Generation of 2-azapentadienyl anions and their cycloaddition with alkenes. Synthesis of 2-alkenylpyrrolidines
作者:William H. Pearson、Valerie A. Jacobs
DOI:10.1016/0040-4039(94)88209-6
日期:1994.9
α,β-Unsaturated imines 2 bearing an N-[1-(tri-n-butylstannyl)]alkyl group were transmetalated with n-BuLi to generate 2-azapentadienyl anions 3 which underwent [4πs+2πs] anionic cycloadditions with alkenes to afford 2-alkenylpyrrolidines 4 after workup with an electrophile. The alkenyl group could be oxidized to a diol, aldehyde, or ester. The imine 2 was found to undergo a [1,5]-sigmatropic rearrangement
α,β不饱和亚胺2轴承的Ñ - [1-(三- Ñ -butylstannyl)]烷基用transmetalated Ñ正丁基锂,以生成2- azapentadienyl阴离子3其中后行[4πS+2πs]与烯烃的阴离子环加成,得到用亲电子试剂处理后的2-烯基吡咯烷4。烯基可被氧化为二醇,醛或酯。亚胺2被发现经历三的[1,5] -sigmatropic重排Ñ在80℃下-butylstannyl组来提供2- azabutadiene 5。