Asymmetric Induction at C(?) and C(?) ofN-Enoylsultams by Organomagnesium 1,4-Addition/Enolate Trapping
作者:Wolfgang Oppolzer、Giovanni Poli、Arend J. Kingma、Christian Starkemann、G�rald Bernardinelli
DOI:10.1002/hlca.19870700825
日期:1987.12.16
The 1,4-addition of alkylmagnesium chlorides to conjugated N-enoylsultams and subsequent ‘enolate trapping’ with aq. NH4Cl or MeI/hexamethylphosphoric triamide generated centers of asymmetry at C(β) and/or at C(α) with good to excellent π-face defferentiation as demonstrated by the conversions 12, 14, and 89. This holds also for the regioselective 1,4-addition of EtMgC1 to a dienoylsultam (1516). Reactive
烷基镁氯化物在1,4-加成反应中与共轭N-烯酰基阿磺酰胺结合,随后用碳酸氢钠水溶液进行“烯醇式捕集”。NH 4 Cl或将MeI /六甲基磷酰胺中C(β)和/或在C(α)具有良好的作为表明由转化优良π共面defferentiation产生不对称中心1 2,1 4,和8 9。这也适用于将EtMgC1在区域选择性地1,4-加成至二烯丙基舒马坦(15 16)。反应构象1 ≠,8 ≠,13和14假定X射线证据与X射线证据一致,X射线证据也用于确定产物9j的结构。