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.
Department of Chemistry & Medicinal Chemistry Program, Life Sciences Institute, National University of Singapore, 3 Science Drive 3, Republic of Singapore, 117543.
