Asymmetric Synthesis of α-Alkylated <i>N</i>-Sulfinyl Imidates as New Chiral Building Blocks
作者:Filip Colpaert、Sven Mangelinckx、Guido Verniest、Norbert De Kimpe
DOI:10.1021/jo900046t
日期:2009.5.15
outstanding yields. These imidate hydrochlorides proved to be excellent intermediates for an easy transformation to chiral amides in good yields and enantiomeric excess upon simple heating in chloroform. Hydrolysis of the α-benzylated imidate hydrochlorides afforded the corresponding chiral esters with >95% ee.
通过叔丁烷亚磺酰胺与原酸酯的缩合反应制得的N-亚磺酰亚胺基的α-烷基化反应可生成非对映异构体比率优良的α-取代的N-亚磺酰亚胺基(dr高达> 99:1),收率很高。烷基化的N-亚硫酰亚胺基的去保护基使得能够以优异的产率得到相应的亚氨酸盐酸盐。这些亚氨酸盐酸盐被证明是极好的中间体,易于在氯仿中简单加热,容易以高收率转化成手性酰胺,而对映体过量。水解α-苄基亚氨酸盐酸盐,得到相应的手性酯,其ee> 95%。