Organocerium additions to proline-derived hydrazones: synthesis of enantiomerically enriched amines
作者:Scott E. Denmark、James P. Edwards、Theodor Weber、David W. Piotrowski
DOI:10.1016/j.tetasy.2010.04.042
日期:2010.5
The addition of organocerium reagents (from both organolithium and organomagnesium precursors) to chiral aldehyde hydrazones prepared from 1-aminoproline derivatives has been studied. The additions proceed in good yield and high diastereoselectivity and with good nucleophile (Me, n-Bu, i-Pr, t-Bu, Ph, etc.) and substrate scope (alkyl, alkenyl and aryl). The resulting hydrazines can be converted to
Palladium-catalyzedasymmetricallylicalkylation of 1,3-diphenyl-2-propenyl acetate 18 with a dimethyl malonate–BSA–LiOAc system has been successfully carried out in the presence of new chiral aminophosphine ligands 1–5 in good yields with good enantioselectivities (up to 85% e.e.).