Dithiane Additions to Vinyl Epoxides: Steric Control over the S<sub>N</sub>2 and S<sub>N</sub>2‘ Manifolds
作者:Amos B. Smith、Suresh M. Pitram、Matthew J. Gaunt、Sergey A. Kozmin
DOI:10.1021/ja0283100
日期:2002.12.1
High chemoselectivity can be achieved in the addition of lithium dithiane anions to vinyl epoxides exploiting the steric nature of the dithiane substituent. Unencumbered dithiane anions afford SN2 adducts, whereas sterically encumbered anions lead primarily to SN2' adducts. Furthermore, the SN2' addition occurs syn to the vinyl epoxide.