Search for "dehalogenation" in Full Text gives 59 result(s) in Beilstein Journal of Organic Chemistry.
Beilstein J. Org. Chem. 2013, 9, 1977–2001, doi:10.3762/bjoc.9.234
Graphical Abstract
Scheme 1: Amine radical cations’ mode of reactivity.
Scheme 2: Reductive quenching of photoexcited Ru complexes by Et3N.
Scheme 3: Photoredox aza-Henry reaction.
Scheme 4: Formation of iminium ions using BrCCl3 as stoichiometric oxidant.
Scheme 5: Oxidative functionalization of N-aryltetrahydroisoquinolines using Eosin Y.
Scheme 6: Synthetic and mechanistic studies of Eosin Y-catalyzed aza-Henry reaction.
Scheme 7: Oxidative functionalization of N-aryltetrahydroisoquinolines using RB and GO.
Scheme 8: Merging Ru-based photoredox catalysis and Lewis base catalysis for the Mannich reaction.
Scheme 9: Merging Au-based photoredox catalysis and Lewis base catalysis for the Mannich reaction.
Scheme 10: Merging Ru-based photoredox catalysis and Cu-catalyzed alkynylation reaction.
Scheme 11: Merging Ru-based photoredox catalysis and NHC catalysis.
Scheme 12: 1,3-Dipolar cycloaddition of photogenically formed azomethine ylides.
Scheme 13: Plausible mechanism for photoredox 1,3-dipolar cycloaddition.
Scheme 14: Photoredox-catalyzed cascade reaction for the synthesis of fused isoxazolidines.
Scheme 15: Plausible mechanism for the photoredox-catalyzed cascade reaction.
Scheme 16: Photoredox-catalyzed α-arylation of glycine derivatives.
Scheme 17: Photoredox-catalyzed α-arylation of amides.
Scheme 18: Intramolecular interception of iminium ions by sulfonamides.
Scheme 19: Intramolecular interception of iminium ions by alcohols and sulfonamides.
Scheme 20: Intermolecular interception of iminium ions by phosphites.
Scheme 21: Photoredox-catalyzed oxidative phosphonylation by Eosin Y.
Scheme 22: Conjugated addition of α-amino radicals to Michael acceptors.
Scheme 23: Conjugated addition of α-amino radicals to Michael acceptors assisted by a Brønsted acid.
Scheme 24: Conjugated addition of α-amino radicals derived from anilines to Michael acceptors.
Scheme 25: Oxygen switch between two pathways involving α-amino radicals.
Scheme 26: Interception of α-amino radicals by azodicarboxylates.
Scheme 27: α-Arylation of amines.
Scheme 28: Plausible mechanism for α-arylation of amines.
Scheme 29: Photoinduced C–C bond cleavage of tertiary amines.
Scheme 30: Photoredox cleavage of C–C bonds of 1,2-diamines.
Scheme 31: Proposed mechanism photoredox cleavage of C–C bonds.
Scheme 32: Intermolecular [3 + 2] annulation of cyclopropylamines with olefins.
Scheme 33: Proposed mechanism for intermolecular [3 + 2] annulation.
Scheme 34: Photoinduced clevage of N–N bonds of aromatic hydrazines and hydrazides.
Beilstein J. Org. Chem. 2012, 8, 1936–1998, doi:10.3762/bjoc.8.225
Graphical Abstract
Figure 1: Loschmidt’s structure proposal for benzene (1) (Scheme 181 from [3]) and the corresponding modern stru...
Figure 2: The first isolated bisallenes.
Figure 3: Carbon skeletons of selected bisallenes discussed in this review.
Scheme 1: The preparation of 1,2,4,5-hexatetraene (2).
Scheme 2: The preparation of a conjugated bisallene by the DMS-protocol.
Scheme 3: Preparation of the 3-deuterio- and 3,4-dideuterio derivatives of 24.
Scheme 4: A versatile method to prepare alkylated conjugated bisallenes and other allenes.
Scheme 5: A preparation of 3,4-dimethyl-1,2,4,5-hexatetraene (38).
Scheme 6: A (C6 + 0)-approach to 1,2,4,5-hexatetraene (2).
Scheme 7: The preparation of a fully alkylated bisallenes from a 2,4-hexadiyne-1,6-diol diacetate.
Scheme 8: The preparation of the first phenyl-substituted conjugated bisallenes 3 and 4.
Scheme 9: Selective hydrogenation of [5]cumulenes to conjugated bisallenes: another (C6 + 0)-route.
Scheme 10: Aryl-substituted conjugated bisallenes by a (C3 + C3)-approach.
