Search for "methyl propiolate" in Full Text gives 25 result(s) in Beilstein Journal of Organic Chemistry.
Beilstein J. Org. Chem. 2024, 20, 2171–2207, doi:10.3762/bjoc.20.187
Graphical Abstract
Figure 1: Examples of compounds covered in this review categorized in six sub-classes (see text).
Figure 2: Examples of compounds not covered in this review.
Figure 3: Wrongly assigned and thus obsolete structures (details will be discussed in the respective chapters...
Figure 4: Alternariol with the correct IUPAC numbering and an occasionally used numbering based on the biphen...
Figure 5: Alternariol O-methyl ethers.
Figure 6: Alternariol O-glycosides.
Figure 7: Alternariol O-acetates and O-sulfates.
Figure 8: 2-Hydroxy- and 4-hydroxy-substituted alternariol and its O-methyl ethers.
Figure 9: Chloro- and amino-substituted alternariol and its O-methyl ethers.
Figure 10: Presumed alternariol derivatives with non-canonical substitution pattern.
Figure 11: Alternariol derivatives with the 1-methyl group hydroxylated.
Figure 12: Verrulactones: pseudo-dimeric derivatives of altertenuol and related compounds.
Figure 13: Biaryls formed by reductive lactone opening and/or by decarboxylation.
Figure 14: Altenuene and its diastereomers.
Figure 15: 9-O-Demethylated altenuene diastereomers.
Figure 16: Acetylated and methylated altenuene diastereomers.
Figure 17: Altenuene diastereomers modified with lactic acid, pyruvic acid, or acetone.
Figure 18: Neoaltenuene and related compounds.
Figure 19: Dehydroaltenusin and its derivatives.
Scheme 1: Equilibrium of dehydroaltenusin in polar solvents [278].
Figure 20: Further quinoid derivatives.
Figure 21: Dehydroaltenuenes.
Figure 22: Complex aggregates containing dehydroaltenuene substructures and related compounds.
Figure 23: Dihydroaltenuenes.
Figure 24: Altenuic acids and related compounds.
Figure 25: Cyclopentane- and cyclopentene-fused derivatives.
Figure 26: Cyclopentenone-fused derivatives.
Figure 27: Spiro-fused derivatives and a related ring-opened derivative.
Figure 28: Lactones-fused and lactone-substituted derivatives.
Scheme 2: Biosynthesis of alternariol [324].
Scheme 3: Biosynthesis of alternariol and its immediate successors with the genes involved in the respective ...
Scheme 4: Presumed formation of altenuene and its diastereomers and of botrallin.
Scheme 5: Presumed formation of altenuic acids and related compounds.
Scheme 6: A selection of plausible biosynthetic paths to cyclopenta-fused metabolites. (No stereochemistry is...
Scheme 7: Biomimetic synthesis of alternariol (1) by Harris and Hay [66].
Scheme 8: Total synthesis of alternariol (1) by Subba Rao et al. using a Diels–Alder approach [34].
Scheme 9: Total synthesis of alternariol (1) using a Suzuki strategy by Koch and Podlech [62], improved by Kim et...
Scheme 10: Total synthesis of alternariol (1) using an intramolecular biaryl coupling by Abe et al. [63].
Scheme 11: Total synthesis of altenuene (54) and isoaltenuene (55) by Podlech et al. [249].
Scheme 12: Total synthesis of neoaltenuene (69) by Podlech et al. [35].
Scheme 13: Total synthesis of TMC-264 (79) by Tatsuta et al. [185].
Scheme 14: Total synthesis of cephalosol (99) by Koert et al. [304].
Beilstein J. Org. Chem. 2024, 20, 1436–1443, doi:10.3762/bjoc.20.126
Graphical Abstract
Figure 1: Molecular structure of compound 4a.
Figure 2: Molecular structure of compound 6g.
Scheme 1: Proposed reaction mechanism.
Beilstein J. Org. Chem. 2022, 18, 769–780, doi:10.3762/bjoc.18.77
Graphical Abstract
Scheme 1: Early studies concerning cyclopropene cycloadditions to azomethine ylides and cycloaddition reactio...
Scheme 2: The pilot experiment aimed at studying the cycloaddition reaction between the protonated form of Ru...
Scheme 3: Synthesis of meso-3'-azadispiro[indene-2,2'-bicyclo[3.1.0]hexane-4',2''-indene] derivatives 3b–g vi...
Figure 1: ORTEP representation of the molecular structure of 3e.
Scheme 4: The reaction of protonated Ruhemann's purple (1) with 3-methyl-3-phenylcyclopropene (2j).
Scheme 5: Attempts to carry out the cycloaddition reactions between 3,3-disubstituted cyclopropenes 2k,l and ...
Scheme 6: The reactions of protonated Ruhemann's purple (1) with unstable cyclopropenes 2m–p.
Scheme 7: The acid–base reaction of Ruhemann's purple with hydrochloric acid and relative Gibbs free energy c...
Scheme 8: Plausible mechanism of the 1,3-DC reaction of protonated Ruhemann's purple (1) with 3-methyl-3-phen...
Scheme 9: Plausible mechanism of the 1,3-DC reaction of protonated Ruhemann's purple (1) with 1-chloro-2-phen...
Beilstein J. Org. Chem. 2021, 17, 866–872, doi:10.3762/bjoc.17.72
Graphical Abstract
Scheme 1: Radical addition of Ph2PPPh2 and Ph2P(X)PPh2 to unsaturated C–C bonds.
Scheme 2: The addition of Ph2P(O)PPh2 (1) to 1-octyne (2a).
Scheme 3: Phosphinylphosphination of various terminal alkynes 2 with 1. aIsolated yields. V-40 = 1,1’-azobis(...
Scheme 4: Attempted radical addition to internal alkynes and insight into the addition to 2n.
Scheme 5: A plausible reaction pathway for the radical addition of Ph2P(O)PPh2 to terminal alkynes.
Beilstein J. Org. Chem. 2021, 17, 410–419, doi:10.3762/bjoc.17.37
Graphical Abstract
Scheme 1: Synthetic pathways for the synthesis of 6-substituted 2-triazolylpurine derivatives IV.
Scheme 2: Synthesis of 2,6-bistriazolylpurine derivatives 2a–c.
Scheme 3: Synthesis of 6-alkyloxy-2-triazolylpurine derivatives 3a–f.
Scheme 4: Synthesis of 6-alkyloxy-2-triazolylpurine nucleosides 3g–j.
