Organic Letters 2010-05-21

Primary amine/(+)-CSA salt-promoted organocatalytic conjugate addition of nitro esters to enones.

Chen Liu, Yixin Lu

Index: Org. Lett. 12(10) , 2278-81, (2010)

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Abstract

The combination of 9-amino-9-deoxy-epi-cinchonine and (+)-CSA resulted in a novel primary amine-based organocatalyst for effective iminium activation of alpha,beta-unsaturated ketones. Such a catalytic system could catalyze the conjugate addition of nitroacetate to enones in a highly enantioselective manner, affording the desired adducts in high yields and with up to 99% ee.