Asymmetric reduction of nitroalkenes with baker's yeast
摘要:
Various alpha,beta -disubstituted and trisubstituted nitroalkenes were chemoselectively reduced with baker's yeast to the corresponding nitroalkanes. Stereoselectivities of the reduction of alpha,beta -disubstituted nitroalkenes were modest to low, and e.e.s up to 52% were obtained. Trisubstituted nitroalkenes could be reduced to the corresponding nitroalkanes with excellent enantioselectivities, moderate diastereoselectivities and in good yield. (C) 2001 Elsevier Science Ltd. All rights reserved.
Insights into the diastereoselective control in the sulfa-Michael addition of thiols to nitroalkenes: stereoelectronic effect in the cyclic chelated transition state
two approximately 1,2-diaxial substituents due to stereoelectroniceffectcontrol. The stereoelectroniceffect in the cyclic chelated transition state was probed and verified by tuning the steric bulkiness of the corresponding substituents. The reaction involving 1-nitrocyclohexene provided perfect support for the proposed diastereoselective control model. The current investigation provided not only