Chiral organometallic NADH mimics: Highly stereoselective reductions of ethyl benzoylformate with a 1,4-dihydronicotinoyl fragment attached to the homochiral auxiliary [(η5-C5H5)Fe(CO)(PPh3)] and possessing a homochiral β-hydroxy-carboxamide at C-5.
作者:Vicky A. Burgess、Stephen G. Davies、Renato T. Skerlj、Mark Whittaker
DOI:10.1016/s0957-4166(00)82187-4
日期:1992.7
complexes were shown to stereoselectively reduce ethyl benzoylformate to either (R)- or (S)-ethyl mandelate by a combination of steric and chelation control. For example, complex (R,R)-12 bearing a carboxamide derived from (R)-(+)-methylbenzylamine afforded (R)-ethyl mandelate in 89% enantiomeric excess. Utilisation of complexes (R,S)-19a and (R,R,S)-22a bearing chiral β-hydroxy-carboxamides derived
装有一组纯手性有机金属NADH模拟物的手性辅助[(η 5 -C 5 H ^ 5)的Fe(CO)(PPH 3)]在C-3羰基和在C-5的手性甲酰胺1,4-已经制备了二氢烟碱酰基片段。这些配合物显示通过空间和螯合控制的组合立体选择性地将苯甲酰基甲酸乙酯还原为(R)-或(S)-扁桃酸乙酯。例如,带有衍生自(R)-(+)-甲基苄基胺的羧酰胺的络合物(R,R)-12提供了89%对映体过量的(R)-扁桃酸乙酯。配合物(R,S)-19a和(R,R,S)-22a的利用 带有分别衍生自缬氨醇和去甲麻黄碱的手性β-羟基羧酰胺的(R)-扁桃酸乙酯的对映体过量大于97%。