1,4 conjugate addition of Grignard reagents to enones. Reprinted w...
Scheme 49: A collection of commonly encountered hydrogenation reactions.
Figure 7: The ThalesNano H-Cube® continuous-flow hydrogenator.
Scheme 50: Chemoselective reduction of an α,β-unsaturated ketone using the H-Cube® reactor.
Scheme 51: Incorporation of Lindlar’s catalyst into the H-Cube® reactor for the reduction of an alkyne.
Scheme 52: Continuous-flow semi-hydrogenation of alkyne 208 to 209 using SACs with H-Cube® system.
Figure 8: The standard setups for tube-in-tube gas–liquid reactor units.
Scheme 53: Homogeneous hydrogenation of olefins using a tube-in-tube reactor setup.
Scheme 54: Recyclable heterogeneous flow hydrogenation system.
Scheme 55: Leadbeater’s reverse tube-in-tube hydrogenation system for olefin reductions.
Scheme 56: a) Hydrogenation using a Pd-immobilised microchannel reactor (MCR) and b) a representation of the i...
Scheme 57: Hydrogenation of alkyne 238 exploiting segmented flow in a Pd-immobilised capillary reactor.
Scheme 58: Continuous hydrogenation system for the preparation of cyrene (241) from (−)-levoglucosenone (240).
Scheme 59: Continuous hydrogenation system based on CSMs developed by Hornung et al.
Scheme 60: Chemoselective reduction of carbonyls (ketones over aldehydes) in flow.
Scheme 61: Continuous system for the semi-hydrogenation of 256 and 258, developed by Galarneau et al.
Scheme 62: Continuous synthesis of biodiesel fuel 261 from lignin-derived furfural acetone (260).
Scheme 63: Continuous synthesis of γ-valerolacetone (263) via CTH developed by Pineda et al.
Scheme 64: Continuous hydrogenation of lignin-derived biomass (products 265, 266, and 267) using a sustainable...
Scheme 65: Ru/C or Rh/C-catalysed hydrogenation of arene in flow as developed by Sajiki et al.
Scheme 66: Polysilane-immobilized Rh–Pt-catalysed hydrogenation of arenes in flow by Kobayashi et al.
Scheme 67: High-pressure in-line mixing of H2 for the asymmetric reduction of 278 at pilot scale with a 73 L p...
Figure 9: Picture of the PFR employed at Eli Lilly & Co. for the continuous hydrogenation of 278 [287]. Reprinted ...
Scheme 68: Continuous-flow asymmetric hydrogenation using Oppolzer's sultam 280 as chiral auxiliary.
Scheme 69: Some examples of industrially important oxidation reactions in the F&F industry. CFL: compact fluor...
Scheme 70: Gold-catalysed heterogeneous oxidation of alcohols in flow.
Scheme 71: Uozumi’s ARP-Pt flow oxidation protocol.
Scheme 72: High-throughput screening of aldehyde oxidation in flow using an in-line GC.
Scheme 73: Permanganate-mediated Nef oxidation of nitroalkanes in flow with the use of in-line sonication to p...
Scheme 74: Continuous-flow aerobic anti-Markovnikov Wacker oxidation.
Scheme 75: Continuous-flow oxidation of 2-benzylpyridine (312) using air as the oxidant.
Scheme 76: Continuous-flow photo-oxygenation of monoterpenes.
Scheme 77: A tubular reactor design for flow photo-oxygenation.
Scheme 78: Glucose oxidase (GOx)-mediated continuous oxidation of glucose using compressed air and the FFMR re...
Scheme 79: Schematic continuous-flow sodium hypochlorite/TEMPO oxidation of alcohols.
Scheme 80: Oxidation using immobilised TEMPO (344) was developed by McQuade et al.
Scheme 81: General protocol for the bleach/catalytic TBAB oxidation of aldehydes and alcohols.
Scheme 82: Continuous-flow PTC-assisted oxidation using hydrogen peroxide. The process was easily scaled up by...
Scheme 83: Continuous-flow epoxidation of cyclohexene (348) and in situ preparation of m-CPBA.
