新型Rh_2(esp)_2配体手性类似物的合成

以(R)-叔丁基亚磺酰胺为手性助剂,与1,3-苯二甲醛经缩合反应制得关键中间体——(Rs,Rs)-双叔丁基亚磺酰亚胺(7);锂化的羧酸酯与7经不对称加成反应合成了两个新型的Rh_2(esp)_2配体类似物——(Rs,Rs',R,R')-β-胺基羧酸酯和(Rs,Rs',R,R',R,R')-α,β-氮杂环丙烷羧酸酯,产率分别为96%和65%,非对映选择性均大于20∶1。化合物的结构经1H NMR和13C NMR表征。

Synthesis of Novel Enantioenriched Analogues of Rh2 (esp) 2 Ligand

A synthetic approach toward the enantioenriched analogues of α,α,α′,α′-tetramethyl-1 ,3-benzenedipropionic acid which was the ligand of Rh2 ( esp) 2 catalyst was reported.In this process, the chiral (R)-tert-butanesulfinyl diimine derived from 1,3-benzenedialdehyde was used in the nucleophil-ic additions of lithium ester enolates to give two novel chiral analogues of the “esp” esters that are (Rs,Rs′,R,R′)-β-amino esters and (Rs,Rs′,R,R′,R,R′)-α,β-aziridinyl esters in yields of 96%and 65% with excellent diastereoselectivity ( dr >20 ∶1 ).The structures were characterized by 1 H NMR and 13 C NMR.