Asymmetric synthesis of R-β-amino butanoic acid and S-β-tyrosine: Homochiral lithium amide equivalents for Michael additions to α, β-unsaturated esters.
SG Davies, O Ichihara
文献索引：Davies, Stephen G.; Ichihara, Osamu Tetrahedron: Asymmetry, 1991 , vol. 2, # 3 p. 183 - 186
Abstract Michael addition of the lithium amide derived from RN-(α-methylbenzyl) benzylamine to benzyl E-crotonate is highly stereoselective (95% de) giving after debenzylation and crystallisation homochiral R-β-amino butanoic acid. A similar addition to methyl E-(p-benzyloxy) cinnamate is completely stereoselective giving after debenzylation and acid hydrolysis homochiral S-β-tyrosine as its HCl salt.
![[R-(R*,S*)]-β-[(1-Phenylethyl)(phenylmethyl)amino]-4-(phenylmethoxy)-benzenepropanoic Acid Methyl Ester结构式](https://image.chemsrc.com/caspic/241/134430-95-8.png)