8-Endo Cyclization of (Alkoxycarbonyl)methyl Radicals: Radical Ways for Preparation of Eight-Membered-Ring Lactones
作者:Eun Lee、Cheol Hwan Yoon、Tae Hee Lee、Sun Young Kim、Tae Joon Ha、Yong-suk Sung、Sang-Hyun Park、Sangyoub Lee
DOI:10.1021/ja980908d
日期:1998.8.1
Cyclization of (alkoxycarbonyl)methyl radicals generated from bromoacetates proceeds in the 8-endo mode to generate heptanolactones. Three distinct types of 8-endo/5-exo tandem radical cyclizations produce different bicyclic heptanolactones. In certain cases, intramolecularfree-radical attack on the heptanolactone carbonyl group initiates further skeletal rearrangement. Ab initio calculations indicate