Scheme 11: Hexaphenyl-1,2,4,5-hexatetraene (59) by a (C3 + C3)-approach.
Scheme 12: An allenation route to conjugated bisallenes.
Scheme 13: The preparation of 3,4-difunctionalized conjugated bisallenes.
Scheme 14: Problems during the preparation of sulfur-substituted conjugated bisallenes.
Scheme 15: The preparation of 3,4-dibromo bisallenes.
Scheme 16: Generation of allenolates by an oxy-Cope rearrangement.
Scheme 17: A linear trimerization of alkynes to conjugated bisallenes: a (C2 + C2 + C2)-protocol.
Scheme 18: Preparation of a TMS-substituted conjugated bisallene by a C3-dimerization route.
Scheme 19: A bis(trimethylsilyl)bisallene by a C3-coupling protocol.
Scheme 20: The rearrangement of highly substituted benzene derivatives into their conjugated bisallenic isomer...
Scheme 21: From fully substituted benzene derivatives to fully substituted bisallenes.
Scheme 22: From a bicyclopropenyl to a conjugated bisallene derivative.
Scheme 23: The conversion of a bismethylenecyclobutene into a conjugated bisallene.
Scheme 24: The preparation of monofunctionalized bisallenes.
Scheme 25: Preparation of bisallene diols and their cyclization to dihydrofurans.
Scheme 26: A 3,4-difunctionalized conjugated bisallene by a C3-coupling process.
Scheme 27: Preparation of a bisallenic diketone by a coupling reaction.
Scheme 28: Sulfur and selenium-substituted bisallenes by a [2.3]sigmatropic rearrangement.
Scheme 29: The biallenylation of azetidinones.
Scheme 30: The preparation of a fully ferrocenylated conjugated bisallene.
Scheme 31: The first isomerization of a 1,5-hexadiyne to a 1,2,4,5-hexatetraene.
Scheme 32: The preparation of alkynyl-substituted bisallenes by a C3-dimerization protocol.
Scheme 33: Preparation of another completely ferrocenylated bisallene.
Scheme 34: The cyclization of 1,5-hexadiyne (129) to 3,4-bismethylenecyclobutene (130) via 1,2,4,5-hexatetraen...
Scheme 35: Stereochemistry of the thermal cyclization of bisallenes to bismethylenecyclobutenes.
Scheme 36: Bisallene→bismethylenecyclobutene ring closures in the solid state.
Scheme 37: A bisallene cyclization/dimerization reaction.
Scheme 38: A selection of Diels–Alder additions of 1,2,4,5-hexatetraene with various double-bond dienophiles.
Scheme 39: The stereochemistry of the [2 + 4] cycloaddition to conjugated bisallenes.
Scheme 40: Preparation of azetidinone derivatives from conjugated bisallenes.
Scheme 41: Cycloaddition of heterodienophiles to a conjugated bisallene.
Scheme 42: Addition of triple-bond dienophiles to conjugated bisallenes.
Scheme 43: Sulfur dioxide addition to conjugated bisallenes.
Scheme 44: The addition of a germylene to a conjugated bisallene.
Scheme 45: Trapping of conjugated bisallenes with phosphinidenes.
Scheme 46: The cyclopropanantion of 1,2,4,5-hexatetraene (2).
Scheme 47: Photochemical reactions involving conjugated bisallenes.
Scheme 48: Base-catalyzed isomerizations of conjugated bisallenes.
Scheme 49: Ionic additions to a conjugated bisallene.
Scheme 50: Oxidation reactions of a conjugated bisallene.
Scheme 51: The mechanism of oxidation of the bisallene 24.
Scheme 52: CuCl-catalyzed cyclization of 1,2,4,5-hexatetraene (2).
Scheme 53: The conversion of conjugated bisallenes into cyclopentenones.
Scheme 54: Oligomerization of a conjugated bisallene by nickel catalysts.
Scheme 55: Generation of 1,2,5,6-heptatetraene (229) as a reaction intermediate.
Scheme 56: The preparation of a stable derivative of 1,2,5,6-heptatetraene.
Scheme 57: A bisallene with a carbonyl group as a spacer element.
Scheme 58: The first preparation of 1,2,6,7-octatetraene (242).
Scheme 59: Preparation of 1,2,6,7-octatetraenes by (C4 + C4)-coupling of enynes.
Scheme 60: Preparation of 1,2,6,7-octatetraenes by (C4 + C4)-coupling of homoallenyl bromides.
Scheme 61: Preparation of 1,2,6,7-octatetraenes by alkylation of propargylic substrates.
