Regioselective 1,4-Silylcupration of 1,3-Dienes − Characterization and Electrophilic Trapping of the Intermediate (σ-Allyl)copper Complex
作者:Vilnis Liepins、Jan-E. Bäckvall
DOI:10.1002/1099-0690(200211)2002:21<3527::aid-ejoc3527>3.0.co;2-h
日期:2002.11
Silylcupration reactions of 1,3-dienes with a cyanocuprate reagent PhMe2SiCuCNLi produce a (4-silyl-2-alken-1-yl)copper complex, which was trapped by electrophiles. The use of allylic phosphates as electrophiles resulted in highly regioselective reactions with overall 1,4-addition of the silyl and allyl moieties across the diene. Water (H3O+) or acetyl chloride as the electrophile afforded a mixture
1,3-二烯与氰铜酸盐试剂 PhMe2SiCuCNLi 的甲硅烷基铜化反应产生 (4-silyl-2-alken-1-yl) 铜络合物,该络合物被亲电子试剂捕获。使用烯丙基磷酸酯作为亲电试剂导致高度区域选择性反应,整个二烯中甲硅烷基和烯丙基部分的整体 1,4-加成。水 (H3O+) 或乙酰氯作为亲电试剂提供 1,2- 和 1,4- 加成产物的混合物,而二氧化碳则产生高度区域选择性的 1,2- 加成。中间体(4-甲硅烷基-2-链烯-1-基)铜配合物通过核磁共振光谱表征。讨论了 1,3-二烯的甲硅烷基铜化反应和随后的亲电捕获机制。(© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)