Long-Lived Polymer-Supported Dimeric Cinchona Alkaloid Organocatalyst in the Asymmetric α-Amination of 2-Oxindoles
作者:Ravindra P. Jumde、Alessandro Mandoli
DOI:10.1021/acscatal.6b01141
日期:2016.7.1
quantitative yields and high enantiomeric purity (89–95% ee) were attained in the course of 100 reaction cycles of a polystyrene resin-supported Cinchonaalkaloidorganocatalyst in the enantioselective α-amination of 2-oxindoles with diethyl azodicarboxylate. The catalytic material proved stable for >5300 h operation time over 8 months.
Expanding the Scope of Cinchona Alkaloid-Catalyzed Enantioselective α-Aminations of Oxindoles: A Versatile Approach to Optically Active 3-Amino-2-oxindole Derivatives
作者:Tommy Bui、Mar Borregan、Carlos F. Barbas
DOI:10.1021/jo902039a
日期:2009.12.4
A cinchona alkaloid-catalyzed, highly enantioselective, α-amination of oxindoles has been developed. The reaction is general, operationally simple, and affords the desired products in high yields with good to excellent enantioselectivity. Significantly, this study provides a general catalytic method for the construction of a C−N bond at the C3 position of oxindoles as well as for the creation of a