Search for "multistep" in Full Text gives 294 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
Beilstein J. Org. Chem. 2026, 22, 461–479, doi:10.3762/bjoc.22.34
Graphical Abstract
Figure 1: Natural products with various stereogenic axes.
Scheme 1: Iridium complex-catalyzed asymmetrical synthesis of axially chiral (a) teraryl compounds 3 [40] and (b)...
Scheme 2: Rhodium-catalyzed enantio- and diastereoselective cycloaddition of 1,2-bis(arylpropiolyl)benzenes w...
Scheme 3: Synthesis of remote double axially chiral phosphoric acids.
Scheme 4: Construction of chiral biaxial diphosphine ligand.
Scheme 5: Atroposelective synthesis of biaxially chiral 1,4-distyryl-2,3-naphthalene diols.
Scheme 6: H-Bond-enabled enantioselective synthesis of remote biaxially chiral amides mediated by the counter...
Scheme 7: Enantioselective synthesis of biaryl products with twofold chiral axes.
Scheme 8: Iridium-catalyzed C–H alkylation to obtain the distal biaxial atropisomers.
Scheme 9: Co/SPDO-catalyzed biaxial bridged terphenyl compounds.
Scheme 10: Atroposelective Co-catalyzed synthesis of pyridoindolones with two distinct C–N axes.
Scheme 11: NHC organocatalytic synthesis of fused 1,4-biaxial uracils with C–C and C–N chiral axes.
Scheme 12: Synthesis of the first biaxially chiral compound reported by Ito and co-workers [35].
Scheme 13: Synthesis of chiral homoaryl compounds by Suzuki–Miyaura coupling.
Scheme 14: Structurally complex APIs with multiple chiral axes.
Scheme 15: Synthesis of helicenes containing stereogenic axes.
Scheme 16: Chiral NHC–Pd complex-catalyzed Suzuki–Miyaura cross-coupling reaction for the synthesis of block-t...
Scheme 17: Highly enantioselective C–H arylation of heteroarenes.
Scheme 18: Synthesis of novel axially chiral N-arylcarbazole skeletons by the assembly of azidonaphthalenes an...
Scheme 19: Catalytic enantioselective synthesis of axially chiral polycyclic aromatic hydrocarbons.
Scheme 20: Catalytic synthesis of biaxial triphenylene block-transfer isomers.
Scheme 21: A Pd(II)-catalyzed trans-selective C–H alkenylation strategy through thioether-directed olefination....
Scheme 22: Synthesis of N-arylphthalimides from prochiral maleimides and NHC-activated dienolides.
Scheme 23: Ni-catalyzed synthesis of triaxially chiral polysubstituted naphthalene scaffolds.
Scheme 24: Enantioselective Ni-catalyzed Suzuki–Miyaura cross-coupling reaction.
Scheme 25: The stereoselective synthesis of axial chiral indole–quinoline systems.
Scheme 26: The synthesis of bisbenzofuran atropisomeric oligoarenes containing two distal C–C stereogenic axes....
Beilstein J. Org. Chem. 2026, 22, 399–415, doi:10.3762/bjoc.22.28
Graphical Abstract
Figure 1: General concept of building multifunctional calix[4]arenes by joining propargyl/2-azidoethyl and p-...
Scheme 1: Silylation of the calixarene propargyl ethers. Conditions: i) LiHMDS (HMDS + n-BuLi), TBSCl, THF, −...
Scheme 2: Nitration of calixarenes 6, 8–10. Conditions: i) HNO3 (fuming, 10 equiv per calixarene aromatic uni...
Figure 2: Parts of 1H,13C HMBC spectra of calixarenes 12 (a) and 13 (b) recorded in CDCl3 solutions at 600 MH...
Figure 3: Molecular structures of partially nitrated calixarene 16 (a) and exhaustively nitrated calixarene 15...
Scheme 3: Reduction of calixarenes 11, 15 and 17. Conditions: i) SnCl2·2H2O, HCl, EtOH, H2O, 70 °C, then KOH,...
Scheme 4: Protecting group replacement in propargylated p-aminocalix[4]arenes. Conditions: i) Boc2O, Et3N, di...
Scheme 5: Synthesis of 2-azidoethylated p-aminocalix[4]arenes. Conditions: i) HNO3 (fuming, 10 equiv per cali...
Scheme 6: Synthesis of triazolated p-aminocalix[4]arenes 37–39 from the propargylated calixarene precursors 24...
Scheme 7: Synthesis of triazolated p-aminocalix[4]arenes 40 and 41 from the 2-azidoethylated calixarene precu...
Scheme 8: Removal of Boc protection in calixarenes 37–41; (i) CF3CO2H, dichloromethane, rt, then NaHCO3/H2O.
Scheme 9: Synthesis of triazolated tetraureacalix[4]arenes 47–51. Conditions: (i) p-tolyl isocyanate, toluene...
Figure 4: Planar and energy-minimized structures (with CHCl3 molecule included and triazole groups highlighte...
Figure 5: Planar structures of homodimers 482, 512, and heterodimer 48·52 (a); fragment of the 1H NMR spectru...
Figure 6: Planar structures of homodimers 472, 502, and heterodimer 47·52 (a); fragment of the 1H NMR spectru...
Beilstein J. Org. Chem. 2026, 22, 372–382, doi:10.3762/bjoc.22.25
Graphical Abstract
Scheme 1: Recent examples of hetero[8]helicenes: (A) symmetric hetero[8]helicenes; (B) unsymmetrical hetero[8...
Scheme 2: Short-step synthesis of unsymmetrical oxaza[8]helicenes 5.
Figure 1: A plausible reaction mechanism: cyclic voltammetry (CV) analyses of hydroxycarbazole derivative 3 a...
Figure 2: Aromaticity of oxaza[8]helicenes: (A) NICS(0)zz and NICS(1)zz values of 5a and 5b calculated at MN1...
Figure 3: (P/M) Enantiomerization process of 5a (A), 5b (B), 6a (C), and 6b (D); relative Gibbs free energies...
Figure 4: Photophysical characters of oxaza[n]helicenes: (A) and (B) UV–vis absorption and PL spectra; (C) Fr...
Figure 5: Chiroptical properties of oxaza[n]helicenes: (A) CD spectra measured in chloroform (1 × 10−5 M); CP...
Beilstein J. Org. Chem. 2026, 22, 352–369, doi:10.3762/bjoc.22.23
Graphical Abstract
Scheme 1: a) Resonance structure of amide. b) Concept of twisted amides. c) Transition-metal-catalyzed activa...
Scheme 2: Esterification of amides catalyzed by CeO2.
Scheme 3: Hydrolysis of amides catalyzed by Nb2O5.
Scheme 4: Manganese-catalyzed esterification of tertiary amides.
Scheme 5: Tungsten-catalyzed transamidation of hindered tertiary amides.
Scheme 6: Palladium-catalyzed transamidation of amides.
Scheme 7: Synthesis of benzyl esters via electrophilic activation of amides using DPT-BM.
Scheme 8: Esterification of amides promoted by SO2F2.
Scheme 9: α-Fluorinative cleavage of pyrrolidine-based tertiary amides via double electrophilic activation wi...
Scheme 10: Esterification of primary amides using TCCA via the generation of RCONCl2.
Scheme 11: Esterification of amides via electrophilic activation with Me2SO4.
Scheme 12: HBF4-mediated esterification of amides.
Scheme 13: Synthesis of 2,2,2-trifluoroethyl esters via electrophilic esterification of amide promoted by 67.
Scheme 14: Electrochemical activation of C–N bonds for esterification.
Scheme 15: Catalyst- and reagent-free transamidation of amide using aniline hydrochloride salt.
Scheme 16: CO2-catalyzed transamidation of amides.
