Highly Enantioselective Conjugate Additions of Phosphites to α,β-Unsaturated<i>N</i>-Acylpyrroles and Imines: A Practical Approach to Enantiomerically Enriched Amino Phosphonates
作者:Depeng Zhao、Yuan Wang、Lijuan Mao、Rui Wang
DOI:10.1002/chem.200901901
日期:2009.10.19
The first highly enantioselective phosphonylation of α,β‐unsaturated N‐acylpyrroles has been developed. Excellent yields (91–99 %) and enantioselectivities (up to >99 % enantiomeric excess (ee)) were observed for a broad spectrum of both phosphites and N‐acylpyrroles under mild conditions. In particular, when diethyl phosphite was employed to test the scope of the N‐acylpyrroles, almost optically pure
已经开发出第一个高度对映体选择性的α,β-不饱和N-酰基吡咯烷酰基的膦酰基化反应。在温和的条件下,对于亚磷酸酯和N-酰基吡咯,在宽广的亚磷酸酯和N-酰基吡咯中均观察到优异的收率(91–99%)和对映体选择性(高达> 99%对映体过量(ee))。特别是,当使用亚磷酸二乙酯测试N-酰基吡咯的范围时,对于20个N-酰基吡咯的实例,几乎获得了光学纯的产品(98至> 99% ee)。此外,可以通过几次简单的吡咯基膦酸酯转化获得光学纯的α-取代的β-或γ-氨基膦酸酯。N的多功能性酰基吡咯部分使磷加合物成为强大的手性结构单元,可合成各种含膦酸酯的化合物。最后,本策略也可用于对映选择性高(93到> 99%ee)的N-嘧啶的不对称氢膦酰化反应 。