Scheme 84: Continuous-flow epoxidation using DMDO as oxidant.
Scheme 85: Mukayama aerobic epoxidation optimised in flow mode by the Favre-Réguillon group.
Scheme 86: Continuous-flow asymmetric epoxidation of derivatives of 359 exploiting a biomimetic iron catalyst.
Scheme 87: Continuous-flow enzymatic epoxidation of alkenes developed by Watts et al.
Scheme 88: Engineered multichannel microreactor for continuous-flow ozonolysis of 366.
Scheme 89: Continuous-flow synthesis of the vitamin D precursor 368 using multichannel microreactors. MFC: mas...
Scheme 90: Continuous ozonolysis setup used by Kappe et al. for the synthesis of various substrates employing ...
Scheme 91: Continuous-flow apparatus for ozonolysis as developed by Ley et al.
Scheme 92: Continuous-flow ozonolysis for synthesis of vanillin (2) using a film-shear flow reactor.
Scheme 93: Examples of preparative methods for ajoene (386) and allicin (388).
Scheme 94: Continuous-flow oxidation of thioanisole (389) using styrene-based polymer-supported peroxytungstat...
Scheme 95: Continuous oxidation of thiosulfinates using Oxone®-packed reactor.
Scheme 96: Continuous-flow electrochemical oxidation of thioethers.
Scheme 97: Continuous-flow oxidation of 400 to cinnamophenone (235).
Scheme 98: Continuous-flow synthesis of dehydrated material 401 via oxidation of methyl dihydrojasmonate (33).
Scheme 99: Some industrially important transformations involving Grignard reagents.
Scheme 100: Grachev et al. apparatus for continuous preparation of Grignard reagents.
Scheme 101: Example of fluidized Mg bed reactor with NMR spectrometer as on-line monitoring system.
Scheme 102: Continuous-flow synthesis of Grignard reagents and subsequent quenching reaction.
Figure 10: Membrane-based, liquid–liquid separator with integrated pressure control [52]. Adapted with permission ...
Scheme 103: Continuous-flow synthesis of 458, an intermediate to fluconazole (459).
Scheme 104: Continuous-flow synthesis of ketones starting from benzoyl chlorides.
Scheme 105: A Grignard alkylation combining CSTR and PFR technologies with in-line infrared reaction monitoring....
Scheme 106: Continuous-flow preparation of 469 from Grignard addition of methylmagnesium bromide.
Scheme 107: Continuous-flow synthesis of Grignard reagents 471.
Scheme 108: Preparation of the Grignard reagent 471 using CSTR and the continuous process for synthesis of the ...
Scheme 109: Continuous process for carboxylation of Grignard reagents in flow using tube-in-tube technology.
Scheme 110: Continuous synthesis of propargylic alcohols via ethynyl-Grignard reagent.
Scheme 111: Silica-supported catalysed enantioselective arylation of aldehydes using Grignard reagents in flow ...
Scheme 112: Acid-catalysed rearrangement of citral and dehydrolinalool derivatives.
Scheme 113: Continuous stilbene isomerisation with continuous recycling of photoredox catalyst.
Scheme 114: Continuous-flow synthesis of compound 494 as developed by Ley et al.
Scheme 115: Selected industrial applications of DA reaction.
Scheme 116: Multistep flow synthesis of the spirocyclic structure 505 via employing DA cycloaddition.
Scheme 117: Continuous-flow DA reaction developed in a plater flow reactor for the preparation of the adduct 508...
Scheme 118: Continuous-flow DA reaction using a silica-supported imidazolidinone organocatalyst.
Scheme 119: Batch vs flow for the DA reaction of (cyclohexa-1,5-dien-1-yloxy)trimethylsilane (513) with acrylon...
Scheme 120: Continuous-flow DA reaction between 510 and 515 using a shell-core droplet system.
Scheme 121: Continuous-flow synthesis of bicyclic systems from benzyne precursors.
Scheme 122: Continuous-flow synthesis of bicyclic scaffolds 527 and 528 for further development of potential ph...