Scheme 17: Transamidation of formamides using cyclic dihydrogen tetrametaphosphate.
Scheme 18: BF3·OEt2-mediated transamidation of primary amides.
Scheme 19: Acyl iodide intermediate 121 generation from amides for the transamidation using HOTf and KI.
Scheme 20: Esterification of N,N-dimethyl amides via electrophilic generation of acyl iodide intermediates.
Scheme 21: Transamidation of DMAc promoted by KOt-Bu.
Scheme 22: a) LiHMDS-mediated transamidation of tertiary amides. b) Computed reactivities of selected amides. ...
Scheme 23: Zn-catalyzed chemoselective cleavage of amides directed by tert-butyl nicotinate.
Scheme 24: Chemoselective cleavage of N-PMB anilide for transamidation via acyl fluoride 194 generation. a) Cu...
Beilstein J. Org. Chem. 2026, 22, 289–343, doi:10.3762/bjoc.22.21
Graphical Abstract
Scheme 1: Mechanistic overview of enzymes involved in ring-size-altering reactions: A: Difference in ionisati...
Scheme 2: A: Ring contraction through involvement of carbocationic intermediates in thujane monoterpene biosy...
Scheme 3: Examples of concerted ring expansions of carbocation intermediates in PxaTPS8-catalysed cyclisation...
Scheme 4: Sequential ring expansions during astellifadiene (17) synthesis reported by Abe and co-workers.
Scheme 5: Cyclobutane ring expansion and sequential ring contractions catalysed by the synthase AITS in the b...
Scheme 6: Ring expansion and transannular ring contraction of a cyclopentane to cyclobutane in the biosynthes...
Scheme 7: Computationally elucidated concerted cyclisations/alkyl/hydride shifts during the biosynthesis of t...
Scheme 8: Cyclisation events and 6→5-ring contraction during the construction of epi-isozizaene (26) catalyse...
Scheme 9: Transannular cyclisations and 4→5-membered ring expansion through dyotropic 1,2-rearrangement of al...
Scheme 10: Ring expansion in presilphiperfolan-8b-ol (31) biosynthesis and ring contraction of the presilphipe...
Scheme 11: Ring contraction via transannular cyclopropanation and opening of cyclopropane in the biosynthesis ...
Scheme 12: The crucial CYP450-catalysed oxidative rearrangement defining the skeleton in gibberellin biosynthe...
Scheme 13: CYP450-mediated oxidation of cyclopentane methylene expanding the 8-membered ring in the biosynthes...
Scheme 14: CYP450-mediated oxidation of an exocyclic methyl group to effect transannular cyclisation across th...
Scheme 15: Non-enzymatic transannular aldol reaction enables the formation of the 5/13/3-tricyclic ring system...
Scheme 16: A: Oxidative ring expansion of a cyclopentane by incorporation of a methyl group in the biosynthesi...
Scheme 17: Rearrangement and ring expansion in the construction of the complex bridged carbon framework of and...
Scheme 18: Ketoglutarate-mediated oxidations of preaustinoid A1 (53) en route to complex meroterpenoids, B-rin...
Scheme 19: Proposed putative biosynthetic formation of the tigliane skeleton from an E,E,Z-triene.
Scheme 20: Photocatalytic tandem ring expansion/contraction of santonin to give photosantonin products and gua...
Scheme 21: A: Proposed biosynthesis of stelleroid B (66) from stelleranoid I (65) by ketol rearrangement; B: o...
Scheme 22: Singular examples of A,B-ring contractions and expansions in the biosynthesis of sesquiterpenoids e...
Scheme 23: A: plausible proposed biosynthetic pathway for the tigliane/ingenane skeletal rearrangement and 1,2...
Scheme 24: A: Multiple ring-size alterations during xenovulene A (90) biosynthesis; B: Ring contraction and re...
Scheme 25: Proposed biosyntheses of the complex, polycyclic terpenoid illisimonin A (97) and the bridged antro...
Scheme 26: Proposed biogenetic origin for the meroterpenoid liphagal (104) via epoxide-mediated ring expansion....
Scheme 27: Proposed biogenetic origin for the ring-contracted members of the taiwaniaquinol family.
Scheme 28: A: Schenck ene/Hock/Aldol cascade effecting B-ring contraction in atheronal B (113); B: Selective C...
Scheme 29: A: D-ring expansion of buxenone (118) via cyclopropanation towards buxaustroine A (119); B: Propose...
Scheme 30: Biosynthetic origin of alstoscholarinoids A (124) and B (125) via cascade oxidative rearrangement c...
Scheme 31: Biogenetic origin of the hedgehog signalling inhibitor cyclopamine (129) by tandem ring contraction...
Scheme 32: Proposed biogenetic origin of the B-ring contracted spirocyclic triterpenoid spirochensilide A (131...
Scheme 33: A: Proposed B-ring contraction during the biosynthesis of holophyllane A (133); B: B-ring contracti...
Scheme 34: Radical and ionic/polar mechanisms for the C-ring-contracted triterpenoids phomopsterone B (139) an...
Scheme 35: A: Plausible mechanism for the formation of schiglautone A (144) from anwuweizic acid (145); B: Pro...
Scheme 36: Reported biosynthetic proposal for the formation of B-ring expanded triterpenoids rhodoterpenoids A...
Scheme 37: A: Final reaction step in the synthesis of euphorikanin A (154), benzilic acid-type ring contractio...
Scheme 38: Tricyclic ring expansion in the Gui synthesis of gibbosterol A (158) and sarocladione (160) via Ru-...
Scheme 39: A: A-ring expansion during the Gui synthesis of rubriflordilactone B (161); B: Mechanism for the bi...
Scheme 40: Photosantonin rearrangement effects A/B ring contraction/expansion in Li’s synthesis of the complex...
Scheme 41: Tandem A/B ring expansion/contraction of an ergosterol derivative via pinacol rearrangement in the ...
Scheme 42: Synthetic studies towards cyclocitrinol (179) by A) the semisynthetic approach by Gui et al. using ...
Scheme 43: A: Bioinspired synthesis of spirochensilide A (131) by the Heretsch group via selective 8,9-epoxida...
Scheme 44: Baran’s synthesis of cortistatin A (191), expanding the B-ring through a cyclopropane fragmentation....
Scheme 45: Ding’s total synthesis of retigeranic acid (198) showcasing sequential 6→5 ring contractions.
Scheme 46: A: Oxa-di-π-methane (ODPM) rearrangement of a bicyclic ketone en route to silphiperfolenone (203); ...
Scheme 47: Biomimetic synthesis of liphagal (104) from sclareolide (221) by George and co-workers.
Scheme 48: Wu’s bioinspired synthesis of cucurbalsaminones B (224) and C (225) by photocatalytic oxa-di-π-meth...
Scheme 49: Baran’s total synthesis of maoecrystal V (230) featuring a pinacol rearrangement for ring expansion...
Scheme 50: A: Ketol rearrangement leading to ring contraction in the total synthesis of preaustinoid B; B: Ben...
Scheme 51: A: Scheidt’s synthesis of isovelleral (251) by pinacol rearrangement triggered by Mitsunobu conditi...
Scheme 52: Biomimetic transformations of simplified test substrates related to Euphorbia diterpenoids.
Scheme 53: A: First generation synthesis of taiwaniaquinones by benzilic acid-type rearrangement of the B-ring...
Scheme 54: A: Norrish type 1 radical recombination leading to ring contraction en route to cuparenone (272): 1...
Scheme 55: Ring contraction of a bridged D-ring system in the total synthesis of andrastatin D (280), terrenoi...
Scheme 56: Biomimetic synthesis of hyperjapone A (284) and hyperjaponol C (285) by George et al.
Scheme 57: Heretsch’ synthesis of dankastarones A (288) and B (289), swinhoeisterol A (290), and periconiaston...
