Effective construction of quaternary stereocenters by highly enantioselective α-amination of branched aldehydes
作者:Ji-Ya Fu、Xiao-Ying Xu、Yan-Chun Li、Qing-Chun Huang、Li-Xin Wang
DOI:10.1039/c0ob00406e
日期:——
A highly efficient enantioselectiveα-amination of branchedaldehydes with azadicarboxylates promoted by chiral proline-derived amide thiourea bifunctional catalysts was developed for the first time, affording the adducts bearing quaternary stereogenic centers with excellent yields (up to 99%) and enantioselectivities (up to 97% ee).
Isothiouronium salt based chiral proline amide as efficient bifunctional organocatalyst for direct asymmetric aldol reactions in aqueous medium
作者:Hyoung Min Yeo、Sungmin Kang、Taek Hyeon Kim
DOI:10.1016/j.tetlet.2021.153324
日期:2021.9
We developed the first chiral proline amide-isothiouronium based bifunctional organocatalyst, it was prepared by methylation of the corresponding thiourea. This asymmetric catalyst provides aldol products in high to quantitative yields while achieving excellent control performance of diastereoselectivities (anti/syn, up to 95:5 dr) and enantioselectivity (up to 99% ee) in the aldol reaction of various
A series of secondaryamine-thioureacatalysts 1a-1d derived from L-proline and chiral diamine were prepared and successfully applied to the Michael addition of acetone to trans-nitroalkenes in excellent yields (up to 99%) and enantioselectivities (44-91% ee).