Scheme 5: 2,6-Bistriazolylpurine derivatives in SNAr reactions with H2O/HO− as nucleophiles.
Scheme 6: Synthesis of C6-substituted 2-triazolylpurine derivatives 5.
Figure 1: Possible tautomeric structures of compounds 5a–d.
Beilstein J. Org. Chem. 2021, 17, 193–202, doi:10.3762/bjoc.17.19
Graphical Abstract
Scheme 1: Structural diversity and synthetic methods of purinylphosphonates. MWI = microwave irradiation; LG ...
Scheme 2: Synthetic routes for the formation of purinylphosphonates 4.
Scheme 3: Synthesis of phosphonates 2, 7, and 8.
Scheme 4: Synthesis of phosphonic acid monoesters 3 and 7–9 as well as phosphonic acid 10.
Figure 1: Screenings of the rate for the ester group cleavage (conversion determined by NMR spectroscopy) in ...
Scheme 5: Synthesis of 2,6-bistriazolylpurine derivatives 6a–i.
Scheme 6: SNAr–Arbuzov reaction between the bistriazolylpurines 6a–i and P(OEt)3.
Figure 2: Single-crystal X-ray analysis of diethyl (9-heptyl-2-(4-phenyl-1H-1,2,3-triazol-1-yl)-9H-purin-6-yl...
Beilstein J. Org. Chem. 2021, 17, 58–82, doi:10.3762/bjoc.17.7
Graphical Abstract
Figure 1: The inthomycins A–C (1–3) and structurally closely related compounds.
Figure 2: Syntheses of inthomycins A–C (1–3).
Scheme 1: The first total synthesis of racemic inthomycin A (rac)-1 by Whiting.
Scheme 2: Moloney’s synthesis of the phenyl analogue of inthomycin C ((rac)-3).
Scheme 3: Moloney’s synthesis of phenyl analogues of inthomycins A (rac-1) and B (rac-2).
Scheme 4: The first total synthesis of inthomycin B (+)-2 by R. J. K. Taylor.
Scheme 5: R. J. K. Taylor’s total synthesis of racemic inthomycin A (rac)-1.
Scheme 6: The first total synthesis of inthomycin C ((+)-3) by R. J. K. Taylor.
Scheme 7: The first total synthesis of naturally occurring inthomycin C ((–)-3) by Ryu et al.
Scheme 8: Preparation of E,E-iododiene (+)-84 and Z,E- iododiene 85a.
Scheme 9: Hatakeyama’s total synthesis of inthomycin A (+)-1 and inthomycin B (+)-2.
Scheme 10: Hatakeyama’s total synthesis of inthomycin C ((–)-3).
Scheme 11: Maulide’s formal synthesis of racemic inthomycin C ((rac)-3).
Scheme 12: Hale’s synthesis of dienylstannane (+)-69 and enyne (+)-82b intermediates.
Scheme 13: Hale’s total synthesis of inthomycin C ((+)-3).
Scheme 14: Hale and Hatakeyama’s resynthesis of (3R)-inthomycin C (−)-3 Mosher esters.
Scheme 15: Reddy’s formal syntheses of inthomycin C (+)-3 and inthomycin C ((−)-3).
Scheme 16: Synthesis of the cross-metathesis precursors (rac)-118 and 121.
Scheme 17: Donohoe’s total synthesis of inthomycin C ((−)-3).
Scheme 18: Synthesis of dienylboronic ester (E,E)-128.
Scheme 19: Synthesis of the alkenyl iodides (Z)- and (E)-130.
Scheme 20: Burton’s total synthesis of inthomycin B ((+)-2).
Scheme 21: Burton’s total synthesis of inthomycin C ((−)-3).
Scheme 22: Burton’s total synthesis of inthomycin A ((+)-1).
Scheme 23: Synthesis of common intermediate (Z)-(+)-143a.
Scheme 24: Synthesis of (Z)-and (E)-selective fragments (+)-145a–c.
Scheme 25: Kim’s total synthesis of inthomycins A (+)-1 and B (+)-2.
Scheme 26: Completion of total synthesis of inthomycin C ((–)-3) by Kim.
Beilstein J. Org. Chem. 2020, 16, 1476–1488, doi:10.3762/bjoc.16.123
Graphical Abstract
Figure 1: Bioactive phenanthridine and phenanthridinium derivatives.
Scheme 1: Synthesis of phenanthrenes by a photo-Pschorr reaction.
Scheme 2: Synthesis of phenanthrenes by a benzannulation reaction.
Scheme 3: Photocatalytic cyclization of α-bromochalcones for the synthesis of phenanthrenes.
Figure 2: Carbon-centered and nitrogen-centered radicals used for the synthesis of phenanthridines.
Scheme 4: General scheme describing the synthesis of phenanthridines from isocyanides via imidoyl radicals.
Scheme 5: Synthesis of substituted phenanthridines involving the intermediacy of electrophilic radicals.
Scheme 6: Photocatalyzed synthesis of 6-β-ketoalkyl phenanthridines.
Scheme 7: Synthesis of 6-substituted phenanthridines through the addition of trifluoromethyl (path a), phenyl...
Scheme 8: Synthesis of 6-(trifluoromethyl)-7,8-dihydrobenzo[k]phenanthridine.
Scheme 9: Phenanthridine syntheses by using photogenerated radicals formed through a C–H bond homolytic cleav...
Scheme 10: Trifluoroacetimidoyl chlorides as starting substrates for the synthesis of 6-(trifluoromethyl)phena...
Scheme 11: Synthesis of phenanthridines via aryl–aryl-bond formation.
Scheme 12: Oxidative conversion of N-biarylglycine esters to phenanthridine-6-carboxylates.
Scheme 13: Photocatalytic synthesis of benzo[f]quinolines from 2-heteroaryl-substituted anilines and heteroary...
Scheme 14: Synthesis of noravicine (14.2a) and nornitidine (14.2b) alkaloids.
Scheme 15: Gram-scale synthesis of the alkaloid trisphaeridine (15.3).
Scheme 16: Synthesis of phenanthridines starting from vinyl azides.
Scheme 17: Synthesis of pyrido[4,3,2-gh]phenanthridines 17.5a–d through the radical trifluoromethylthiolation ...
Scheme 18: The direct oxidative C–H amidation involving amidyl radicals for the synthesis of phenanthridones.
Beilstein J. Org. Chem. 2020, 16, 880–887, doi:10.3762/bjoc.16.79
Graphical Abstract
Scheme 1: Two diversity-oriented strategies: (a) Diversity installed during the construction of the skeleton;...
