Enantioselective Organocatalytic Michael Addition of Malonates to α,β-Unsaturated Ketones
作者:Pengfei Li、Shigang Wen、Feng Yu、Qiaoxia Liu、Wenjun Li、Yongcan Wang、Xinmiao Liang、Jinxing Ye
DOI:10.1021/ol802892h
日期:2009.2.5
derived from 1,2-diaminocyclohexane and 9-amino (9-deoxy) cinchona alkaloid was developed into asymmetricMichaeladdition 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.
A General Organocatalytic Enantioselective Malonate Addition to α,β-Unsaturated Enones
作者:Veit Wascholowski、Kristian Rahbek Knudsen、Claire E. T. Mitchell、Steven V. Ley
DOI:10.1002/chem.200800673
日期:2008.7.7
A general enantioselective organocatalytic conjugate addition procedure of a variety of malonates to alpha,beta-unsaturated enone systems is presented. The reaction is efficiently catalysed by the pyrrolidinyl tetrazole catalyst 1. Cyclic, acyclic and aromatic enones can be used and the reaction with ethyl malonates 3 b provides the Michaeladdition products in high yields with good to excellent enantioselectivities