A One-Pot, Base-Free Annelation Approach to α-Alkylidene-γ-butyrolactones
作者:Russell R. A. Kitson、Richard J. K. Taylor、John L. Wood
DOI:10.1021/ol902191d
日期:2009.11.19
A novel annelation procedure has been developed for the conversion of γ-hydoxy enones into α-alkylidene-γ-butyrolactones. This one-pot method utilizes the Bestmann ylide (triphenylphosphoranylideneketene) and proceeds by way of acylation followed by an intramolecular conjugate addition/proton transfer/Wittig olefination sequence. The procedure is “base-free” and is useful for the preparation of a range
The Preparation of α-Alkylidene-γ-Butyrolactones Using a Telescoped Intramolecular Michael/Olefination (TIMO) Sequence: Synthesis of (+)-Paeonilactone B
作者:Michael G. Edwards、Martin N. Kenworthy、Russell R. A. Kitson、Alexis Perry、Mark S. Scott、Adrian C. Whitwood、Richard J. K. Taylor
DOI:10.1002/ejoc.200800558
日期:2008.10
A novel telescopedintramolecularMichael addition/proton transfer/HWE olefination sequence has been developed to provide rapid access to α-alkylidene-γ-butyrolactones. This methodology has been applied to prepare a range of tetrahydrobenzofuran-2,5-diones, and related systems, and also utilised in an extremely short synthesis of the natural product (+)-paeonilactoneB in enantiomerically pure form