<i>Syn</i>-Selective Synthesis of β-Branched α-Amino Acids by Alkylation of Glycine-Derived Imines with Secondary Sulfonates
作者:Sha Lou、Grace M. McKenna、Steven A. Tymonko、Antonio Ramirez、Tamas Benkovics、David A. Conlon、Francisco González-Bobes
DOI:10.1021/acs.orglett.5b02448
日期:2015.10.16
syn-selective synthesis of β-branched α-amino acids has been developed based on the alkylation of glycine imine esters with secondary sulfonates. The potassium counterion for the enolate, the solvent, and the leaving group on the electrophile were key levers to maximize the diasteroselectivity of the alkylation. The optimized conditions enabled a straightforward preparation of a number of β-branched α-amino
甲顺式的β支链α氨基酸体选择性合成已经基于与二次磺酸盐甘氨酸亚胺酯的烷基化得到了发展。烯醇盐,溶剂和亲电试剂上的离去基团的钾抗衡离子是最大化烷基化非对映选择性的关键手段。优化的条件使得能够直接制备可能具有挑战性的许多β-支链α-氨基酸。