Figure 1: Structure of four 17-ethynyl-17-hydroxysteroids 1–4 (top) and how they could be used to generate di...
Scheme 2: Synthesis of spirocyclic steroid derivatives by the RCEYM reaction. Conditions: (a) NaH (2 equiv), ...
Figure 2: Structure of metathesis catalysts.
Scheme 3: One-pot RCEYM/Diels–Alder reaction strategy applied to the mestranol and lynestrenol cores. Notes: a...
Figure 3: Rationale for the observed stereochemistry: (a) NOESY correlations observed on compound 16b, showin...
Beilstein J. Org. Chem. 2020, 16, 628–637, doi:10.3762/bjoc.16.59
Graphical Abstract
Figure 1: Chemical structures of the target diazine-based surrogates for the central core of panobinostat.
Figure 2: Docking pose for panobinostat and panobinostat derivatives in the HDAC8 receptor. (a) Overlay of al...
Figure 3: General building blocks for the visualized targets.
Scheme 1: Reaction conditions: a) MeOH, H2SO4 (5 drops), MS 4 Å (2 pieces), 68 °C, 8 h, 81%; b) DIBAL-H (1.2 ...
Scheme 2: Reaction conditions: a) boronic acid 15 (1.3 equiv), PdCl2(PPh3)2 (0.1 equiv), dioxane/H2O (3:1), Na...
Scheme 3: Reaction conditions: a) 5-bromo-2-chloropyrimidine (1 equiv), ethyl formate (1.5 equiv), THF (20 mL...
Scheme 4: Reaction conditions: a) boronic acid 15 (1.3 equiv), PdCl2(PPh3)2 (0.1 equiv), dioxane/H2O (8:2, Na2...
Beilstein J. Org. Chem. 2019, 15, 2113–2132, doi:10.3762/bjoc.15.209
Graphical Abstract
Figure 1: General structure of fulvenes, named according to the number of carbon atoms in their ring. Whilst ...
Figure 2: Generic structures of commonly referenced heteropentafulvenes, named according to the heteroatom su...
Scheme 1: Resonance structures of (a) pentafulvene and (b) heptafulvene showing neutral (1 and 2), dipolar (1a...
Scheme 2: Resonance structures of (a) pentafulvenes and (b) heptafulvenes showing the influence of EDG and EW...
Scheme 3: Reaction of 6,6-dimethylpentafulvene with singlet state oxygen to form an enol lactone via the mult...
Scheme 4: Photosensitized oxygenation of 8-cyanoheptafulvene with singlet state oxygen to afford 1,4-epidioxi...
Figure 3: A representation of HOMO–LUMO orbitals of pentafulvene and the influence of EWG and EDG substituent...
Scheme 5: Reactions of (a) 6,6-dimethylpentafulvene participating as 2π and 4π components in cycloadditions w...
Scheme 6: Proposed mechanism for the [6 + 4] cycloaddition of tropone with dimethylfulvene via an ambimodal [...
Scheme 7: Triafulvene dimerization through the proposed 'head-to-tail' mechanism. The dipolar transition stat...
Scheme 8: Dimerization of pentafulvenes via a Diels–Alder cycloaddition pathway whereby one fulvene acts as a...
Scheme 9: Dimerization of pentafulvenes via frustrated Lewis pair chemistry as reported by Mömming et al. [116].
Scheme 10: Simplified reaction scheme for the formation of kempane from an extended-chain pentafulvene [127].
Scheme 11: The enantioselective (>99% ee), asymmetric, catalytic, intramolecular [6 + 2] cycloaddition of fulv...
Scheme 12: Intramolecular [8 + 6] cycloaddition of the heptafulvene-pentafulvene derivative [22,27].
Scheme 13: Reaction scheme for (a) [2 + 2] cycloaddition of 1,2-diphenylmethylenecyclopropene and 1-diethylami...
Scheme 14: Diels–Alder cycloaddition of pentafulvenes derivatives participating as dienes with (i) maleimide d...
Scheme 15: Generic schemes showing pentafulvenes participating as dienophiles in Diels–Alder cycloadditions wi...
Scheme 16: Reaction of 8,8-dicyanoheptafulvene and styrene derivatives to afford [8 + 2] and [4 + 2] cycloaddu...
Scheme 17: Reaction of 6-aminofulvene and maleic anhydride, showing observed [6 + 2] cycloaddition; the [4 + 2...
Scheme 18: Schemes for Diels–Alder cycloadditions in dynamic combinatorial chemistry reported by Boul et al. R...
Scheme 19: Polymerisation and dynamer formation via Diels–Alder cycloaddition between fulvene groups in polyet...
Scheme 20: Preparation of hydrogels via Diels–Alder cycloaddition with fulvene-conjugated dextran and dichloro...
Scheme 21: Ring-opening metathesis polymerisation of norbornene derivatives derived from fulvenes and maleimid...
Beilstein J. Org. Chem. 2018, 14, 1317–1348, doi:10.3762/bjoc.14.113
Graphical Abstract
Scheme 1: Thermal reaction of sydnones with symmetrical alkynes.
Scheme 2: Reaction of sydnones with strained cycloalkynes.
Scheme 3: Reaction of sydnones with didehydrobenzenes.
Scheme 4: Formation of isomeric pyrazole dicarboxylates.
Scheme 5: Mechanism of thermal cycloaddition between sydnones and alkynes.
Scheme 6: Mechanism of photochemical reaction of sydnones with symmetrical alkynes.
Scheme 7: HOMO–LUMO diagram for thermal [3 + 2]-cycloaddition of sydnones with alkynes.
Scheme 8: Synthetic strategy leading to 1,2-disubstituted pyrazoles.
Scheme 9: Unsuccessful reaction with phenylpropiolic acid.
Scheme 10: Synthetic strategy leading to 1,4,5-trisubstituted pyrazoles.
Scheme 11: Reaction of sydnones carrying in position 4- six-membered 2-N-heterocyclic ring.
Scheme 12: Strain-promoted sydnone alkyne cycloaddition (SPSAC).
Scheme 13: Synthesis of a key intermediate of niraparib.
Scheme 14: Reaction of sydnones with 1,3-/1,4-benzdiyne equivalents.
Scheme 15: Reaction of sydnones with heterocyclic strained cycloalkynes.
Scheme 16: Mono-copper catalyzed cycloaddition reaction.
Scheme 17: Di-copper catalyzed cycloaddition reaction.