Scheme 123: Continuous-flow inverse-electron hetero-DA reaction to pyridine derivatives such as 531.
Scheme 124: Comparison between batch and flow for the synthesis of pyrimidinones 532–536 via retro-DA reaction ...
Scheme 125: Continuous-flow coupled with ultrasonic system for preparation of ʟ-ascorbic acid derivatives 539 d...
Scheme 126: Two-step continuous-flow synthesis of triazole 543.
Scheme 127: Continuous-flow preparation of triazoles via CuAAC employing 546-based heterogeneous catalyst.
Scheme 128: Continuous-flow synthesis of compounds 558 through A3-coupling and 560 via AgAAC both employing the...
Scheme 129: Continuous-flow photoinduced [2 + 2] cycloaddition for the preparation of bicyclic derivatives of 5...
Scheme 130: Continuous-flow [2 + 2] and [5 + 2] cycloaddition on large scale employing a flow reactor developed...
Scheme 131: Continuous-flow preparation of the tricyclic structures 573 and 574 starting from pyrrole 570 via [...
Scheme 132: Continuous-flow [2 + 2] photocyclization of cinnamates.
Scheme 133: Continuous-flow preparation of cyclobutane 580 on a 5-plates photoreactor.
Scheme 134: Continuous-flow [2 + 2] photocycloaddition under white LED lamp using heterogeneous PCN as photocat...
Figure 11: Picture of the parallel tube flow reactor (PTFR) "The Firefly" developed by Booker-Milburn et al. a...
Scheme 135: Continuous-flow acid-catalysed [2 + 2] cycloaddition between silyl enol ethers and acrylic esters.
Scheme 136: Continuous synthesis of lactam 602 using glass column reactors.
Scheme 137: In situ generation of ketenes for the Staudinger lactam synthesis developed by Ley and Hafner.
Scheme 138: Application of [2 + 2 + 2] cycloadditions in flow employed by Ley et al.
Scheme 139: Examples of FC reactions applied in F&F industry.
Scheme 140: Continuous-flow synthesis of ibuprofen developed by McQuade et al.
Scheme 141: The FC acylation step of Jamison’s three-step ibuprofen synthesis.
Scheme 142: Synthesis of naphthalene derivative 629 via FC acylation in microreactors.
Scheme 143: Flow system for rapid screening of catalysts and reaction conditions developed by Weber et al.
Scheme 144: Continuous-flow system developed by Buorne, Muller et al. for DSD optimisation of the FC acylation ...
Scheme 145: Continuous-flow FC acylation of alkynes to yield β-chlorovinyl ketones such as 638.
Scheme 146: Continuous-flow synthesis of tonalide (619) developed by Wang et al.
Scheme 147: Continuous-flow preparation of acylated arene such as 290 employing Zr4+-β-zeolite developed by Kob...
Scheme 148: Flow system applied on an Aza-FC reaction catalysed by the thiourea catalyst 648.
Scheme 149: Continuous hydroformylation in scCO2.
Scheme 150: Two-step flow synthesis of aldehyde 655 through a sequential Heck reaction and subsequent hydroform...
Scheme 151: Single-droplet (above) and continuous (below) flow reactors developed by Abolhasani et al. for the ...
Scheme 152: Continuous hydroformylation of 1-dodecene (655) using a PFR-CSTR system developed by Sundmacher et ...
Scheme 153: Continuous-flow synthesis of the aldehyde 660 developed by Eli Lilly & Co. [32]. Adapted with permissio...
Scheme 154: Continuous asymmetric hydroformylation employing heterogenous catalst supported on carbon-based sup...
Scheme 155: Examples of acetylation in F&F industry: synthesis of bornyl (S,R,S-664) and isobornyl (S,S,S-664) ...
Scheme 156: Continuous-flow preparation of bornyl acetate (S,R,S-664) employing the oscillating flow reactor.
Scheme 157: Continuous-flow synthesis of geranyl acetate (666) from acetylation of geraniol (343) developed by ...
