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Search for "alkyne–carbonyl metathesis" in Full Text gives 2 result(s) in Beilstein Journal of Organic Chemistry.
Strategies in the synthesis of dibenzo[b,f]heteropines
- David I. H. Maier,
- Barend C. B. Bezuidenhoudt and
- Charlene Marais
Beilstein J. Org. Chem. 2023, 19, 700–718, doi:10.3762/bjoc.19.51
- ) chloride (Scheme 26). Alkyne–carbonyl metathesis is proposed to proceed via [2 + 2] cycloaddition and –reversion steps, catalysed by a Brønsted or Lewis acid, with the catalyst proposed to form a σ-complex with the carbonyl group and/or a π-complex with the alkyne [68]. 3.7 Hydroarylation The construction
Graphical Abstract
Figure 1: Dibenzo[b,f]azepine (1a), -oxepine (1b) and -thiepine (1c) as examples of dibenzo[b,f]heteropines (1...
Figure 2: Selected pharmaceuticals with the dibenzo[b,f]azepine skeleton.
Figure 3: Examples of 10,11-dihydrodibenzo[b,f]azepine-based ligands.
Figure 4: The dibenzo[b,f]azepine moiety in dyes with properties suitable for the use in organic light emitti...
Figure 5: Selective bioactive natural products (13–18) containing the dibenzo[b,f]oxepine scaffold and Novart...
Scheme 1: Retrosynthetic approach to 5H-dibenzo[b,f]azepine (1a) from nitrotoluene (22).
Scheme 2: Oxidative coupling of o-nitrotoluene (22) and reduction of 2,2'-dinitrobibenzyl (21) to form 2,2'-d...
Scheme 3: Synthesis of 10,11-dihydro-5H-dibenzo[b,f]azepine (2a) via amine condensation.
Scheme 4: Catalytic reduction of 10,11-dihydro-5H-dibenzo[b,f]azepine (2a).
Scheme 5: The Wagner–Meerwein rearrangement of acridin-9-ylmethanol (23) into 5H-dibenzo[b,f]azepine (1a).
Scheme 6: Oxidative ring expansion of 2-(9-xanthenyl)malonates 24.
Scheme 7: Ring expansion via C–H functionalisation.
Scheme 8: The synthesis of fluorinated 5H-dibenzo[b,f]azepine 38 from isatin (32).
Scheme 9: The synthesis of substituted dibenzo[b,f]azepines 43 from indoles 39.
Scheme 10: Retrosynthetic pathways to dibenzo[b,f]azepines via Buchwald–Hartwig amination.
Scheme 11: Synthesis of dibenzo[b,f]oxepine 54 and -azepine 55 derivatives via (i) Heck reaction and (ii) Buch...
Scheme 12: Double Buchwald–Hartwig amination and thioetherification in the synthesis of tricyclic azepines 60 ...
Scheme 13: Double Buchwald–Hartwig amination towards substituted dibenzoazepines 62.
Scheme 14: Double Buchwald–Hartwig amination towards 10,11-dihydro-5H-dibenzo[b,f]azepine derivatives 71.
Scheme 15: One-pot Suzuki coupling–Buchwald–Hartwig amination.
Scheme 16: One-pot Rh/Pd-catalysed synthesis of dihydropyridobenzazepines.
Scheme 17: A retrosynthetic pathway to dibenzo[b,f]azepines via Mizoroki–Heck reaction.
Scheme 18: One-pot domino Pd-catalyzed Mizoroki–Heck–Buchwald–Hartwig synthesis of dibenzo[b,f]azepines.
Scheme 19: Dibenzo[b,f]thiapine and -oxepine synthesis via SNAr (thio)etherification, Wittig methylenation and...
Scheme 20: A retrosynthetic pathway to dibenzo[b,f]oxepines via Ullmann coupling.
Scheme 21: Ullmann-type coupling in dibenzo[b,f]oxepine synthesis.
Scheme 22: Wittig reaction and Ullmann coupling as key steps in dihydrobenz[b,f]oxepine synthesis.
Scheme 23: Pd-catalysed dibenzo[b,f]azepine synthesis via norbornene azepine intermediate 109.