Beilstein J. Org. Chem. 2017, 13, 960–987, doi:10.3762/bjoc.13.97
Graphical Abstract
Figure 1: A number of experiments for various optimization algorithms [46].
Figure 2: Symbols used for block and P&ID diagrams.
Scheme 1: Multistep synthesis of olanzapine (Hartwig et al. [10])
Figure 3: (A) Block diagram representation of the process shown in Scheme 1, (B) piping and instrumentation diagram o...
Scheme 2: Multistep flow synthesis for tamoxifen (Murray et al. [11]).
Figure 4: (A) Block diagram representation of the process shown in Scheme 2, (B) piping and instrumentation diagram o...
Figure 5: (A) Block diagram representation of the process shown in Scheme 3, (B) piping and instrumentation diagram o...
Scheme 3: Multistep flow synthesis of rufinamide (Zhang et al. [14]).
Figure 6: (A) Block diagram representation of the process shown in Scheme 4, (B) piping and instrumentation diagram o...
Scheme 4: Multistep synthesis for (±)-Oxomaritidine (Baxendale et al. [9]).
Figure 7: (A) Block diagram representation of the process shown in Scheme 5, (B) piping and instrumentation diagram o...
Scheme 5: Multistep synthesis for ibuprofen (Snead and Jamison [60]).
Scheme 6: Multistep synthesis for cinnarizine and buclizine derivatives (Borukhova et al. [23])
Figure 8: (A) Block diagram representation of the process shown in Scheme 6, (B) piping and instrumentation diagram o...
Scheme 7: Multistep synthesis for (S)-rolipram (Tsubogo et al. [4])
Figure 9: (A) Block diagram representation of the process shown in Scheme 7 (colours for each reactor shows different...
Figure 10: (A) Block diagram representation of the process shown in Scheme 8, (B) piping and instrumentation diagram o...
Scheme 8: Multistep synthesis for amitriptyline (Kupracz and Kirschning [7]).
Beilstein J. Org. Chem. 2016, 12, 863–873, doi:10.3762/bjoc.12.85
Graphical Abstract
Scheme 1: Synthesis of copper complexes 2–6.
Figure 1: X-ray diffraction structure of copper(II) complex 2 with thermal ellipsoids drawn at 30% probabilit...
Figure 2: ORTEP the cationic section of [Cu2(L2)2](PF6)2 (3). Thermal ellipsoids are drawn at the 30% probabi...
Figure 3: ORTEP drawing of [Cu2(L3)2](PF6)2 (4). Thermal ellipsoids are drawn at the 30% probability level. H...
Figure 4: ORTEP drawing of [Cu3(L4)3](PF6)3 (5). Thermal ellipsoids are drawn at the 30% probability level. H...
Figure 5: ORTEP drawing of [Cu3(L5)3](PF6)3 (6). Thermal ellipsoids are drawn at the 30% probability level. H...
Figure 6: Yield vs reaction time of different copper complex. The reaction was carried out in acetonitrile-d3...
Beilstein J. Org. Chem. 2015, 11, 1274–1331, doi:10.3762/bjoc.11.142
Graphical Abstract
Figure 1: General representation of cyclophanes.
Figure 2: cyclophanes one or more with heteroatom.
Figure 3: Metathesis catalysts 12–17 and C–C coupling catalyst 18.
Figure 4: Natural products containing the cyclophane skeleton.
Figure 5: Turriane family of natural products.
Scheme 1: Synthesis of [3]ferrocenophanes through Mannich reaction. Reagents and conditions: (i) excess HNMe2...
Scheme 2: Synthesis of cyclophanes through Michael addition. Reagents and conditions: (i) xylylene dibromide,...
Scheme 3: Synthesis of normuscopyridine analogue 37 through an oxymercuration–oxidation strategy. Reagents an...
Scheme 4: Synthesis of tribenzocyclotriyne 39 through Castro–Stephens coupling reaction. Reagents and conditi...
Scheme 5: Synthesis of cyclophane 43 through Glaser–Eglinton coupling. Reagents and conditions: (i) 9,10-bis(...
Scheme 6: Synthesis of the macrocyclic C-glycosyl cyclophane through Glaser coupling. Reagents and conditions...
Scheme 7: Synthesis of cyclophane-containing complex 49 through Glaser–Eglinton coupling reaction. Reagents a...
Scheme 8: Synthesis of cyclophane 53 through Glaser–Eglinton coupling. Reagents and conditions: (i) K2CO3, ac...
Figure 6: Cyclophanes 54–56 that have been synthesized through Glaser–Eglinton coupling.
Figure 7: Synthesis of tetrasubstituted [2.2]paracyclophane 57 and chiral cyclophyne 58 through Eglinton coup...
Scheme 9: Synthesis of cyclophane through Glaser–Hay coupling reaction. Reagents and conditions: (i) CuCl2 (1...
Scheme 10: Synthesis of seco-C/D ring analogs of ergot alkaloids through intramolecular Heck reaction. Reagent...
Scheme 11: Synthesis of muscopyridine 73 via Kumada coupling. Reagents and conditions: (i) 72, THF, ether, 20 ...
Scheme 12: Synthesis of the cyclophane 79 via McMurry coupling. Reagents and conditions: (i) 75, decaline, ref...
Scheme 13: Synthesis of stilbenophane 81 via McMurry coupling. Reagents and conditions: (i) TiCl4, Zn, pyridin...
Scheme 14: Synthesis of stilbenophane 85 via McMurry coupling. Reagents and conditions: (i) NBS (2 equiv), ben...
Figure 8: List of cyclophanes prepared via McMurry coupling reaction as a key step.
Scheme 15: Synthesis of paracyclophane by cross coupling involving Pd(0) catalyst. Reagents and conditions: (i...
Scheme 16: Synthesis of the cyclophane 112 via the pinacol coupling and 113 by RCM. Reagents and conditions: (...
Scheme 17: Synthesis of cyclophane derivatives 122a–c via Sonogoshira coupling. Reagents and conditions: (i) C...
Scheme 18: Synthesis of cyclophane 130 via Suzuki–Miyaura reaction as a key step. Reagents and conditions: (i)...
Scheme 19: Synthesis of the mycocyclosin via Suzuki–Miyaura cross coupling. Reagents and conditions: (i) benzy...
Scheme 20: Synthesis of cyclophanes via Wurtz coupling reaction Reagents and conditions: (i) PhLi, Et2O, C6H6,...