Scheme 158: 12-Ttungstosilicic acid-supported silica monolith-catalysed acetylation in flow.
Scheme 159: Continuous-flow preparation of cyclopentenone 676.
Scheme 160: Two-stage synthesis of coumarin (90) via acetylation of salicylaldehyde (88).
Scheme 161: Intensification process for acetylation of 5-methoxytryptamine (677) to melatonin (678) developed b...
Scheme 162: Examples of macrocyclic musky odorants both natural (679–681) and synthetic (682 and 683).
Scheme 163: Flow setup combined with microwave for the synthesis of macrocycle 686 via RCM.
Scheme 164: Continuous synthesis of 2,5-dihydro-1H-pyrroles via ring-closing metathesis.
Scheme 165: Continuous-flow metathesis of 485 developed by Leadbeater et al.
Figure 12: Comparison between RCM performed using different routes for the preparation of 696. On the left the...
Scheme 166: Continuous-flow RCM of 697 employed the solid-supported catalyst 698 developed by Grela, Kirschning...
Scheme 167: Continuous-flow RORCM of cyclooctene employing the silica-absorbed catalyst 700.
Scheme 168: Continuous-flow self-metathesis of methyl oleate (703) employing SILP catalyst 704.
Scheme 169: Flow apparatus for the RCM of 697 using a nanofiltration membrane for the recovery and reuse of the...
Scheme 170: Comparison of loadings between RCMs performed with different routes for the synthesis of 709.
Beilstein J. Org. Chem. 2021, 17, 964–976, doi:10.3762/bjoc.17.78
Graphical Abstract
Scheme 1: Scope of glycosyl acceptors for glycosylation with pivaloyl-protected mannosyl fluoride α-1a in liq...
Scheme 2: Glycosylation of binucleophiles 7a,b in liquid SO2.
Scheme 3: Pivaloyl-protected glucosyl fluoride β-9 as a glycosyl donor in liquid SO2.
Scheme 4: Benzyl protected manno- and glucopyranosyl fluorides α-15 and 16 as glycosyl donors in liquid SO2. ...
Scheme 5: 2-Deoxy glycosyl fluoride α-19 as a glycosyl donor in liquid SO2.
Figure 1: Detection of the FSO2− species by 19F NMR (471 MHz, D2O).
Figure 2: Computational study of reaction mechanism α-11 + MeOH → α-13c in the presence of and in absence of ...
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. 2021, 17, 771–799, doi:10.3762/bjoc.17.67
Graphical Abstract
Scheme 1: The electron transfer process in EDA complexes.
Scheme 2: Synthesis of benzo[b]phosphorus oxide 3 initiated by an EDA complex.
Scheme 3: Mechanism of the synthesis of quinoxaline derivative 7.
Scheme 4: Synthesis of imidazole derivative 10 initiated by an EDA complex.
Scheme 5: Synthesis of sulfamoylation product 12 initiated by an EDA complex.
Scheme 6: Mechanism of the synthesis of sulfamoylation product 12.
Scheme 7: Synthesis of indole derivative 22 initiated by an EDA complex.
Scheme 8: Synthesis of perfluoroalkylated pyrimidines 26 initiated by an EDA complex.
Scheme 9: Synthesis of phenanthridine derivative 29 initiated by an EDA complex.
Scheme 10: Synthesis of cis-tetrahydroquinoline derivative 32 initiated by an EDA complex.
Scheme 11: Mechanism of the synthesis of cis-tetrahydroquinoline derivative 32.
Scheme 12: Synthesis of phenanthridine derivative 38 initiated by an EDA complex.
Scheme 13: Synthesis of spiropyrroline derivative 40 initiated by an EDA complex.
Scheme 14: Synthesis of benzothiazole derivative 43 initiated by an EDA complex.
Scheme 15: Synthesis of perfluoroalkyl-s-triazine derivative 45 initiated by an EDA complex.
Scheme 16: Synthesis of indoline derivative 47 initiated by an EDA complex.
Scheme 17: Mechanism of the synthesis of spirocyclic indoline derivative 47.
