Towards a universal organocatalyst for the synthesis of enantioenriched phenylalanine derivatives by enantioselective decarboxylative protonation
作者:Morgane Pigeaux、Romain Laporte、David C. Harrowven、Jérôme Baudoux、Jacques Rouden
DOI:10.1016/j.tetlet.2016.09.001
日期:2016.10
Access to enantioenriched non-proteogenic phenylalanine derivatives is described using the enantioselective decarboxylative protonation reaction of amidohemimalonate esters catalysed by various cinchona-based compounds. This study compares the catalytic efficiency as well as the enantioselectivity induced by three types of common organocatalysts, namely thioureas, squaramides and bis-cinchona squaramides
使用由各种基于金鸡纳的化合物催化的酰氨基半乳糖酸酯的对映选择性脱羧质子化反应,描述了获得对映体富集的非蛋白原性苯丙氨酸衍生物。这项研究比较了三种常见的有机催化剂(硫脲,方酸酰胺和双金鸡纳方酸酰胺)引起的催化效率以及对映选择性。这项工作的主要成果之一是观察到半棉酸盐的N-保护基团对其与催化剂相互作用的重大影响。在温和条件下进行的该方法具有良好的底物范围和官能团耐受性。在某些情况下,还可以使用亚化学计量的催化剂,同时提供良好的产率和选择性。