Highly enantioselective conjugate addition of 1-bromonitroalkanes to α,β-unsaturated ketones catalyzed by 9-amino-9-deoxyepiquinine
作者:Li-ting Dong、Rui-jiong Lu、Quan-sheng Du、Jun-min Zhang、Sheng-ping Liu、Yi-ning Xuan、Ming Yan
DOI:10.1016/j.tet.2009.03.055
日期:2009.5
Asymmetric conjugate addition of 1-bromonitroalkanes to α,β-unsaturatedketones was studied using chiral primary amines as the catalysts. 9-Amino-9-deoxyepiquinine was found to be highly efficient catalyst for the transformation. 4-Bromo-4-nitroketones were obtained with excellent enantioselectivities (97–99% ee) and good yields (61–99%) for a variety of alkyl vinyl ketones. The product could be further