Scheme 18: Synthesis of cyclobutane product 50 initiated by an EDA complex.
Scheme 19: Mechanism of the synthesis of spirocyclic indoline derivative 50.
Scheme 20: Synthesis of 1,3-oxazolidine compound 59 initiated by an EDA complex.
Scheme 21: Synthesis of trifluoromethylated product 61 initiated by an EDA complex.
Scheme 22: Synthesis of indole alkylation product 64 initiated by an EDA complex.
Scheme 23: Synthesis of perfluoroalkylation product 67 initiated by an EDA complex.
Scheme 24: Synthesis of hydrotrifluoromethylated product 70 initiated by an EDA complex.
Scheme 25: Synthesis of β-trifluoromethylated alkyne product 71 initiated by an EDA complex.
Scheme 26: Mechanism of the synthesis of 2-phenylthiophene derivative 74.
Scheme 27: Synthesis of allylated product 80 initiated by an EDA complex.
Scheme 28: Synthesis of trifluoromethyl-substituted alkynyl product 84 initiated by an EDA complex.
Scheme 29: Synthesis of dearomatized fluoroalkylation product 86 initiated by an EDA complex.
Scheme 30: Mechanism of the synthesis of dearomatized fluoroalkylation product 86.
Scheme 31: Synthesis of C(sp3)–H allylation product 91 initiated by an EDA complex.
Scheme 32: Synthesis of perfluoroalkylation product 93 initiated by an EDA complex.
Scheme 33: Synthesis of spirocyclic indolene derivative 95 initiated by an EDA complex.
Scheme 34: Synthesis of perfluoroalkylation product 97 initiated by an EDA complex.
Scheme 35: Synthesis of alkylated indole derivative 100 initiated by an EDA complex.
Scheme 36: Mechanism of the synthesis of alkylated indole derivative 100.
Scheme 37: Synthesis of arylated oxidized indole derivative 108 initiated by an EDA complex.
Scheme 38: Synthesis of 4-ketoaldehyde derivative 111 initiated by an EDA complex.
Scheme 39: Mechanism of the synthesis of 4-ketoaldehyde derivative 111.
Scheme 40: Synthesis of perfluoroalkylated olefin 118 initiated by an EDA complex.
Scheme 41: Synthesis of alkylation product 121 initiated by an EDA complex.
Scheme 42: Synthesis of acylation product 123 initiated by an EDA complex.
Scheme 43: Mechanism of the synthesis of acylation product 123.
Scheme 44: Synthesis of trifluoromethylation product 126 initiated by an EDA complex.
Scheme 45: Synthesis of unnatural α-amino acid 129 initiated by an EDA complex.
Scheme 46: Synthesis of thioether derivative 132 initiated by an EDA complex.
Scheme 47: Synthesis of S-aryl dithiocarbamate product 135 initiated by an EDA complex.
Scheme 48: Mechanism of the synthesis of S-aryl dithiocarbamate product 135.
Scheme 49: Synthesis of thioether product 141 initiated by an EDA complex.
Scheme 50: Mechanism of the synthesis of borate product 144.
Scheme 51: Synthesis of boronation product 148 initiated by an EDA complex.
Scheme 52: Synthesis of boration product 151 initiated by an EDA complex.
Scheme 53: Synthesis of boronic acid ester derivative 154 initiated by an EDA complex.
Scheme 54: Synthesis of β-azide product 157 initiated by an EDA complex.
Scheme 55: Decarboxylation reaction initiated by an EDA complex.
Scheme 56: Synthesis of amidated product 162 initiated by an EDA complex.
Scheme 57: Synthesis of diethyl phenylphosphonate 165 initiated by an EDA complex.
Scheme 58: Mechanism of the synthesis of diethyl phenylphosphonate derivative 165.
Scheme 59: Synthesis of (Z)-2-iodovinyl phenyl ether 168 initiated by an EDA complex.
Scheme 60: Mechanism of the synthesis of (Z)-2-iodovinyl phenyl ether derivative 168.
Scheme 61: Dehalogenation reaction initiated by an EDA complex.