Enantioselective Michael Reactions of Chiral Secondary Enaminoesters with 2-Substituted Nitroethylenes. Syntheses of <i>trans,trans</i>-2,4-Disubstituted Pyrrolidine-3-carboxylates
作者:Gilbert Revial、Sethy Lim、Bernard Viossat、Pascale Lemoine、Alain Tomas、Arthur F. Duprat、Michel Pfau
DOI:10.1021/jo000206i
日期:2000.7.1
The Michael reaction of chiral 3-substituted secondary enaminoesters with 2-substituted nitroethylenes leads to (Z)-adducts, with good to excellent diastereoselectivity. The nitro group of these adducts was catalytically reduced to give, after cyclization and chiral amine elimination, pyrrolines or pyrrolidines after further reduction. In particular, the syntheses of ethyl (2R,3S,4S)-2,4-dimethylp
手性3-取代的仲烯氨基酯与2-取代的硝基乙烯的迈克尔反应导致(Z)-加合物,具有良好至优异的非对映选择性。这些加合物的硝基被催化还原,在环化和手性胺消除后,进一步还原后得到吡咯啉或吡咯烷。特别是(2R,3S,4S)-2,4-二甲基吡咯烷-3-羧酸乙酯和(2R,3R,4S)-2-(4-甲氧基苯基)-4-(3,4-(描述了亚甲基二氧基)苯基)吡咯烷-3-羧酸酯。