Scheme 21: Synthesis of non-natural glycophanes using alkyne metathesis. Reagents and conditions: (i) G-I (12)...
Figure 9: Synthesis of cyclophanes via ring-closing alkyne metathesis.
Scheme 22: Synthesis of crownophanes by cross-enyne metathesis. Reagents and conditions: (i) G-II (13), 5 mol ...
Scheme 23: Synthesis of (−)-cylindrocyclophanes A (156) and (−)-cylindrocyclophanes F (155). Reagents and cond...
Scheme 24: Synthesis of cyclophane 159 derivatives via SM cross-coupling and RCM. Reagents and conditions: (i)...
Scheme 25: Sexithiophene synthesis via cross metathesis. Reagents and conditions: (i) 161, Pd(PPh3)4, K2CO3, T...
Scheme 26: Synthesis of pyrrole-based cyclophane using enyne metathesis. Reagents and conditions: (i) Se, chlo...
Scheme 27: Synthesis of macrocyclic derivatives by RCM. Reagents and conditions: (i) G-I/G-II, CH2Cl2, 0.005 M...
Scheme 28: Synthesis of enantiopure β-lactam-based dienyl bis(dihydrofuran) 179. Reagents and conditions: (i) ...
Scheme 29: Synthesis of a [1.1.6]metaparacyclophane derivative 183 via SM cross coupling. Reagents and conditi...
Scheme 30: Synthesis of a [1.1.6]metaparacyclophane derivative 190 via SM cross coupling. Reagents and conditi...
Scheme 31: Template-promoted synthesis of cyclophanes involving RCM. Reagents and conditions: (i) acenaphthene...
Scheme 32: Synthesis of [3.4]cyclophane derivatives 200 via SM cross coupling and RCM. Reagents and conditions...
Figure 10: Examples for cyclophanes synthesized by RCM.
Scheme 33: Synthesis of the longithorone C framework assisted by fluorinated auxiliaries. Reagents and conditi...
Scheme 34: Synthesis of the longithorone framework via RCM. Reagents and conditions: (i) 213, NaH, THF, rt, 10...
Scheme 35: Synthesis of floresolide B via RCM as a key step. Reagents and conditions: (i) G-II (13, 0.1 equiv)...
Scheme 36: Synthesis of normuscopyridine (223) by the RCM strategy. Reagents and condition: (i) Mg, THF, hexen...
Scheme 37: Synthesis of muscopyridine (73) via RCM. Reagents and conditions: (i) 225, NaH, THF, 0 °C to rt, 1....
Scheme 38: Synthesis of muscopyridine (73) via RCM strategy. Reagents and conditions: (i) NaH, n-BuLi, 5-bromo...
Scheme 39: Synthesis of pyridinophane derivatives 223 and 245. Reagents and conditions: (i) PhSO2Na, TBAB, CH3...
Scheme 40: Synthesis of metacyclophane derivatives 251 and 253. Reagents and conditions: (i) 240, NaH, THF, rt...
Scheme 41: Synthesis of normuscopyridine and its higher analogues. Reagents and conditions: (i) alkenyl bromid...
Scheme 42: Synthesis of fluorinated ferrocenophane 263 via a [2 + 2] cycloaddition. Reagents and conditions: (...
Scheme 43: Synthesis of [2.n]metacyclophanes 270 via a [2 + 2] cycloaddition. Reagents and conditions: (i) Ac2...
Scheme 44: Synthesis of metacyclophane 273 by a [2 + 2 + 2] co-trimerization. Reagents and conditions: (i) [Rh...
Scheme 45: Synthesis of paracyclophane 276 via a [2 + 2 + 2] cycloaddition reaction. Reagents and conditions: ...
Scheme 46: Synthesis of cyclophane 278 via a [2 + 2 + 2] cycloaddition reaction. Reagents and conditions: (i) ...
Scheme 47: Synthesis of cyclophane 280 via a [2 + 2 + 2] cycloaddition. Reagents and conditions: (i) [(Rh(cod)(...
Scheme 48: Synthesis of taxane framework by a [2 + 2 + 2] cycloaddition. Reagents and conditions: (i) Cp(CO)2 ...
Scheme 49: Synthesis of cyclophane 284 and 285 via a [2 + 2 + 2] cycloaddition reaction. Reagents and conditio...
Scheme 50: Synthesis of pyridinophanes 293a,b and 294a,b via a [2 + 2 + 2] cycloaddition. Reagents and conditi...
Scheme 51: Synthesis of pyridinophanes 296 and 297 via a [2 + 2 + 2] cycloaddition. Reagents and conditions: (...
Scheme 52: Synthesis of triazolophane by a 1,3-dipolar cycloaddition. Reagents and conditions: (i) propargyl b...
Scheme 53: Synthesis of glycotriazolophane 309 by a click reaction. Reagents and conditions: (i) LiOH, H2O, Me...
Figure 11: Cyclophanes 310 and 311 prepared via click chemistry.
Scheme 54: Synthesis of cyclophane via the Dötz benzannulation. Reagents and conditions: (i) THF, 100 °C, 12 h...
Scheme 55: Synthesis of [6,6]metacyclophane by a Dötz benzannulation. Reagents and conditions: (i) THF, 100 °C...
Scheme 56: Synthesis of cyclophanes by a Dötz benzannulation. Reagents and conditions: (i) THF, 65 °C, 3 h; (i...
Scheme 57: Synthesis of muscopyridine (73) via an intramolecular DA reaction of ketene. Reagents and condition...
Scheme 58: Synthesis of bis[10]paracyclophane 336 via Diels–Alder reaction. Reagents and conditions: (i) DMAD,...
Scheme 59: Synthesis of [8]paracyclophane via DA reaction. Reagents and conditions: (i) maleic anhydride, 3–5 ...
Scheme 60: Biomimetic synthesis of (−)-longithorone A. Reagents and conditions: (i) Me2AlCl, CH2Cl2, −20 °C, 7...
Scheme 61: Synthesis of sporolide B (349) via a [4 + 2] cycloaddition reaction. Reagents and conditions: (i) P...
Scheme 62: Synthesis of the framework of (+)-cavicularin (352) via a [4 + 2] cycloaddition. Reagents and condi...
Scheme 63: Synthesis of oxazole-containing cyclophane 354 via Beckmann rearrangement. Reagents and conditions:...
Scheme 64: Synthesis of cyclophanes 360a–c via benzidine rearrangement. Reagents and conditions: (i) 356a–d, K2...
