Asymmetric Nitroaldol Reactions of Nitroalkanes with Isatins Catalyzed by Bifunctional Cinchona Alkaloid Derivatives

作者:Li, Mei-Qiu; Zhang, Jin-Xin; Huang, Xiao-Fei; Wu, Bin; Liu, Zhao-Min; Chen, Jian; Li, Xiang-Dong; Wang, Xing-Wang*
来源:European Journal of Organic Chemistry, 2011, 2011(27): 5237-5241.
DOI:10.1002/ejoc.201100824

摘要

The enantioselective nitroaldol reactions of isatins with nitroalkanes were smoothly carried out by organocatalysis. A C6'-OH cinchona alkaloid derivative bearing a C9-OBn group exhibited outstanding catalytic efficiency as an acid-base bifunctional catalyst for the nitroaldol reaction of isatins with nitromethane, providing 3-hydroxy-3-(nitromethyl)indolin-2ones in good yields (90-98%) and with good to high enantiomeric excess values (72-95%). The resultant oxindole derivatives are highly important for the synthesis of related natural products and pharmaceutically active compounds.