Synthesis of highly enantiomerically enriched amines by the diastereoselective addition of triorganozincates to N-(tert-butanesulfinyl)imines
作者:Raquel Almansa、David Guijarro、Miguel Yus
DOI:10.1016/j.tetasy.2008.10.012
日期:2008.11
different from the ones observed with the corresponding Grignard reagents, which allows, in several cases, the preparation of both enantiomers of an amine from the same imine substrate. When mixed triorganozincates are used, one can take advantage of the slow transfer rate of the methyl group to use it as a non-transferable one. Both aromatic and aliphatic aldimines, as well as activated ketimines, are good
三有机锌酸酯与(R)-N-(叔丁烷亚磺酰基)亚胺的反应以良好或优异的产率得到了预期的α-支化的亚磺酰胺,非对映体比率高达98:2。该ñ产物的-亚磺酰基可通过酸处理容易地除去,从而以高达96%的对映体过量提供相应的手性伯胺。由三有机锌酸盐显示的反应性和选择性不同于用相应的格氏试剂观察到的反应性和选择性,这在某些情况下允许从相同的亚胺底物制备胺的两种对映异构体。当使用混合的三有机锌酸酯时,可以利用甲基的缓慢转移速率将其用作不可转移的甲基。芳族和脂族亚胺以及活化的酮亚胺都是这些加成反应的良好底物。