Conjugate addition reactions of a (diethoxyphosphinoyl)difluoromethyl anion equivalent to acyclic and cyclic vinyl sulfones
作者:K. Blades、D. Lapôtre、J.M. Percy
DOI:10.1016/s0040-4039(97)01313-0
日期:1997.8
Cerium-mediated conjugate additions of (diethoxyphosphinoyl)difluoromethyllithium to cyclic vinyl sulfones proceeded smoothly; reduction afforded the products of formal alkylation, attaching the difluoromethylene phosphonate group to a secondary carbon atom. With acyclic vinyl sulfones, the addition was considerably less efficient and deprotonation competed with addition. Addition failed completely
铈介导的(二乙氧基膦酰基)二氟甲基锂与环状乙烯基砜的共轭加成反应顺利进行。还原得到正式的烷基化产物,将二氟亚甲基膦酸酯基团连接到仲碳原子上。对于无环乙烯基砜,添加的效率明显较低,并且去质子化与添加竞争。在没有氯化铈(III)的情况下添加完全失败。