Scheme 62: Preparation of two highly functionalized 1,2,6,7-octatetraenes.
Scheme 63: Preparation of several higher α,ω-bisallenes.
Scheme 64: Preparation of different alkyl derivatives of α,ω-bisallenes.
Scheme 65: The preparation of functionalized 1,2,7,8-nonatetraene derivatives.
Scheme 66: Preparation of functionalized α,ω-bisallenes.
Scheme 67: The preparation of an α,ω-bisallene by direct homologation of an α,ω-bisalkyne.
Scheme 68: The gas-phase pyrolysis of 4,4-dimethyl-1,2,5,6-heptatetraene (237).
Scheme 69: Gas-phase pyrolysis of 1,2,6,7-octatetraene (242).
Scheme 70: The cyclopropanation of 1,2,6,7-octatetraene (242).
Scheme 71: Intramolecular cyclization of 1,2,6,7-octatetraene derivatives.
Scheme 72: The gas-phase pyrolysis of 1,2,7,8-nonatetraene (265) and 1,2,8,9-decatetraene (266).
Scheme 73: Rh-catalyzed cyclization of a functionalized 1,2,7,8-nonatetraene.
Scheme 74: A triple cyclization involving two different allenic substrates.
Scheme 75: Bicyclization of keto derivatives of 1,2,7,8-nonatetraene.
Scheme 76: The preparation of complex organic compounds from functionalized bisallenes.
Scheme 77: Cycloisomerization of an α,ω-bisallene containing a C9 tether.
Scheme 78: Organoborane polymers from α,ω-bisallenes.
Scheme 79: Preparation of trans- (337) and cis-1,2,4,6,7-octapentaene (341).
Scheme 80: The preparation of 4-methylene-1,2,5,6-heptatetraene (349).
Scheme 81: The preparation of acetylenic bisallenes.
Scheme 82: The preparation of derivatives of hydrocarbon 351.
Scheme 83: The construction of macrocyclic alleno-acetylenes.
Scheme 84: Preparation and reactions of 4,5-bismethylene-1,2,6,7-octatetraene (365).
Scheme 85: Preparation of 1,2-bis(propadienyl)benzene (370).
Scheme 86: The preparation of 1,4-bis(propadienyl)benzene (376).
Scheme 87: The preparation of aromatic and heteroaromatic bisallenes by metal-mediated coupling reactions.
Scheme 88: Double cyclization of an aromatic bisallene.
Scheme 89: Preparation of an allenic [15]paracyclophane by a ring-closing metathesis reaction of an aromatic α...
Scheme 90: Preparation of a macrocyclic ring system containing 1,4-bis(propadienyl)benzene units.
Scheme 91: Preparation of copolymers from 1,4-bis(propadienyl)benzene (376).
Scheme 92: A boration/copolymerization sequence of an aromatic bisallene and an aromatic bisacetylene.
Scheme 93: Formation of a layered aromatic bisallene.
Figure 4: The first members of the semicyclic bisallene series.
Scheme 94: Preparation of the first bis(vinylidene)cyclobutane derivative.
Scheme 95: Dimerization of strain-activated cumulenes to bis(vinylidene)cyclobutanes.
Scheme 96: Photodimerization of two fully substituted butatrienes in the solid state.
Scheme 97: Preparation of the two parent bis(vinylidene)cyclobutanes.
Scheme 98: The preparation of 1,3-bis(vinylidene)cyclopentane and its thermal isomerization.
Scheme 99: The preparation of the isomeric bis(vinylidene)cyclohexanes.
Scheme 100: Bi- and tricyclic conjugated bisallenes.
Scheme 101: A selection of polycyclic bisallenes.
Scheme 102: The first endocyclic bisallenes.
Figure 5: The stereochemistry of 1,2,6,7-cyclodecatetraene.
Scheme 103: The preparation of several endocyclic bisallenes.
Scheme 104: Synthesis of diastereomeric derivatives of 1,2,6,7-cyclodecatetraene.
Scheme 105: Preparation of a derivative of 1,2,8,9-cyclotetradecatetraene.
Scheme 106: The preparation of keto derivatives of cyclic bisallenes.
Scheme 107: The preparation of cyclic biscumulenic ring systems.
Scheme 108: Cyclic bisallenes in natural- and non-natural-product chemistry.
Scheme 109: The preparation of iron carbonyl complexes from cyclic bisallenes.
Figure 6: A selection of unknown exocyclic bisallenes that should have interesting chemical properties.
Scheme 110: The thermal isomerization of 1,2-diethynylcyclopropanes and -cyclobutanes.