Scheme 58: A: Zhang’s ring contraction during the synthesis of stemar-13-ene (295) by pinacol rearrangement; B...
Scheme 59: Trauner’s biomimetic synthesis of preuisolactone A (307) featuring a ring contraction via benzilic ...
Scheme 60: Bioinspired approaches for ring contraction/expansion reactions in the synthesis of alstoscholarino...
Scheme 61: A: Sarpong and Li, Wang and co-workers’ ring expansion of cephanolide A (313) to reach harringtonol...
Beilstein J. Org. Chem. 2026, 22, 257–273, doi:10.3762/bjoc.22.19
Graphical Abstract
Figure 1: Aromatic molecules as the foundation of modern molecular chemistry.
Figure 2: Arenes as springboards to three-dimensional chemical space and strategies toward arene activation v...
Figure 3: Structure and synthetic utilization of strained arenes; NICS: nucleus independent chemical shifts [26-28].
Figure 4: Bonding and reactivity of η2-coordinated aromatic systems [44,46].
Figure 5: Illustrative selection of η2-coordinating dearomatization agents; MeIm: N-methylimidazole, NHE: nor...
Figure 6: Preparation, lability and most stable linkage isomers of pentaammineosmium(II) complexes.
Scheme 1: Heteroatom-directed reactions of η2-arene complexes [45,50].
Figure 7: Latent functionality through transient metal binding.
Figure 8: Selective hydrogenation of η2-coordinated benzene to cyclohexene under ambient conditions [53,54].
Scheme 2: Synthesis and utilization of enantioenrichted Mo(η2-arene) complexes in enantioselective synthesis [55]....
Scheme 3: Synthesis of trisubstituted cyclohexenes from phenyl sulfones enabled by tungsten-mediated dearomat...
Scheme 4: Diels–Alder reactions of η2-arene complexes with alkenes and alkynes; NMM: N-methylmaleimide [64,65].
Scheme 5: Binding characteristics and pioneering examples of isolable η3-benzyl complexes.
Figure 9: Divergent functionalization of benzyl electrophiles leveraging η3-benzyl complexes toward benzylic ...
Scheme 6: p-Selective allylation of benzyl chlorides with allylstannanes and subsequent synthetic expansion o...
Figure 10: Strategies for para- and ortho-selective arene functionalization/dearomatization via η3-benzyl comp...
Scheme 7: Substrate-dependent ortho- and para-selective dearomatization of naphthyl chlorides and leveraging ...
Figure 11: η4-Arene coordination as an underexplored but promising pathway for arene activation [96,98-100].
Beilstein J. Org. Chem. 2025, 21, 2479–2488, doi:10.3762/bjoc.21.190
Graphical Abstract
Scheme 1: (a) Representative examples of bioactive nitrocarbazoles. (b) Traditional electrophilic aromatic su...
Figure 1: ORTEP diagram of compound 2a (CCDC 2478298).
Scheme 2: Effect of directing groups on the nitration of the carbazoles.
Scheme 3: Scope of the method. Reaction conditions: 1 (0.2 mmol, 1.0 equiv), Pd2(dba)3 (0.02 mmol, 10 mol %),...
Scheme 4: Gram-scale synthesis, directing group removal, and synthetic utility of our method.
Scheme 5: Key mechanistic studies.
Figure 2: Plausible catalytic cycle.
Beilstein J. Org. Chem. 2025, 21, 2389–2415, doi:10.3762/bjoc.21.184
Graphical Abstract
Figure 1: Versatile compounds via cycloaddition reactions.
Scheme 1: Molecular structures of parent compounds 1a–f, 2a–d and cycloadducts 3a–u.
Figure 2: a) Radar view of the physical properties of methyl laurate. b) Oral toxicity values of methyl laura...
Figure 3: The oral toxicity values of all the solvents utilized in the present study obtained with ProTox 3.0....
Figure 4: Ecological, environmental risk assessments, pesticide similarity and biodegradability assessments o...
Figure 5: Ecological, environmental risk assessments, pesticide similarity and biodegradability assessments o...
Figure 6: Ecological, environmental risk assessments, pesticide similarity and biodegradability assessments o...
Figure 7: Various toxicity parameters of methyl laurate and a series of other solvents calculated by ADMETLab...
Figure 8: a) Visualization of the localization of conventional organic and bio-based solvents in the Hansen s...
Figure 9: Vapour pressures of the solvents used (values retrieved from the Chemeo molecular database).
Scheme 2: Endo and exo stereoisomeric approaches of nitrone 1a and maleimide 2a in [3 + 2] cycloaddition reac...
Figure 10: Signals of protons used in the calculation of the diastereomeric ratios (cis/trans) of cycloadditio...
Figure 11: Results of studies on the recovery of solvents used in the reaction.
Figure 12: Simplified scheme describing the reaction monitoring and solvent recovery.
Figure 13: a) The superimposed spectra of C,N-diphenylnitrone and N-phenylmaleimide. b) The spectrum of methyl...
Beilstein J. Org. Chem. 2025, 21, 2260–2282, doi:10.3762/bjoc.21.173
Graphical Abstract
Scheme 1: Economical synthesis and pathway economy.
Scheme 2: Au(I)-catalyzed cascade cyclization paths of 1,5-enynes.
Scheme 3: Au(I)-catalyzed cyclization paths of 1,7-enynes.
Scheme 4: I2/TBHP-mediated radical cycloisomerization paths of 1,n-enyne.
Scheme 5: Au(I)-catalyzed cycloisomerization paths of 3-allyloxy-1,6-diynes.
Scheme 6: Pd(II)-catalyzed cycloisomerization paths of 2-alkynylbenzoate-cyclohexadienone.
Scheme 7: Stereoselective cyclization of 1,5-enynes.
Scheme 8: Substituent-controlled cycloisomerization of propargyl vinyl ethers.
Scheme 9: Au(I)-catalyzed pathway-controlled domino cyclization of 1,2-diphenylethynes.
Scheme 10: Au(I)-catalyzed tandem cyclo-isomerization of tryptamine-N-ethynylpropiolamide.
Scheme 11: Au(I)-catalyzed tunable cyclization of 1,6-cyclohexenylalkyne.
Scheme 12: Substituent-controlled 7-exo- and 8-endo-dig-selective cyclization of 2-propargylaminobiphenyl deri...
Scheme 13: BiCl3-catalyzed cycloisomerization of tryptamine-ynamide derivatives.
Scheme 14: Au(I)-mediated substituent-controlled cycloisomerization of 1,6-enynes.
Scheme 15: Ligand-controlled regioselective cyclization of 1,6-enynes.
Scheme 16: Ligand-dependent cycloisomerization of 1,7-enyne esters.
Scheme 17: Ligand-controlled cycloisomerization of 1,5-enynes.
Scheme 18: Ligand-controlled cyclization strategy of alkynylamide tethered alkylidenecyclopropanes.
Scheme 19: Ag(I)-mediated pathway-controlled cycloisomerization of tryptamine-ynamides.
Scheme 20: Gold-catalyzed cycloisomerization of indoles with alkynes.
Scheme 21: Catalyst-dependent cycloisomerization of dienol silyl ethers.
Scheme 22: Cycloisomerization of aromatic enynes governed by catalyst.
Scheme 23: Catalyst-dependent 1,2-migration in cyclization of 1-(indol-2-yl)-3-alkyn-1-ols.
Scheme 24: Gold-catalyzed cycloisomerization of N-propargyl-N-vinyl sulfonamides.
Scheme 25: Gold(I)-mediated enantioselective cycloisomerizations of ortho-(alkynyl)styrenes.
Scheme 26: Catalyst-controlled intramolecular cyclization of 1,7-enynes.