Scheme 65: Synthesis of cyclophanes 365a–c via benzidine rearrangement. Reagents and conditions: (i) BocNHNH2,...
Scheme 66: Synthesis of metacyclophane 367 via Ciamician–Dennstedt rearrangement. Reagents and conditions: (i)...
Scheme 67: Synthesis of cyclophane by tandem Claisen rearrangement and RCM as key steps. Reagents and conditio...
Scheme 68: Synthesis of cyclophane derivative 380. Reagents and conditions: (i) K2CO3, CH3CN, allyl bromide, r...
Scheme 69: Synthesis of metacyclophane via Cope rearrangement. Reagents and conditions: (i) MeOH, NaBH4, rt, 1...
Scheme 70: Synthesis of cyclopropanophane via Favorskii rearrangement. Reagents and conditions: (i) Br2, CH2Cl2...
Scheme 71: Cyclophane 389 synthesis via photo-Fries rearrangement. Reagents and conditions: (i) DMAP, EDCl/CHCl...
Scheme 72: Synthesis of normuscopyridine (223) via Schmidt rearrangement. Reagents and conditions: (i) ethyl s...
Scheme 73: Synthesis of crownophanes by tandem Claisen rearrangement. Reagents and conditions: (i) diamine, Et3...
Scheme 74: Attempted synthesis of cyclophanes via tandem Claisen rearrangement and RCM. Reagents and condition...
Scheme 75: Synthesis of muscopyridine via alkylation with 2,6-dimethylpyridine anion. Reagents and conditions:...
Scheme 76: Synthesis of cyclophane via Friedel–Craft acylation. Reagents and conditions: (i) CS2, AlCl3, 7 d, ...
Scheme 77: Pyridinophane 418 synthesis via Friedel–Craft acylation. Reagents and conditions: (i) 416, AlCl3, CH...
Scheme 78: Cyclophane synthesis involving the Kotha–Schölkopf reagent 421. Reagents and conditions: (i) NBS, A...
Scheme 79: Cyclophane synthesis involving the Kotha–Schölkopf reagent 421. Reagents and conditions: (i) BEMP, ...
Scheme 80: Cyclophane synthesis by coupling with TosMIC. Reagents and conditions: (i) (a) ClCH2OCH3, TiCl4, CS2...
Scheme 81: Synthesis of diaza[32]cyclophanes and triaza[33]cyclophanes. Reagents and conditions: (i) DMF, NaH,...
Scheme 82: Synthesis of cyclophane 439 via acyloin condensation. Reagents and conditions: (i) Na, xylene, 75%;...
Scheme 83: Synthesis of multibridged binuclear cyclophane 442 by aldol condensation. Reagents and conditions: ...
Scheme 84: Synthesis of various macrolactones. Reagents and conditions: (i) iPr2EtN, DMF, 77–83%; (ii) TBDMSCl...
Scheme 85: Synthesis of muscone and muscopyridine via Yamaguchi esterification. Reagents and conditions: (i) 4...
Scheme 86: Synthesis of [5]metacyclophane via a double elimination reaction. Reagents and conditions: (i) LiBr...
Figure 12: Cyclophanes 466–472 synthesized via Hofmann elimination.
Scheme 87: Synthesis of cryptophane via Baylis–Hillman reaction. Reagents and conditions: (i) methyl acrylate,...
Scheme 88: Synthesis of cyclophane 479 via double Chichibabin reaction. Reagents and conditions: (i) excess 478...
Scheme 89: Synthesis of cyclophane 483 via double Chichibabin reaction. Reagents and conditions: (i) 481, OH−;...
Scheme 90: Synthesis of cyclopeptide via an intramolecular SNAr reaction. Reagents and conditions: (i) TBAF, T...
Scheme 91: Synthesis of muscopyridine (73) via C-zip ring enlargement reaction. Reagents and conditions: (i) H...
Figure 13: Mechanism of the formation of compound 494.
Scheme 92: Synthesis of indolophanetetraynes 501a,b using the Nicholas reaction as a key step. Reagents and co...
Scheme 93: Synthesis of cyclophane via radical cyclization. Reagents and conditions: (i) cyclododecanone, phen...
Scheme 94: Synthesis of (−)-cylindrocyclophanes A (156) and (−)-cylindrocyclophanes F (155). Reagents and cond...
Scheme 95: Cyclophane synthesis via Wittig reaction. Reagents and conditions: (i) LiOEt (2.1 equiv), THF, −78 ...
Figure 14: Representative examples of cyclophanes synthesized via Wittig reaction.
Scheme 96: Synthesis of the [6]paracyclophane via isomerization of Dewar benzene. Reagents and conditions: (i)...
Beilstein J. Org. Chem. 2015, 11, 576–582, doi:10.3762/bjoc.11.63
Graphical Abstract
Scheme 1: Hetero-Diels–Alder reaction of thiobenzophenone (1a) with dimethyl acetylenedicarboxylate (2a) [10].
Scheme 2: Synthesis of polycyclic thiopyrans via the hetero-Diels–Alder reaction/1,3-hydrogen shift sequence.
Figure 1: ORTEP Plot [19] of the molecular structure of 4b, drawn using 50% probability displacement ellipsoids.
Scheme 3: Reactions of aryl/hetaryl thioketones with methyl propiolate (Table 1).
Scheme 4: Oxidation of selected thiopyrans 4 and 5 to give the corresponding sulfones.
Figure 2: ORTEP Plot [19] of the molecular structure of one of the symmetry-independent molecules of 6d, drawn us...
Beilstein J. Org. Chem. 2014, 10, 1159–1165, doi:10.3762/bjoc.10.116
Graphical Abstract
Figure 1: The phacelocarpus 2-pyrones 1 and 2.
Scheme 1: Generalised O-functionalisation of 6-alkyl-4-hydroxy-2-pyrones 3.
Scheme 2: Synthesis of alkylated 2-pyrones 3b–e.
Scheme 3: Michael addition of 3a to allene 8 and internal alkyne 10.
Beilstein J. Org. Chem. 2014, 10, 1064–1096, doi:10.3762/bjoc.10.106
Graphical Abstract
Scheme 1: Synthesis of P-stereogenic phosphines 5 using menthylphosphinite borane diastereomers 2.
Scheme 2: Enantioselective synthesis of chiral phosphines 10 with ephedrine as a chiral auxiliary.
Scheme 3: Chlorophosphine boranes 11a as P-chirogenic electrophilic building blocks.
Scheme 4: Monoalkylation of phenylphosphine borane 15 with methyl iodide in the presence of Cinchona alkaloid...