Scheme 111: Intermediate generation of a cyclooctapentaene.
Scheme 112: Attempted preparation of a cyclodecahexaene.
Scheme 113: The thermal isomerization of 1,5,9-cyclododecatriyne (511) into [6]radialene (514).
Scheme 114: An isomerization involving a diketone derived from a conjugated bisallene.
Scheme 115: Typical reaction modes of heteroorganic bisallenes.
Scheme 116: Generation and thermal behavior of acyclic hetero-organic bisallenes.
Scheme 117: Generation of bis(propadienyl)thioether.
Scheme 118: The preparation of a bisallenic sulfone and its thermal isomerization.
Scheme 119: Bromination of the bisallenic sulfone 535.
Scheme 120: Metalation/hydrolysis of the bisallenic sulfone 535.
Scheme 121: Aromatic compounds from hetero bisallenes.
Scheme 122: Isomerization/cyclization of bispropargylic ethers.
Scheme 123: The preparation of novel aromatic systems by base-catalyzed isomerization of bispropargyl ethers.
Scheme 124: The isomerization of bisacetylenic thioethers to bicyclic thiophenes.
Scheme 125: Aromatization of macrocyclic bispropargylic sulfides.
Scheme 126: Preparation of ansa-compounds from macrocyclic bispropargyl thioethers.
Scheme 127: Alternate route for cyclization of a heterorganic bisallene.
Scheme 128: Multiple isomerization/cyclization of “double” bispropargylic thioethers.
Scheme 129: Preparation of a bisallenyl disulfide and its subsequent bicyclization.
Scheme 130: Thermal cyclization of a bisallenyl thiosulfonate.
Scheme 131: Some reactions of heteroorganic bisallenes with two sulfur atoms.
Scheme 132: Further methods for the preparation of heteroorganic bisallenes.
Scheme 133: Cyclization reactions of heteroorganic bisallenes.
Scheme 134: Thermal cycloadditions of bisallenic tertiary amines.
Scheme 135: Cyclization of a bisallenic tertiary amine in the presence of a transition-metal catalyst.
Scheme 136: A Pauson–Khand reaction of a bisallenic ether.
Scheme 137: Formation of a 2:1adduct from two allenic substrates.
Scheme 138: A ring-forming silastannylation of a bisallenic tertiary amine.
Scheme 139: A three-component cyclization involving a heterorganic bisallene.
Scheme 140: Atom-economic construction of a complex organic framework from a heterorganic α,ω-bisallene.
Beilstein J. Org. Chem. 2012, 8, 1705–1709, doi:10.3762/bjoc.8.194
Graphical Abstract
Figure 1: Structures of well-known serotonin 5-HT2A agonists 1a,b, 2, and 3, and compounds 4 and 5 reported i...
Scheme 1: Synthesis of arylcyclopropane carboxylic acids from the corresponding cinnamic acids, followed by h...
Scheme 2: Conversion of arylcyclopropane carboxylic acids 10a,b to the amines 4 and 5, and chemical resolutio...
Scheme 3: Chemical resolution of arylcyclopropane carboxylic acid 9 followed by bromination.
Beilstein J. Org. Chem. 2012, 8, 522–527, doi:10.3762/bjoc.8.59
Graphical Abstract
Figure 1: Synthetic route to transform oxyglycal I to a septanoside V.
Scheme 1: Reaction conditions: (i) NaOMe, PhMe, reflux, 8 h; (ii) methyl acrylate (for 3); tert-butyl acrylat...
Scheme 2: Reaction conditions: (i) phenylboronic acid (for 8); 4-methoxyphenylboronic acid (for 9); 3-methylp...
Scheme 3: Reaction conditions: (i) phenylacetylene (for 11); oct-1-yne (for 12); Pd(PPh3)2Cl2 (20 mol %), CuI...
Scheme 4: Reaction conditions: (i) Pd/C (10 %), H2, MeOH, rt, 24 h; (ii) NaBH4, MeOH, 0 °C to rt, 3 h.
Beilstein J. Org. Chem. 2011, 7, 735–739, doi:10.3762/bjoc.7.83
Graphical Abstract
Figure 1: Schematic diagram of the continuous flow reactor (left) and the column top (right).
Scheme 1: Hydrogenation of ethyl cinnamate.
Scheme 2: Hydrogenation of trans-stilbene and trans-chalcone.
Scheme 3: Hydrogenation of nitrobenzene and deprotection of the Cbz group.
Scheme 4: Hydrogenation in water.