Scheme 27: Brønsted acid-catalyzed cycloisomerizations of tryptamine ynamides.
Scheme 28: Catalyst-controlled cyclization of indolyl homopropargyl amides.
Scheme 29: Angle strain-dominated 6-endo-trig cyclization of propargyl vinyl ethers.
Scheme 30: Angle strain-controlled cycloisomerization of alkyn-tethered indoles.
Scheme 31: Geometrical isomeration-dependent cycloisomerization of 1,3-dien-5-ynes.
Scheme 32: Temperature-controlled cyclization of 1,7-enynes.
Scheme 33: Cycloisomerizations of n-(o-ethynylaryl)acrylamides through temperature modulation.
Scheme 34: Temperature-controlled boracyclization of biphenyl-embedded 1,3,5-trien-7-ynes.
Beilstein J. Org. Chem. 2025, 21, 2234–2242, doi:10.3762/bjoc.21.170
Graphical Abstract
Figure 1: General overview of azobenzene chemistry. a) Selected examples and photoisomerization of azobenzene...
Scheme 1: Scope of aryl bromides in palladium-catalyzed dehydrogenative C–N coupling with phenylhydrazine (1a...
Scheme 2: Scope of arylhydrazines in palladium-catalyzed dehydrogenative C–N coupling with 2-bromotoluene (2a...
Scheme 3: Application to the synthesis of tetra-, tri or di-ortho-substituted azobenzenes via palladium-catal...
Figure 2: a) Proposed catalytic cycle for the one-pot palladium-catalyzed dehydrogenative C–N coupling for th...
Beilstein J. Org. Chem. 2025, 21, 2103–2172, doi:10.3762/bjoc.21.165
Graphical Abstract
Figure 1: C2–C6 biobased carbonyl building blocks.
Scheme 1: Proposed (2 + 2) route to glycolaldehyde and glycolic acid from erythritol by Cu/AC catalyst (AC = ...
Scheme 2: Reductive amination of GCA.
Scheme 3: N-Formylation of secondary amines by reaction with GCA.
Scheme 4: Synthesis and conversion of hydroxy acetals to cyclic acetals.
Scheme 5: Synthesis of 3-(indol-3-yl)-2,3-dihydrofurans via three-component reaction of glycolaldehyde, indol...
Scheme 6: BiCl3-catalyzed synthesis of benzo[a]carbazoles from 2-arylindoles and α-bromoacetaldehyde ethylene...
Scheme 7: Cu/NCNSs-based conversion of glycerol to glycolic acid and other short biobased acids.
Scheme 8: E. coli-based biotransformation of C1 source molecules (CH4, CO2 and CO) towards C2 glycolic acid.
Scheme 9: N-Formylation of amines with C2 (a) or C3 (b) biomass-based feedstocks.
Scheme 10: Methods for the formation of propanoic acid (PA) from lactic acid (LA).
Scheme 11: Co-polymerization of biobased lactic acid and glycolic acid via a bicatalytic process.
Scheme 12: Oxidation of α-hydroxy acids by tetrachloroaurate(III) in acetic acid–sodium acetate buffer medium.
Figure 2: Selective catalytic pathways for the conversion of lactic acid (LA).
Scheme 13: Synthesis of 1,3-PDO via cross-aldol reaction between formaldehyde and acetaldehyde to 3-hydroxypro...
Scheme 14: Hydrothermal conversion of 1,3-dihydroxy-2-propane and 2,3-dihydroxypropanal to methylglyoxal.
Scheme 15: FLS-catalyzed formose reaction to synthesize GA and DHA.
Scheme 16: GCA and DHA oxidation products of glycerol and isomerization of GCA to DHA under flow conditions us...
Scheme 17: Acid-catalyzed reactions of DHA with alcohols.
Scheme 18: Synthesis of dihydroxyacetone phosphate from dihydroxyacetone.
Scheme 19: Bifunctional acid–base catalyst DHA conversion into lactic acid via pyruvaldehyde or fructose forma...
Scheme 20: Catalytic one-pot synthesis of GA and co-synthesis of formamides and formates from DHA.
Scheme 21: (a) Synthesis of furan derivatives and (b) synthesis of thiophene derivative by cascade [3 + 2] ann...
Scheme 22: Brønsted acidic ionic liquid catalyzed synthesis of benzo[a]carbazole from renewable acetol and 2-p...
Scheme 23: Asymmetric hydrogenation of α-hydroxy ketones to 1,2-diols.
Scheme 24: Synthesis of novel 6-(substituted benzylidene)-2-methylthiazolo [2,3-b]oxazol-5(6H)-one from 1-hydr...
Scheme 25: ʟ-Proline-catalyzed synthesis of anti-diols from hydroxyacetone and aldehydes.
Scheme 26: C–C-bond-formation reactions of a biomass-based feedstock aromatic aldehyde (C5) and hydroxyacetone...
Scheme 27: Ethanol upgrading to C4 bulk chemicals via the thiamine (VB1)-catalyzed acetoin condensation.
Scheme 28: One-pot sequential chemoenzymatic synthesis of 2-aminobutane-1,4-diol and 1,2,4-butanetriol via 1,4...
Scheme 29: Synthesis of 1,4-dihydroxybutan-2-one by microbial transformation.
Scheme 30: Conversion of polyols by [neocuproine)Pd(OAc)]2(OTf)2] to α-hydroxy ketones.
Scheme 31: Chemoselective oxidation of alcohols with chiral palladium-based catalyst 2.
Scheme 32: Electrochemical transformation of furfural to 5-hydroxy-2(5H)-furanone (HFO).
Scheme 33: Selective hydrodeoxygenation of HFO and oxidation to γ-butyrolactone (GBL).
Scheme 34: Photosensitized oxygenation of furan towards HFO via ozonide intermediates.
Scheme 35: Conversion of furfural to HFO and MAN by using mesoporous carbon nitride (SGCN) as photocatalyst.
Scheme 36: Synthesis of HFO from furan derivatives.
Scheme 37: Photooxidation of furfural to 5-hydroxy-2(5H)-furanone (HFO).
Scheme 38: Synthesis of Friedel–Crafts indole adduct from HFO.
Scheme 39: Conversion of HFO to α,γ-substituted chiral γ-lactones.
Scheme 40: Tautomeric transformation of HFO to formylacrylic acid.
Scheme 41: Hydrolysis of HFO to succinic acid in aqueous solution.
Scheme 42: Substitution and condensation reactions of 5-hydroxy-2(5H)-furanone (HFO).
Scheme 43: (a) Conversion of HFO towards valuable C4 chemicals and (b) anodic oxidation of 5-hydroxy-2(5H)-fur...
Figure 3: Conversion of HFO towards other natural and synthetic substances.
Scheme 44: Conversion of furfural to maleic anhydride (reaction a: VOx/Al2O3; reaction b: VPO).
Scheme 45: Conversion of furfural into succinic acid.
Scheme 46: Electro‑, photo‑, and biocatalysis for one-pot selective conversions of furfural into C4 chemicals.
Scheme 47: Production route of furfural from hemicellulose.
Scheme 48: Mechanism for xylose dehydration to furfural through a choline xyloside intermediate.
Scheme 49: Conversion of furfural to furfuryl alcohol and its derivatives.
Scheme 50: Conversion of furfural to furfuryl alcohol and 3-(2-furyl)acrolein.
Scheme 51: The aerobic oxidative condensation of biomass-derived furfural and linear alcohols.
Scheme 52: The single-step synthesis of 2-pentanone from furfural.
Scheme 53: Electrocatalytic coupling reaction of furfural and levulinic acid.
Scheme 54: Conversion of furfural to m-xylylenediamine.
Scheme 55: Conversion of furfural to tetrahydrofuran-derived amines.
