Premium
Diastereo‐ and Enantioselective Michael Addition of 3‐Substituted Oxindoles to Trifluoromethyl‐Substituted Nitro Olefins Catalyzed by a Cinchona ‐Alkaloid‐Derived Squaramide
Author(s) -
Zhao MeiXin,
Ji FeiHu,
Zhao XiaoLi,
Han ZeZheng,
Shi Min
Publication year - 2014
Publication title -
european journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 1434-193X
DOI - 10.1002/ejoc.201301457
Subject(s) - squaramide , stereocenter , chemistry , enantioselective synthesis , cinchona , trifluoromethyl , michael reaction , oxindole , nitro , organocatalysis , adduct , catalysis , stereochemistry , organic chemistry , medicinal chemistry , alkyl
Highly efficient diastereo‐ and enantioselective Michael addition reactions between 3‐substituted oxindoles and trifluoromethylated nitro olefins catalyzed by a quinine‐derived squaramide have been investigated. The corresponding adducts, each bearing a chiral tertiary carbon center attached to a trifluoromethyl group and adjacent to a quaternary stereocenter at the C3 position of the oxindole, were obtained in good to excellent yields (up to 99 %) and with high diastereoselectivities (up to >20:1 dr ) and excellent enantioselectivities (up to 99 % ee ).