Scheme 24: A simple representation of olefin metathesis resulting in transalkylidenation.
Scheme 25: Ring-closing metathesis as key step in the synthesis of dibenzo[b,f]heteropines.
Scheme 26: Alkyne–aldehyde metathesis in the synthesis of dibenzo[b,f]heteropines.
Scheme 27: Hydroarylation of 9-(2-alkynylphenyl)-9H-carbazole derivatives.
Scheme 28: Oxidative coupling of bisphonium ylide intermediate to give pacharin (13).
Scheme 29: Preparation of 10,11-dihydrodibenzo[b,f]heteropines via intramolecular Wurtz reaction.
Scheme 30: Phenol deprotonation and intramolecular etherification in the synthesis of bauhinoxepine J.
Figure 6: Functionalisation of dibenzo[b,f]azepine.
Scheme 31: Palladium-catalysed N-arylation of dibenzo[b,f]azepine.
Scheme 32: Cu- and Ni-catalysed N-arylation.
Scheme 33: N-Alkylation of dibenzo[b,f]azepine (1a) and dihydrodibenzo[b,f]azepine (2a).
Scheme 34: Preparation of methoxyiminosilbene.
Scheme 35: Synthesis of oxcarbazepine (153) from methoxy iminostilbene 151.
Scheme 36: Ring functionalisation of dihydrodibenzo[b,f]azepine.
Construction of cyclic enones via gold-catalyzed oxygen transfer reactions
- Leping Liu,
- Bo Xu and
- Gerald B. Hammond
Beilstein J. Org. Chem. 2011, 7, 606–614, doi:10.3762/bjoc.7.71
- - or Lewis acid-catalyzed oxygen transfer from carbonyl to carbon–carbon triple bond, the so-called alkyne–carbonyl metathesis, has attracted much attention because this atom economical transformation generates α,β-unsaturated carbonyl derivatives which are of great interest in synthetic organic
- chemistry. This mini-review focuses on the most recent achievements on gold-catalyzed oxygen transfer reactions of tethered alkynones, diynes or alkynyl epoxides to cyclic enones. The corresponding mechanisms for the transformations are also discussed. Keywords: alkyne–carbonyl metathesis; cyclic enones
- oxygen transfer from a carbonyl group to a carbon–carbon triple bond, the so-called alkyne–carbonyl metathesis. This methodology has sparked the attention of the synthetic community, because it could serve as an efficient and atom-economic alternative to the Wittig reaction by the formation of a new
Graphical Abstract
Scheme 1: Lewis acid or Brønsted acid-catalyzed alkyne–carbonyl metathesis and a proposed [2 + 2] intermediat...
Scheme 2: Gold-catalyzed cyclization of internal alkynyl ketones.
Scheme 3: Proposed [2 + 2] mechanism for the cyclization of alkynyl ketones.
Scheme 4: Gold-catalyzed cyclization of terminal alkynyl ketones.
Scheme 5: Gold-catalyzed tandem oxygen transfer/Nazarov cyclizations.
Scheme 6: TfOH-mediated cyclization of alkynyl ketones.
Scheme 7: Gold-catalyzed cyclizations of 2-alkynyl-1,5-diketones.
Scheme 8: Designed isotopic labeling experiment for mechanistic studies.
Scheme 9: 18O isotopic experiments.
Scheme 10: B2PLYP/6-311+G(d,p)//B2PLYP/6-31G(d) computed reaction profile, relative energies in kcal/mol.
Scheme 11: Gold-catalyzed cyclization of tethered alkynyl arylaldehydes.
Scheme 12: Gold-catalyzed cyclization of terminal diynes.
Scheme 13: Proposed hydrolysis/cyclization mechanism.
Scheme 14: Gold-catalyzed cyclization of internal diynes.
Scheme 15: Proposed solvolysis/cyclization mechanism.
Scheme 16: Gold-catalyzed cyclization of alkynyl epoxides and the 18O isotopic labeling experiment.
Scheme 17: Proposed oxygen transfer mechanism.
Scheme 18: Gold or silver-catalyzed cyclization of alkynyl epoxides and the corresponding deuterium labeling e...