Scheme 56: Formation of trans-4,5-diamino-cyclopent-2-enones from furfural.
Scheme 57: Production of pyrrole and proline from furfural.
Scheme 58: Synthesis of 1‑(trifluoromethyl)-8-oxabicyclo[3.2.1]oct-3-en-2-ones from furfural.
Scheme 59: Conversion of furfural to furfural-derived diacids.
Scheme 60: A telescope protocol derived from furfural and glycerol.
Scheme 61: A tandem cyclization of furfural and 5,5-dimethyl-1,3-cyclohexanedione.
Scheme 62: A Ugi four-component reaction to construct furfural-based polyamides.
Scheme 63: One-pot synthesis of γ-acyloxy-Cy7 from furfural.
Scheme 64: Dimerization–Piancatelli sequence toward humins precursors from furfural.
Scheme 65: Conversion of furfural to CPN.
Scheme 66: Synthesis of jet fuels range cycloalkanes from CPN and lignin-derived vanillin.
Scheme 67: Solar-energy-driven synthesis of high-density biofuels from CPN.
Scheme 68: Reductive amination of CPN to cyclopentylamine.
Scheme 69: Asymmetric hydrogenation of C=O bonds of exocyclic α,β-unsaturated cyclopentanones.
Scheme 70: Preparation of levulinic acid via the C5 route (route a) or C6 route (routes b1 and b2).
Scheme 71: Mechanism of the rehydration of HMF to levulinic acid and formic acid.
Scheme 72: Important levulinic acid-derived chemicals.
Scheme 73: Direct conversion of levulinic acid to pentanoic acid.
Scheme 74: Catalytic aerobic oxidation of levulinic acid to citramalic acid.
Scheme 75: Conversion of levulinic acid to 1,4-pentanediol (a) see ref. [236]; b) see ref. [237]; c) see ref. [238]; d) see r...
Scheme 76: Selective production of 2-butanol through hydrogenolysis of levulinic acid.
Scheme 77: General reaction pathways proposed for the formation of 5MPs from levulinic acid.
Scheme 78: Selective reductive amination of levulinic acid to N-substituted pyrroles.
Scheme 79: Reductive amination of levulinic acid to chiral pyrrolidinone.
Scheme 80: Reductive amination of levulinic acid to non-natural chiral γ-amino acid.
Scheme 81: Nitrogen-containing chemicals derived from levulinic acid.
Scheme 82: Preparation of GVL from levulinic acid by dehydration and hydrogenation.
Scheme 83: Ruthenium-catalyzed levulinic acid to chiral γ-valerolactone.
Scheme 84: Catalytic asymmetric hydrogenation of levulinic acid to chiral GVL.
Scheme 85: Three steps synthesis of ε-caprolactam from GVL.
Scheme 86: Multistep synthesis of nylon 6,6 from GVL.
Scheme 87: Preparation of MeGVL by α-alkylation of GVL.
Scheme 88: Ring-opening polymerization of five-membered lactones.
Scheme 89: Synthesis of GVL-based ionic liquids.
Scheme 90: Preparation of butene isomers from GVL under Lewis acid conditions.
Scheme 91: Construction of C5–C12 fuels from GVL over nano-HZSM-5 catalysts.
Scheme 92: Preparation of alkyl valerate from GVL via ring opening/reduction/esterification sequence.
Scheme 93: Construction of 4-acyloxypentanoic acids from GVL.
Scheme 94: Synthesis of 1,4-pentanediol (PDO) from GVL.
Scheme 95: Construction of novel cyclic hemiketal platforms via self-Claisen condensation of GVL.
Scheme 96: Copper-catalyzed lactamization of GVL.
Figure 4: Main scaffolds obtained from HMF.
Scheme 97: Biginelli reactions towards HMF-containing dihydropyrimidinones.
Scheme 98: Hantzsch dihydropyridine synthesis involving HMF.
Scheme 99: The Kabachnik–Fields reaction involving HMF.
Scheme 100: Construction of oxazolidinone from HMF.
Scheme 101: Construction of rhodamine-furan hybrids from HMF.
Scheme 102: A Groebke–Blackburn–Bienaymé reaction involving HMF.
Scheme 103: HMF-containing benzodiazepines by [4 + 2 + 1] cycloadditions.
Scheme 104: Synthesis of fluorinated analogues of α-aryl ketones.
Scheme 105: Synthesis of HMF derived disubstituted γ-butyrolactone.
Scheme 106: Functionalized aromatics from furfural and HMF.
Scheme 107: Diels–Alder adducts from HMF or furfural with N-methylmaleimide.
Scheme 108: Pathway of the one-pot conversion of HMF into phthalic anhydride.
Scheme 109: Photocatalyzed preparation of humins (L-H) from HMF mixed with spoiled HMF residues (LMW-H) and fur...
Scheme 110: Asymmetric dipolar cycloadditions on HMF.
Scheme 111: Dipolar cycloadditions of HMF based nitrones to 3,4- and 3,5-substituted isoxazolidines.
Scheme 112: Production of δ-lactone-fused cyclopenten-2-ones from HMF.
Scheme 113: Aza-Piancatelli access to aza-spirocycles from HMF-derived intermediates.
Scheme 114: Cross-condensation of furfural, acetone and HMF into C13, C14 and C15 products.
Scheme 115: Base-catalyzed aldol condensation/dehydration sequences from HMF.
Scheme 116: Condensation of HMF and active methylene nitrile.
Scheme 117: MBH reactions involving HMF.
Scheme 118: Synthesis of HMF-derived ionic liquids.
Scheme 119: Reductive amination/enzymatic acylation sequence towards HMF-based surfactants.
Scheme 120: The formation of 5-chloromethylfurfural (CMF).
Scheme 121: Conversion of CMF to HMF, levulinic acid, and alkyl levulinates.
Scheme 122: Conversion of CMF to CMFCC and FDCC.
Scheme 123: Conversion of CMF to BHMF.
Scheme 124: Conversion of CMF to DMF.
Scheme 125: CMF chlorine atom substitutions toward HMF ethers and esters.
Scheme 126: Introduction of carbon nucleophiles in CMF.
Scheme 127: NHC-catalyzed remote enantioselective Mannich-type reactions of CMF.
Scheme 128: Conversion of CMF to promising biomass-derived dyes.
Scheme 129: Radical transformation of CMF with styrenes.
Scheme 130: Synthesis of natural herbicide δ-aminolevulinic acid from CMF.
Scheme 131: Four step synthesis of the drug ranitidine from CMF.
Scheme 132: Pd/CO2 cooperative catalysis for the production of HHD and HXD.
Scheme 133: Different ruthenium (Ru) catalysts for the ring-opening of 5-HMF to HHD.
Scheme 134: Proposed pathways for preparing HXD from HMF.
Scheme 135: MCP formation and uses.
Scheme 136: Cu(I)-catalyzed highly selective oxidation of HHD to 2,5-dioxohexanal.
Scheme 137: Synthesis of N‑substituted 3‑hydroxypyridinium salts from 2,5-dioxohexanal.
Scheme 138: Ru catalyzed hydrogenations of HHD to 1,2,5-hexanetriol (a) see ref. [396]; b) see ref. [397]).
Scheme 139: Aviation fuel range quadricyclanes produced by HXD.
Scheme 140: Synthesis of HDGK from HXD and glycerol as a chain extender.
Scheme 141: Synthesis of serinol pyrrole from HXD and serinol.
Scheme 142: Synthesis of pyrroles from HXD and nitroarenes.
Scheme 143: Two-step production of PX from cellulose via HXD.
Scheme 144: Preparation of HCPN from HMF via hydrogenation and ring rearrangement.
Scheme 145: Suggested pathways from HMF to HCPN.
Scheme 146: α-Alkylation of HCPN with ethylene gas.
