Enantioselective Organocatalytic Michael Addition of Malonates to alpha,beta-Unsaturated Ketones

摘要

A novel type of primary amine thiourea organocatalysts derived from 1,2-diaminocyclohexane and 9-amino (9-deoxy) cinchona alkaloid was developed into asymmetric Michael addition of malonates to enones. A series of cyclic and acyclic enones could react very well with different malonates in the presence of 4 with 0.5-10 mol % catalyst loading affording chiral Michael adducts with excellent yields and ee values.