Scheme 5: Preparation of tetraphosphine borane 19.
Scheme 6: Using chiral chlorophosphine-boranes 11b as phosphide borane 20 precursors.
Scheme 7: Nickel-catalyzed cross-coupling (dppe = 1,2-bis(diphenylphosphino)ethane).
Scheme 8: Pd-catalyzed cross-coupling reaction with organophosphorus stannanes 30.
Scheme 9: Copper iodide catalyzed carbon–phosphorus bond formation.
Scheme 10: Thermodynamic kinetic resolution as the origin of enantioselectivity in metal-catalyzed asymmetric ...
Scheme 11: Ru-catalyzed asymmetric phosphination of benzyl and alkyl chlorides 35 with HPPhMe (36a, PHOX = pho...
Scheme 12: Pt-catalyzed asymmetric alkylation of secondary phosphines 36b.
Scheme 13: Different adducts 43 can result from hydrophosphination.
Scheme 14: Pt-catalyzed asymmetric hydrophosphination.
Scheme 15: Intramolecular hydrophosphination of phosphinoalkene 47.
Scheme 16: Organocatalytic asymmetric hydrophosphination of α,β-unsaturated aldehydes 59.
Scheme 17: Preparation of phosphines using zinc organometallics.
Scheme 18: Preparation of alkenylphosphines 71a from alkenylzirconocenes 69 (dtc = N,N-diethyldithiocarbamate,...
Scheme 19: SNAr with P-chiral alkylmethylphosphine boranes 13c.
Scheme 20: Synthesis of QuinoxP 74 (TMEDA = tetramethylethylenediamine).
Scheme 21: Pd-Mediated couplings of a vinyl triflate 76 with diphenylphosphine borane 13e.
Figure 1: Menthone (83) and camphor (84) derived chiral phosphines.
Scheme 22: Palladium-catalyzed cross-coupling reaction of vinyl tosylates 85 and 87 with diphenylphosphine bor...
Scheme 23: Attempt for the enantioselective palladium-catalyzed C–P cross-coupling reaction between an alkenyl...
Scheme 24: Enol phosphates 88 as vinylic coupling partners in the palladium-catalyzed C–P cross-coupling react...
Scheme 25: Nickel-catalyzed cross-coupling in the presence of zinc (dppe = 1,2-bis(diphenylphosphino)ethane).
Scheme 26: Copper-catalyzed coupling of secondary phosphines with vinyl halide 94.
Scheme 27: Palladium-catalyzed cross-coupling of aryl iodides 97 with organoheteroatom stannanes 30.
Scheme 28: Synthesis of optically active phosphine boranes 100 by cross-coupling with a chiral phosphine boran...
Scheme 29: Palladium-catalyzed P–C cross-coupling reactions between primary or secondary phosphines and functi...
Scheme 30: Enantioselective synthesis of a P-chirogenic phosphine 108.
Scheme 31: Enantioselective arylation of silylphosphine 110 ((R,R)-Et-FerroTANE = 1,1'-bis((2R,4R)-2,4-diethyl...
Scheme 32: Nickel-catalyzed arylation of diphenylphosphine 25d.
Scheme 33: Nickel-catalyzed synthesis of (R)-BINAP 116 (dppe = 1,2-bis(diphenylphosphino)ethane, DABCO = 1,4-d...
Scheme 34: Nickel-catalyzed cross-coupling between aryl bromides 119 and diphenylphosphine (25d) (dppp = 1,3-b...
Scheme 35: Stereocontrolled Pd(0)−Cu(I) cocatalyzed aromatic phosphorylation.
Scheme 36: Preparation of alkenylphosphines by hydrophosphination of alkynes.
Scheme 37: Palladium and nickel-catalyzed addition of P–H to alkynes 125a.
Scheme 38: Palladium-catalyzed asymmetric hydrophosphination of an alkyne 128.
Scheme 39: Ruthenium catalyzed hydrophosphination of propargyl alcohols 132 (cod = 1,5-cyclooctadiene).
Scheme 40: Cobalt-catalyzed hydrophosphination of alkynes 134a (acac = acetylacetone).
Scheme 41: Tandem phosphorus–carbon bond formation–oxyfunctionalization of substituted phenylacetylenes 125c (...
Scheme 42: Organolanthanide-catalyzed intramolecular hydrophosphination/cyclization of phosphinoalkynes 143.
Scheme 43: Hydrophosphination of alkynes 134c catalyzed by ytterbium-imine complexes 145 (hmpa = hexamethylpho...
Scheme 44: Calcium-mediated hydrophosphanylation of alkyne 134d.
Scheme 45: Formation and substitution of bromophosphine borane 151.
Scheme 46: General scheme for a nickel or copper catalyzed cross-coupling reaction.
Scheme 47: Copper-catalyzed synthesis of alkynylphosphines 156.
Beilstein J. Org. Chem. 2013, 9, 2641–2659, doi:10.3762/bjoc.9.300
Graphical Abstract
Figure 1: Structures of limonene, carvone and thalidomide.
Figure 2: Structure of Garner’s aldehyde.
Scheme 1: (a) i) Boc2O, 1.0 N NaOH (pH >10), dioxane, +5 °C → rt; ii) MeI, K2CO3, DMF, 0 °C → rt (86% over tw...
Scheme 2: (a) AcCl, MeOH, 0 °C → reflux (99%); (b) i) (Boc)2O, Et3N, THF, 0 °C → rt → 50 °C (89%); ii) Me2C(O...
Scheme 3: (a) LiAlH4, THF, rt (93–96%); (b) (COCl)2, DMSO, iPr2NEt, CH2Cl2, −78 °C → −55 °C (99%).
Scheme 4: The Koskinen procedure for the preparation of Garner’s aldehyde. (a) i) AcCl, MeOH, 0 °C → 50 °C (9...
Scheme 5: Burke’s synthesis of Garner’s aldehyde. BDP - bis(diazaphospholane).
Figure 3: Structures of some iminosugars (7, 9), peptide antibiotics (8) and sphingosine (10) and pachastriss...
Scheme 6: Use of Garner’s aldehyde 1 in multistep synthesis.
Scheme 7: Explanation of the anti- and syn-selectivity in the nucleophilic addition reaction.
Scheme 8: Herold’s method: (a) Lithium 1-pentadecyne, HMPT, THF, −78 °C (71%); (b) Lithium 1-pentadecyne, ZnBr...