Scheme 147: Synthesis of 3-(hydroxymethyl)cyclopentylamine from HMF via reductive amination of HCPN.
Scheme 148: Production of LGO and Cyrene® from biomass.
Scheme 149: Synthesis of HBO from LGO and other applications.
Scheme 150: Construction of m-Cyrene® homopolymer.
Scheme 151: Conversion of Cyrene® to THFDM and 1,6-hexanediol.
Scheme 152: RAFT co-polymerization of LGO and butadienes.
Scheme 153: Polycondensation of HO-LGOL and diols with dimethyl adipate.
Scheme 154: Self-condensation of Cyrene® and Claisen–Schmidt reactions.
Scheme 155: Synthesis of 5-amino-2-(hydroxymethyl)tetrahydropyran from Cyrene®.
Beilstein J. Org. Chem. 2025, 21, 1995–2006, doi:10.3762/bjoc.21.155
Graphical Abstract
Scheme 1: Illustration of chirality and the intrinsic remoteness of stereogenic elements for axial chirality ...
Scheme 2: Illustrations of assignment using point chirality.
Scheme 3: Examples of reactions that establish axial chirality derived from biaryls.
Scheme 4: Examples of reactions that establish axial chirality derived from C=C bonds.
Scheme 5: Examples of reactions that establish planar chirality.
Scheme 6: Examples of reactions that establish “inherent” chirality.
Scheme 7: Parameterization of asymmetric reactions that establish axial chirality.
Figure 1: The relationship between the numbers of non-hydrogen atoms (N) in the chiral catalysts and the valu...
Beilstein J. Org. Chem. 2025, 21, 1984–1994, doi:10.3762/bjoc.21.154
Graphical Abstract
Scheme 1: Alkyne arylation with diaryl-λ3-iodanes in the context of 1,2-silyl shift and potential cyclization....
Scheme 2: Competing mechanistic pathways for diene 10 and indene 11 formation.
Scheme 3: Reaction scope for the synthesis of arylated tetrahydrofurans 8. Conditions: All reactions were per...
Scheme 4: Synthesis of lactone and pyrrolidine derivatives. Conditions: ac7e = 0.1 mmol/mL. bReaction conditi...
Scheme 5: Proposed arylation–heterocyclization mechanism for internal nucleophile-containing silanes 7.
Scheme 6: Arylation of C5-chain containing acylamides 16a–c. aThe reaction was performed under modified condi...
Beilstein J. Org. Chem. 2025, 21, 1854–1863, doi:10.3762/bjoc.21.144
Graphical Abstract
Figure 1: Schematic representation of the modulation of MOF pore environments. A) de novo synthesis of severa...
Figure 2: A) Schematic representation of the reaction of KSU-1 with aliphatic isocyanates and the estimated c...
Scheme 1: Probable mechanisms for the Knoevenegel condensation reaction between benzaldehyde and malononitril...
Figure 3: A) Schematic representation of the reaction between benzaldehyde and malononitrile to form benzylid...
Figure 4: Graphical representation of the Knoevenagel catalysis results. A) Comparison of the reaction in tol...
Figure 5: Left: comparison of BMN and HPMM protons in 1H NMR spectra. Note that the peaks corresponding to HP...
Beilstein J. Org. Chem. 2025, 21, 1742–1747, doi:10.3762/bjoc.21.137
Graphical Abstract
Figure 1: Structures of fluorinated cyclopropanes evaluated in this study through quantum chemical methods.
Figure 2: (a) Electrostatic potential map of 1.2.3-c.c., highlighting the negative region (top side) and posi...
Figure 3: Calculated complexes of 1.2.3-c.c. with Na+ (top) and Cl− (bottom).
Beilstein J. Org. Chem. 2025, 21, 1422–1453, doi:10.3762/bjoc.21.106
Beilstein J. Org. Chem. 2025, 21, 1374–1387, doi:10.3762/bjoc.21.102
Graphical Abstract
Figure 1: Simplified schematic rendering of a high hydrostatic pressure reactor.
Scheme 1: High pressure-initiated synthesis of 1,3-dihydrobenzimidazoles 3a–d. The yields are GC yields and t...
Figure 2: Illustration of the cyclization reaction between chalcone (4) and 3-(trifluoromethyl)phenylhydrazin...
Scheme 2: High pressure-initiated catalyst- and solvent-free synthesis of pyrazoles 6a–c from chalcone (4) an...
Figure 3: Schematic representation of the cycling experiments: the major variables are the applied pressure, ...
Scheme 3: High pressure-initiated synthesis of the active pharmaceutical ingredients in Tylenol® and Aspirin®...
Scheme 4: High pressure-initiated esterification of alcohols 12a–g in a catalyst- and additional solvent-free...
Scheme 5: High pressure-initiated large scale syntheses of N-aryl- and N-alkylpyrroles at about 100 g scale.
Beilstein J. Org. Chem. 2025, 21, 1324–1373, doi:10.3762/bjoc.21.101
Graphical Abstract
Figure 1: Bond lengths and bond angles in oxetane at 140 K [2].
Figure 2: Analogy of 3-substituted oxetanes to carbonyl and gem-dimethyl groups [12].
Figure 3: Use of oxetanes in drug design – selected examples.
Figure 4: Examples of oxetane-containing natural products.
Scheme 1: Synthetic strategies towards construction of the oxetane ring.
Scheme 2: Overview of intramolecular Williamson etherification and competing Grob fragmentation.
Scheme 3: Synthesis of spiro-oxetanes via 1,4-C–H insertion and Williamson etherification.
Scheme 4: Use of phenyl vinyl selenone in the synthesis of spirooxindole oxetanes.
Scheme 5: Synthesis of bicyclic 3,5-anhydrofuranoses via double epoxide opening/etherification.
Scheme 6: Preparation of spirooxetanes by cycloisomerisation via MHAT/RPC.
Scheme 7: Oxetane synthesis via alcohol C–H functionalisation.
Scheme 8: Access to oxetanes 38 from α-acetyloxy iodides.
Scheme 9: The kilogram-scale synthesis of oxetane intermediate 41.
Scheme 10: Overview of the intramolecular opening of 3-membered rings.
Scheme 11: Synthesis of 4,7-dioxatricyclo[3.2.1.03,6]octane skeletons.
Scheme 12: Silicon-directed electrophilic cyclisation of homoallylic alcohols.
Scheme 13: Hydrosilylation–iodocyclisation of homopropargylic alcohols.
Scheme 14: Cu-catalysed intramolecular O-vinylation of γ-bromohomoallylic alcohols.
Scheme 15: Cu-catalysed intramolecular cross-coupling of hydroxyvinylstannanes.
Scheme 16: Isomerisation of oxiranyl ethers containing weakly carbanion-stabilising groups.
Scheme 17: Cyclisation of diethyl haloalkoxymalonates.
Scheme 18: Synthesis of oxetanes through a 1,5-HAT/radical recombination sequence.
Scheme 19: General approach to oxetanes via [2 + 2] cycloadditions.
Scheme 20: Synthesis of tricyclic 4:4:4 oxetanes through a photochemical triple cascade reaction.
Scheme 21: Iridium-catalysed Paternò–Büchi reaction between α-ketoesters and simple alkenes.
Scheme 22: Three-step synthesis of spirocyclic oxetanes 83 via Paternò–Büchi reaction, nucleophilic ring openi...
Scheme 23: Enantioselective Paternò–Büchi reaction catalysed by a chiral iridium photocatalyst.
Scheme 24: Synthesis of polysubstituted oxetanes 92 via Cu(II)-mediated formal [2 + 2] cycloadditions.
Scheme 25: Synthesis of alkylideneoxetanes via NHC- and DBU-mediated formal [2 + 2] cycloadditions.
