Synthesis of Highly Substituted Cyclopentenones via the [4 + 1] Cycloaddition of Nucleophilic Carbenes and Vinyl Ketenes
作者:James H. Rigby、Zhengqiang Wang
DOI:10.1021/ol0272141
日期:2003.2.1
[reaction: see text] Vinylketenes have been shown to undergo [4 + 1] cycloaddition with a variety of nucleophilic carbenes to deliver highly substituted cyclopentenones as products.
Reactions of (Trialkylsilyl)vinylketenes with Lithium Ynolates: A New Benzannulation Strategy
作者:Wesley F. Austin、Yongjun Zhang、Rick L. Danheiser
DOI:10.1021/ol051307b
日期:2005.9.1
(Trialkylsilyl)vinylketenes react with lithium ynolates to produce highly substituted phenols in a new benzannulation strategy that proceeds via the 6 pi electrocyclization of an intermediate 3-(oxido)dienylketene.
(Trialkylsilyl)vinylketenes: Synthesis and Application as Diene Components in Diels−Alder Cycloadditions
作者:Jennifer L. Loebach、Dawn M. Bennett、Rick L. Danheiser
DOI:10.1021/jo981289u
日期:1998.11.1
New strategies for the synthesis of (trialkylsilyl)vinylketenes ("TAS-vinylketenes") are described based on the photochemical Wolff rearrangement of alpha-silyl-alpha'-diazo-alpha,beta-unsaturated ketones and the 4 pi electrocyclic ring opening of cyclobutenones. These remarkably robust vinylketenes undergo highly regioselective [4 + 2] cycloadditions with reactive olefinic and acetylenic dienophiles to produce highly substituted cyclohexenones and phenols in which the ketene carbonyl dominates in controlling the regiochemical course of the reaction. The stereochemical course of these cycloadditions follows the Alder endo rule, as illustrated in the reaction of nitropropene with TBS-vinylketene 22.
The Reaction of (Trialkylsilyl)vinylketenes with Carbenoid Reagents: A New [4+1] Annulation Route to Cyclopentenones
作者:Jennifer L. Loebach、Dawn M. Bennett、Rick L. Danheiser
DOI:10.1021/ja982101r
日期:1998.9.1
A benzannulation strategy for the synthesis of phenols and heteroaromatic compounds based on the reaction of (trialkylsilyl)vinylketenes with lithium ynolates
作者:Wesley F. Austin、Yongjun Zhang、Rick L. Danheiser
DOI:10.1016/j.tet.2007.10.113
日期:2008.1
(Trialkylsilyl)vinylketenes react with lithium ynolates to generate 3-(oxido)dienylketenes, which undergo rapid 6π-electrocyclization. The ultimate products of this benzannulation are highly substituted resorcinol monosilyl ethers, which are formed via a [1,3] carbon to oxygen silyl group shift. Further transformations of the benzannulation products are described providing efficient access to ortho-benzoquinones