Unusual amino acids IV. Asymmetric synthesis of thienylalanines
作者:Christian Döbler、H.-J. Kreuzfeld、H.W. Krause、M. Michalik
DOI:10.1016/s0957-4166(00)80424-3
日期:1993.8
(Z)-2-N-Acylamino-3-thienyl-acrylic acids and their esters were prepared by known procedures and hydrogenated to the corresponding optically active 2-N-acetyl(or benzoyl)-3-(2- or 3-thienyl)-alanines with optical yields up to 90 % using the rhodium complexes of ''PROPRAPHOS'' 6a,b and O,N-bis(diphenylphosphino)-2-exo-hydroxy,3-endo-methylamino-norbornane 6c as chiral catalysts, Recrystallization and deacylation of the obtained amino acid derivatives yields the optically pure hydrochlorides of the thienylalanines and the free amino acids.