Scheme 26: Use of sulphur-stabilised carbanions in ring expansions.
Scheme 27: Synthesis of α,α-difluoro(arylthio)methyl oxetanes.
Scheme 28: Ring expansion in an industrial synthesis of PF-06878031.
Scheme 29: Ring contraction of triflated 2-hydroxy-γ-lactones.
Scheme 30: Ring contraction in an industrial synthesis of PF-06878031.
Scheme 31: Photochemical ring contraction of 2,5-dihydrofurans by aryldiazoacetic acid esters.
Scheme 32: Synthesis of 3-oxetanones via O-H insertion of carbenes.
Scheme 33: Synthesis of phosphonate oxetanones via gold-mediated alkyne oxidation/O–H insertion.
Scheme 34: Syntheses and common derivatisations of 3-oxetanone.
Scheme 35: SN1 substitution of 3-aryloxetan-3-ols by thiols and alcohols.
Scheme 36: Fe–Ni dual-catalytic olefin hydroarylation towards 3-alkyl-3-(hetero)aryloxetanes.
Scheme 37: Synthesis of 3-aryloxetan-3-carboxylic acids.
Scheme 38: Decarboxylative alkylation of 3-aryloxetan-3-carboxylic acids.
Scheme 39: Synthesis of 3-amino-3-aryloxetanes via photoredox/nickel cross-coupling catalysis.
Scheme 40: Intermolecular cross-selective [2 + 2] photocycloaddition towards spirooxetanes.
Scheme 41: Synthesis of 3-aryl-3-aminooxetanes via defluorosulphonylative coupling.
Scheme 42: Two-step synthesis of amide bioisosteres via benzotriazolyl Mannich adducts 170.
Scheme 43: Functionalisation of oxetanyl trichloroacetimidates 172.
Scheme 44: Synthesis of oxetane-amino esters 176.
Scheme 45: Tandem Friedel–Crafts alkylation/intramolecular ring opening of 3-aryloxetan-3-ols.
Scheme 46: Synthesis of polysubstituted furans and pyrroles.
Scheme 47: Synthesis of oxazolines and bisoxazolines.
Scheme 48: Tandem, one-pot syntheses of various polycyclic heterocycles.
Scheme 49: Synthesis of 1,2-dihydroquinolines via skeletal reorganisation of oxetanes.
Scheme 50: Synthesis of benzoindolines and 2,3-dihydrobenzofurans and their derivatisations.
Scheme 51: Synthesis of polysubstituted 1,4-dioxanes.
Scheme 52: Preparation of various lactones via ring opening of oxetane-carboxylic acids 219.
Scheme 53: Tsuji-Trost allylation/ring opening of 3-aminooxetanes.
Scheme 54: Arylative skeletal rearrangement of 3-vinyloxetan-3-ols to 2,5-dihydrofurans.
Scheme 55: Reductive opening of oxetanes using catalytic Mg–H species.
Scheme 56: Opening of oxetanes by silyl ketene acetals.
Scheme 57: Rhodium-catalysed hydroacylation of oxetanes.
Scheme 58: Generation of radicals from oxetanes mediated by a vitamin B12-derived cobalt catalyst.
Scheme 59: Reductive opening of oxetanes by B–Si frustrated Lewis pairs.
Scheme 60: Zirconocene-mediated reductive opening of oxetanes.
Scheme 61: Enantioselective syntheses of small and medium-size rings using chiral phosphoric acids.
Scheme 62: Asymmetric synthesis of 2,3-dihydrobenzo[b]oxepines catalysed by a chiral scandium complex.
Scheme 63: Enantioselective synthesis of 1,3-bromohydrins under a chiral squaramide catalysis.
Scheme 64: Enantioselective opening of 2-aryl-2-ethynyloxetanes by anilines.
Scheme 65: Ru-catalysed insertion of diazocarbonyls into oxetanes.
Scheme 66: Ring expansion of oxetanes by stabilised carbenes generated under blue light irradiation.
Scheme 67: Expansion of oxetanes via nickel-catalysed insertion of alkynyltrifluoroborates.
Scheme 68: Nickel-catalysed expansion of oxetanes into ε-caprolactones.
Scheme 69: Expansion of oxetanes via cobalt-catalysed carbonyl insertion.
Scheme 70: Gold-catalysed intramolecular 1,1-carboalkoxylation of oxetane-ynamides.
Scheme 71: Expansion of oxetanes by stabilised sulphoxonium ylides.
Scheme 72: Cu-catalysed ring expansion of 2-vinyloxetanes by diazoesters.
Scheme 73: Total synthesis of (+)-oxetin.
Scheme 74: Total synthesis of racemic oxetanocin A.
Scheme 75: Total synthesis of (−)-merrilactone A.
Scheme 76: Total synthesis of (+)-dictyoxetane.
Scheme 77: Total synthesis of ent-dichrocephone B.
Scheme 78: Total synthesis of (−)-mitrephorone A.
Scheme 79: Total synthesis of (−)-taxol.
Beilstein J. Org. Chem. 2025, 21, 1183–1191, doi:10.3762/bjoc.21.95
Graphical Abstract
Figure 1: Chemical structures of fully π-fused propellanes and their typical reaction patterns toward electro...
Figure 2: a) Synthesis of methylene-alternating copolymers of fully π-fused propellanes. DCE, 1,2-dichloroeth...
Figure 3: Gas adsorption (filled circles) and desorption (open circles) isotherms of [3.3.3]_oligo (dark red)...
Beilstein J. Org. Chem. 2025, 21, 955–963, doi:10.3762/bjoc.21.79
Graphical Abstract
Figure 1: The structure of brevicolline ((S)-1) and brevicarine (2).
Scheme 1: Synthesis of racemic brevicolline ((±)-1) starting from 1-methyl-9H-β-carbolin-4-yl trifluoromethan...
Scheme 2: Synthesis of brevicarine (2) from brevicolline ((S)-1).
Scheme 3: First total synthesis of brevicarine (2).
Scheme 4: Multistep synthesis of brevicarine (2) starting from nitrovinylindole 19.
Scheme 5: New synthesis variants for the preparation of brevicarine alkaloid (2) and its synthetic derivative ...
Scheme 6: Preparation of carbamate 28 and subsequent reduction with LiAlH4.
Scheme 7: Experiments for the synthesis of racemic brevicolline ((±)-1), and formation of unexpected products....
Figure 2: X-ray structure of compound 31.
Beilstein J. Org. Chem. 2025, 21, 890–914, doi:10.3762/bjoc.21.73
Graphical Abstract
Scheme 1: Ligand-controlled regiodivergent C1 insertion into arynes [19].
Scheme 2: Ligand effect in homogenous gold catalysis enabling regiodivergent π-bond-activated cyclization [20].
Scheme 3: Ligand-controlled palladium(II)-catalyzed regiodivergent carbonylation of alkynes [21].
Scheme 4: Catalyst-controlled annulations of strained cyclic allenes with π-allyl palladium complexes and pro...
Scheme 5: Ring expansion of benzosilacyclobutenes with alkynes [23].
Scheme 6: Photoinduced regiodivergent and enantioselective cross-coupling [24].
Scheme 7: Catalyst-controlled regiodivergent and enantioselective formal hydroamination of N,N-disubstituted ...
Scheme 8: Catalyst-tuned regio- and enantioselective C(sp3)–C(sp3) coupling [31].
Scheme 9: Catalyst-controlled annulations of bicyclo[1.1.0]butanes with vinyl azides [32].
Scheme 10: Solvent-driven reversible macrocycle-to-macrocycle interconversion [39].
Scheme 11: Unexpected solvent-dependent reactivity of cyclic diazo imides and mechanism [40].
Scheme 12: Palladium-catalyzed annulation of prochiral N-arylphosphonamides with aromatic iodides [41].
