Synthesis of thiochromans by means of a (4++2) polar cycloaddition of m-tolylthiomethyl chloride with substituted alkenes: A simple synthesis of (.+-.)-cuparene and related sesquiterpenoids.
Lithium–liquid ammonia mediated carbocyclisation of δ,ε-unsaturated esters: annulation of cyclopentanones
作者:A. Srikrishna、S.S.V. Ramasastry
DOI:10.1016/j.tetlet.2003.10.164
日期:2004.1
Lithium–liquid ammonia mediated carbanion cyclisation of δ,ε-unsaturated esters leading to cyclopentanes, fused as well as spiro, via annulation is described.
描述了锂-液氨介导的δ,ε-不饱和酯的碳环化,通过环化反应生成环戊烷,以及稠合和螺环化。
Metal Mediated One-Pot Synthesis of Cyclopentanones from Allyl Vinyl Ethers or Diallyl Ethers via Tandem Claisen Rearrangement and Hydroacylation
Cyclopentanones 3 and 7 are generated in a one-pot procedure from allyl vinyl ethers 1 and diallyl ethers 4, respectively. The conversion is carried out in the presence of RhCl(cod)(dppe) or RuCl2(PPh3)3 at elevated temperatures and involves a sequence of aliphatic Claisen rearrangement and intramolecular hydroacylation of the pent-4-enals generated as intermediates. The diallyl ethers 4 undergo an additional double-bond isomerization prior to the Claisen rearrangement.
Synthese des (±)-(α)-cuparenons durch hydrocarbonylierende cyclisierung von 1,4-dienen
作者:Peter Eilbracht、Erika Balß、Michael Acker
DOI:10.1016/s0040-4039(01)91541-2
日期:——
Synthesis of title compound via hydrocarbonylating cyclization of 1,4-dienes is reported
报道了通过1,4-二烯的烃基化环合反应合成标题化合物
A radical cyclisation based strategy to cuparenoids; synthesis of (±)-α-cuparenone, (±)-epilaurene and laurenes
作者:A. Srikrishna、G. Sundarababu
DOI:10.1016/s0040-4020(01)81528-3
日期:1990.1
Mercuric acetate catalysed one pot Claisen rearrangement of the cinnamyl alcohol 5, generated the pent-4-enal 9, which on homologation resulted the hex-5-enal 10. Radical cyclisation of the radical anion derived from 10, followed by oxidation provided the ketone mixture 4, a known precursor to the sesquiterpenes (+)-α-cuparenone (1), (+)-epilaurene (3) and laurene (2).