A New Class of Urea-Substituted Cinchona Alkaloids Promote Highly Enantioselective Nitroaldol reactions of Trifluoromethylketones

作者：Palacio Carole; Connon Stephen J^*

来源：Organic Letters, 2011, 13(6): 1298-1301.

DOI：10.1021/ol103089j

The first class of bifunctional cinchona-alkaloid catalysts incorporating a urea moiety at C-5' has been developed. These materials catalyze the efficient and highly enantioselective 1,2-addition of nitromethane to trifluoromethylketones to form synthetically pliable products incorporating a quaternary stereocenter. Excellent product yields and levels of enantiomeric excess are possible, and the optimum catalyst structure is capable of promoting the Henry reaction involving alkyl trifluoromethylketones with unprecedented enantioselectivity.

• 出版日期2011-3-18