Scheme 13: Time-dependent enantiodivergent synthesis [42].
Scheme 14: Time-controlled palladium-catalyzed divergent synthesis of silacycles via C–H activation [43].
Scheme 15: Proposed mechanism for the time-controlled palladium-catalyzed divergent synthesis of silacycles [43].
Scheme 16: Metal-free temperature-controlled regiodivergent borylative cyclizations of enynes [45].
Scheme 17: Nickel-catalyzed switchable site-selective alkene hydroalkylation by temperature regulation [46].
Scheme 18: Copper-catalyzed decarboxylative amination/hydroamination sequence [48].
Scheme 19: Proposed mechanism of copper-catalyzed decarboxylative amination/hydroamination sequence [48].
Scheme 20: Enantioselective chemodivergent three-component radical tandem reactions [49].
Scheme 21: Substrate-controlled synthesis of indoles and 3H-indoles [52].
Scheme 22: Controlled mono- and double methylene insertions into nitrogen–boron bonds [53].
Scheme 23: Copper-catalyzed substrate-controlled carbonylative synthesis of α-keto amides and amides [54].
Scheme 24: Divergent sulfur(VI) fluoride exchange linkage of sulfonimidoyl fluorides and alkynes [55].
Scheme 25: Modular and divergent syntheses of protoberberine and protonitidine alkaloids [56].
Beilstein J. Org. Chem. 2025, 21, 755–765, doi:10.3762/bjoc.21.59
Graphical Abstract
Figure 1: Crystal structure of the calcium diphenyl phosphate complex 4. Hydrogen atoms are omitted for clari...
Scheme 1: Synthesis of the calcium diphenyl phosphate model complex 4 from phosphoric acid 3 and Ca(OiPr)2.
Figure 2: (A) Proposed catalytic cycle for the hydrocyanation of hydrazones with the Ca–BINOL phosphate catal...
Figure 3: Reaction energy profile for the hydrocyanation of Z-hydrazone 1, (depicted is the pathway that give...
Figure 4: Transition-state structure TS 8 for internal rotation, mixing conformational (Z/E)-pathways with op...
Figure 5: Replacement step after internal rotation in 11 via TS8 and reaction with TMSCN to give adduct 13 (s...
Beilstein J. Org. Chem. 2025, 21, 749–754, doi:10.3762/bjoc.21.58
Graphical Abstract
Scheme 1: Synthetic strategies for the construction of spirotetrahydroquinoline (STHQ) scaffolds.
Scheme 2: Substrate scope. General reaction conditions: aniline 1 (0.2 mmol), 2 (0.4 mmol), and Cu(TFA)2 (0.0...
Scheme 3: Scale-up reaction.a
Scheme 4: Proposed mechanism.
Beilstein J. Org. Chem. 2025, 21, 369–406, doi:10.3762/bjoc.21.27
Graphical Abstract
Scheme 1: Continuum in the mechanistic pathway of glycosylation [32] reactions ranging between SN2 and SN1.
Scheme 2: Formation of 1,2-trans glycosides by neighbouring group participation with acyl protection in C-2 p...
Scheme 3: Solvent-free activation [92] of disarmed per-acetylated (15) and per-benzoylated (18) glycosyl donors.
Scheme 4: Synthesis of donor 2-(2,2,2-trichloroethoxy)glucopyrano-[2,1-d]-2-oxazoline 22 [94] and regioselective ...
Scheme 5: The use of levulinoyl protection for an orthogonal glycosylation reaction.
Figure 1: The derivatives 32–36 of the pivaloyl group.
Scheme 6: Benzyl and cyanopivalolyl ester-protected hexarhamnoside derivative 37 and its global deprotection ...
Scheme 7: Orthogonal chloroacetyl group deprotection in oligosaccharide synthesis [113].
Figure 2: The derivatives of the chloroacetyl group: CAMB protection (41) [123], CAEB protection (42) [124], POMB prote...
Scheme 8: Use of the (2-nitrophenyl)acetyl protecting group [126] as the neighbouring group protecting group at th...
Scheme 9: Neighbouring group participation protocol by the BnPAc protecting group [128] in the C-2 position.
Scheme 10: Glycosylation reaction with O-PhCar (54) and O-Poc (55) donors showing high β-selectivity [133].
Scheme 11: Neighbouring group participation rendered by an N-benzylcarbamoyl (BnCar) group [137] at the C-2 positio...
Scheme 12: Stereoselectivity obtained from glycosylation [138] with 2-O-(o-trifluoromethylbenzenesulfonyl)-protecte...
Scheme 13: (a) Plausible mechanistic pathway for glycosylation with C-2 DMTM protection [139] and (b) example of a ...
Scheme 14: Glycosylation reactions employing MOM 78, BOM 81, and NAPOM 83-protected thioglycoside donors. Reag...
Scheme 15: Plausible mechanistic pathway for alkoxymethyl-protected glycosyl donors. Path A. Expected product ...
Scheme 16: Plausible mechanistic pathway for alkoxymethyl-protected glycosyl donors [147].
Scheme 17: A. Formation of α-glycosides and B formation of β-glycosides by using chiral auxiliary neighbouring...
Scheme 18: Bimodal participation of 2-O-(o-tosylamido)benzyl (TAB) protecting group to form both α and β-isome...
Scheme 19: (a) 1,2-trans-Directing nature using C-2 cyanomethyl protection and (b) the effect of acceptors and...
Scheme 20: 1,3-Remote assistance by C-3-ester protection for gluco- and galactopyranosides to form 1,2-cis gly...
Scheme 21: 1,6-Remote assistance by C-6-ester protection for gluco- and galactopyranosides to form 1,2-cis gly...
Scheme 22: 1,4-Remote assistance by C-4-ester protection for galactopyranosides to form 1,2-cis glycosidic pro...
Scheme 23: Different products obtained on activation of axial 3-O and equatorial 3-O ester protected glycoside...
Scheme 24: The role of 3-O-protection on the stereochemistry of the produced glycoside [191].
Scheme 25: The role of 4-O-protection on the stereochemistry of the produced glycosides.
Scheme 26: Formation and subsequent stability of the bicyclic oxocarbenium intermediate formed due to remote p...
Scheme 27: The role a C-6 p-nitrobenzoyl group on the stereochemistry of the glycosylated product [196].
Scheme 28: Difference in stereoselectivity obtained in glycosylation reactions by replacing non-participating ...
Scheme 29: The role of electron-withdrawing and electron-donating substituents on the C-4 acetyl group in glyc...
Scheme 30: Effect of the introduction of a methyl group in the C-4 position on the glycosylation with more rea...
Figure 3: Remote group participation effect exhibited by the 2,2-dimethyl-2-(o-nitrophenyl)acetyl (DMNPA) pro...
Scheme 31: The different stereoselectivities obtained by Pic and Pico donors on being activated by DMTST.
Figure 4: Hydrogen bond-mediated aglycon delivery (HAD) in glycosylation reactions for 1,2-cis 198a and 1,2-t...
Scheme 32: The role of different acceptor with 6-O-Pic-protected glycosyl donors.
Scheme 33: The role of the remote C-3 protection on various 4,6-O-benzylidene-protected mannosyl donors affect...
Scheme 34: The dual contribution of the DTBS group in glycosylation reactions [246,247].
Beilstein J. Org. Chem. 2025, 21, 348–357, doi:10.3762/bjoc.21.25
Graphical Abstract
Figure 1: An overview of previously synthesized 1,2-benzothiazines [36-39].
Scheme 1: General scheme for the synthesis of pyrazolo-1,2-benzothiazine-N-aryl/benzyl/cyclohexylacetamide.
Figure 2: An example of contrasting 1H NMR signals for monoalkylated (7a) and dialkylated (7l) derivatives, (...