Beilstein J. Org. Chem. 2011, 7, 243–245, doi:10.3762/bjoc.7.32
Graphical Abstract
Figure 1: The four building blocks (units) A–D of cryptophycin-1 (1) and cryptophycin-52 (2).
Scheme 1: Synthesis of the unit B precursor from D-tyrosine (3). Reagents and conditions [7]: a) SO2Cl2, AcOH, r...
Scheme 2: Unit B synthesis by a chiral PTC approach. Reagents and conditions [9]: a) N-(Diphenylmethylene)glycin...
Scheme 3: Unit B precursor 4 synthesis by asymmetric hydrogenation. Reagents and conditions: a) 3-Chloro-4-me...
Beilstein J. Org. Chem. 2011, 7, 222–233, doi:10.3762/bjoc.7.30
Graphical Abstract
Figure 1: Molecular analogues of the Platonic solids.
Figure 2: The structure of [Mo6Cl8]4+ demonstrates the reciprocal relationship between the cube and the octah...
Figure 3: The deltahedra corresponding to the structures of the closo-boranes [BxHx]2−.
Scheme 1: The first synthesis of a tetrahedrane 19 by Maier.
Scheme 2: The conversion of Dewar benzenes to [3]-prismanes.
Scheme 3: Synthesis of [3]prismane 9 by Katz.
Scheme 4: Synthesis of cubane 10 by Eaton.
Scheme 5: Synthesis of cubane 10 by Pettit.
Scheme 6: Failed routes to [5]-prismane 11.
Scheme 7: Synthesis of [5]prismane 11 by Eaton.
Scheme 8: Retrosynthetic analysis for several approaches to dodecahedrane 16.
Scheme 9: Paquette´s synthesis of dodecahedrane 16.
Scheme 10: Prinzbach´s synthesis of dodecahedrane 16.
Figure 4: The as yet unknown polyhedranes 12–15.
Figure 5: Coupling of two Dewar benzenes.
Scheme 11: A possible route to octahedrane 12.
Scheme 12: A possible route to nonahedrane 13.
Figure 6: Capping [4]peristylane with a four-membered ring system.
Scheme 13: A possible route to decahedrane 14.
Figure 7: A possible route to undecahedrane 15 (left: side view; right: top view).
Scheme 14: Synthetic routes to trigonal prismatic hexasilanes 71a and hexagermanes 71b.
Scheme 15: Synthetic routes to octasila- and octagerma-cubanes.
Scheme 16: Synthesis of an octastannacubane and a decastannapentaprismane.
Scheme 17: Synthesis of a heterocubane.
Figure 8: D3d symmetric C8H8, a bis-truncated cubane.
Beilstein J. Org. Chem. 2011, 7, 29–33, doi:10.3762/bjoc.7.5
Graphical Abstract
Figure 1: Sertindole (1), process related impurities and metabolites.
Scheme 1: Reagents and conditions: i) K2CO3, CuBr, ethylenediamine, DMF 130–135 °C; ii) CH3COOH, CF3COOH, 100...
Scheme 2: Reagents, conditions (and yields): i) (a) pH adjusted to 6; (b) Pd/C, HCOONH4, AcOH, MeOH, reflux (...
Scheme 3: Reagents, conditions (and yields): i) 16, K2CO3, KI, MIBK, reflux (73.9%).
Scheme 4: Reagents, conditions (and yields): i) Cs2CO3, DMF, 130–135 °C; ii) 14, CH3COOH, CF3COOH, 100–105 °C...
Scheme 5: Reagents, conditions (and yields): i) (a) pH adjusted to 6–7; (b) H2, PtO2, MeOH, AcOH, 30–35 °C (7...
Scheme 6: Reagents, conditions (and yields): i) 12, K2CO3, Cu(II)Br, ethylenediamine, DMF, 130–135 °C, (51%);...
Scheme 7: Reagents, conditions (and yield): i) (a) 16, Et3N, NaI, CH3CN, reflux; (b) column chromatography (1...
Scheme 8: Reagents, conditions (and yield): i) (a) mCPBA, MeOH, 40–45 °C; (b) column chromatography (52.2%).
Beilstein J. Org. Chem. 2007, 3, No. 46, doi:10.1186/1860-5397-3-46
Graphical Abstract
Figure 1: Xanthates 1a, 2a and their corresponding alkanes.
Figure 2: Deuterated O-ethyl-S-ethyl dithiocarbonates 3–5, deuterated adduct 1d and alkane 1e.
Figure 3: Kinetics of the reduction of compound 1a in C6H6 at 20°C.
Scheme 1: Preparation of Et3B-d15.