Scheme 9: (a) Ethyl lithiumpropiolate, HMPT, THF, −78 °C; (b) (S)- or (R)-MTPA, DCC, DMAP, THF, rt (18, 81%) ...
Scheme 10: Coleman’s selectivity studies and their transition state model for the co-ordinated delivery of the...
Scheme 11: (a) PhMgBr, THF, −78 °C → 0 °C [62] or (a) PhMgBr, Et2O, 0 °C [63].
Scheme 12: (a) cat. RhCl3·3H2O, cat. 26, NaOMe, Ph-B(OH)2, aq DME, 80 °C (24, 71%); (b) cat. RhCl3·3H2O, cat. ...
Scheme 13: Lithiated dithiane (3 equiv), CuI (0.3 equiv), BF3·Et2O (6 equiv), THF, −50 °C, 12 h (70%).
Scheme 14: Addition reaction reported by Lam et al. (a) 1-Hexyne, n-BuLi, THF, −15 °C or −40 °C.
Scheme 15: (a) n-BuLi, HMPT, toluene, −78 °C → rt (85%); (b) n-BuLi, ZnCl2, toluene/Et2O, −78 °C → rt (65%).
Scheme 16: (a) n-BuLi, 34, THF, −40 °C [69]; (b) n-BuLi, 35, THF, −78 °C → rt (80%) [70]; (c) n-BuLi, 35, HMPT, THF, −...
Scheme 17: (a) cat. Rh(acac)(CO)2, 42, THF, 40 °C (74%).
Scheme 18: (a) 1-PropynylMgBr, CuI, THF, Me2S, −78 °C (95%); (b) Ethynyltrimethylsilane, EtMgBr, CuI, THF, Me2...
Scheme 19: (a) cat. 50, toluene, 0 °C (52%); (b) cat. 51, toluene, 0 °C (51%); (c) cat. 52, toluene, 0 °C (50%...
Scheme 20: (a) (iPr)3SiH, cat. Ni(COD)2, dimesityleneimidazolium·HCl, t-BuOK, THF, rt.
Scheme 21: (a) Cp2Zr(H)Cl, cat. AgAsF6, CH2Cl2, rt; (b) Cp2Zr(H)Cl, 1-pentadecyne, cat. ZnBr2 in THF for anti-...
Scheme 22: (a) i) 31, n-BuLi, THF, −78 °C; ii) (S)-1, THF, −78 °C; (b) Red-Al, THF, 0 °C.
Scheme 23: (a) 61, n-BuLi, DMPU, toluene, −78 °C, then (S)-1, toluene, −95 °C (57%); (b) 61, n-BuLi, ZnCl2, to...
Scheme 24: Olefin A as an intermediate in natural product synthesis.
Scheme 25: (a) Ph3(Me)PBr, KH, benzene (66%, rac-64) or (b) AlMe3, Zn, CH2I2, THF (76%) [101]; (c) Ph3(Me)PBr, n-Bu...
Scheme 26: (a) Benzene, rt (82%) [108]; (b) K2CO3, MeOH (85%) [89]; (c) iPrOH, [Ir(COD)Cl]2, PPh3, THF, rt (81%) [114].
Scheme 27: Mechanism of the Still–Gennari modification of the HWE reaction leading to both olefin isomers.
Beilstein J. Org. Chem. 2013, 9, 1969–1976, doi:10.3762/bjoc.9.233
Graphical Abstract
Scheme 1: Gold-catalyzed reactions of oxabicyclic alkenes with electron-deficient terminal alkynes.
Figure 1: Gold complexes used in this reaction.
Scheme 2: The reaction with terminal alkyne 2i as a substrate.
Scheme 3: The reaction with naphthalen-1-ol (5) as a substrate.
Scheme 4: The proposed mechanism for Au(I)-catalyzed reaction.
Beilstein J. Org. Chem. 2013, 9, 846–851, doi:10.3762/bjoc.9.97
Graphical Abstract
Figure 1: Molecular structure of the spiro compound 1c.
Figure 2: Molecular structure of the spiro compound 1h.
Figure 3: Molecular structure of spiro compound 2b.
Figure 4: Molecular structure of spiro compound 3b.
Scheme 1: The proposed mechanism for the domino reaction.
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, 1839–1843, doi:10.3762/bjoc.8.211
Graphical Abstract
Scheme 1: Synthesis of polysubstituted tetrahydroquinolines 1a–1m.
Figure 1: Molecular structure of compound 1c.
Scheme 2: The proposed mechanism of domino Povarov reaction.
Beilstein J. Org. Chem. 2011, 7, 601–605, doi:10.3762/bjoc.7.70
Graphical Abstract
Scheme 1: Conversion of propargyl acetate 1 to spirooxindole 2 containing the core framework of welwitindolin...
Scheme 2: Preparation of enantiopure propargyl acetate 7 (R = Ac).
Figure 1: Chiral NMR shift analysis of propargyl acetate 7.
Figure 2: Chiral NMR shift analysis of allenyloxindole 8.
Scheme 3: Microwave irradiation of allenyloxindole 8.
Figure 3: Chiral NMR shift analysis of spirooxindole 9.
Figure 4: Thermally generated biradical intermediate 10.
Beilstein J. Org. Chem. 2008, 4, No. 38, doi:10.3762/bjoc.4.38
Graphical Abstract
Scheme 1: Cyclopropylmethyl–homoallyl and nortricyclyl–norbornenyl radical systems.
Scheme 2: Deoxygenation-rearrangement-electrophile trapping.
Figure 1: Radical SOMO/α-nitrogen lone-pair interaction in the rearranged radical 7.
Figure 2: Other products obtained from xanthate 5 by tandem deoxygenation–rearrangement–electrophile trapping....
Scheme 3: Asymmetric hydroboration–oxidation of alkenes 14, 16 and 18.
Scheme 4: Deoxygenation–rearrangement–isomerisation of xanthates 20 and 23.
Scheme 5: Deoxygenation–rearrangement–electrophile trapping of xanthates 20 and 23.
Scheme 6: 2-Azabenzonorbornene as a masked pyrrolidine.
Scheme 7: Ring-opening–hydration–oxidation of azacycle 8.
Scheme 8: Preparation of trisubstituted pyrrolidine (+)-36.
Scheme 9: Preparation of pyrrolidine diester (+)-35 from Vince’s lactam 37.
Scheme 10: Acid-catalysed ring-opening–oxidation of azacycle (+)-8.
Scheme 11: Birch reduction of (+)-8 and 10.