Tandem radical cyclization of acyclic homoallylic xanthates: cyclopentannulated .gamma.-thionolactone and .gamma.-lactones
作者:Seiji Iwasa、Makoto Yamamoto、Shigeo Kohmoto、Kazutoshi Yamada
DOI:10.1021/jo00008a048
日期:1991.4
The first tandem radical cyclization of linear homoallylic xanthates was explored. Homoallylic xanthates prepared from alpha,beta-unsaturated esters were easily cyclized by tin hydride with an radical initiator to give the corresponding thionolactone annulated cyclopentane skeleton in a high yield. The stereochemistry of cyclized products was also discussed. Thionolactones obtained were oxidized chemoselectivity with m-CPBA under neutral condition to afford gamma-lactones in a high yield.