The addition of 2-tert-butyldimethylsilyloxyfuran to cyclic N-acyliminium ions containing cyclohexyl-based chiral auxiliaries
作者:Marcelo G.M D'Oca、Ronaldo A Pilli、Ivo Vencato
DOI:10.1016/s0040-4039(00)01749-4
日期:2000.12
addition of silyloxyfuran 5 to chiral five- and six-membered N-acyliminium ions derived from 3/4a,b occurred exclusively through the addition to the N-acyliminium Si face to provide threo-6/7a,b as the major isomer (73–84% yield, 2:1–7:1 diastereoisomeric ratio) which were converted to the corresponding bicyclic lactams 10 and 11 with efficient recovery of the chiral auxiliary.
乙烯基氧化甲硅烷基呋喃5在衍生自3 / 4a,b的手性五元和六元N-酰基离子中的添加仅发生在N-酰基硅Si面上,以提供threo - 6 / 7a,b为主要成分。异构体(73-84%的收率,2:1-7:1的非对映异构体比例)被转化为相应的双环内酰胺10和11,并有效地回收了手性助剂。