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A new class of urea-substituted cinchona alkaloids promote highly enantioselective nitroaldol reactions of trifluoromethylketones.

Carole Palacio and Stephen J Connon

Org Lett 13(6):1298-301 (2011) PMID 21338077

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.

DOI: 10.1021/ol103089j
Version: za2963e q8za3 q8zb6 q8zcb q8zdf q8ze0 q8zf0 q8zg3
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