New, Readily Available Organocatalysts for the Enantioselective Reduction of α-Imino- and β-Imino Esters
作者:Maurizio Benaglia、Martina Bonsignore、Rita Annunziata、Giuseppe Celentano
DOI:10.1055/s-0030-1259941
日期:2011.5
Novel metal-free, readily available chiral catalytic systems for the enantioselective reduction of keto imines are reported. Different β-imino esters were reduced by trichlorosilane in the presence of 10 mol% of a chiral Lewis base easily obtained in one step only from prolinol, in high yields and in up to 85% enantioselectivity; imines bearing an inexpensive and removable chiral auxiliary, were reduced with complete control of the absolute stereochemistry. The methodology was successfully extended to the stereoselective synthesis of α-amino esters.
报道了一种新型无金属、易获得的手性催化系统,用于酮亚胺的对映选择性还原。不同的β-亚氨基酯在三氯硅烷存在下,通过从脯氨醇一次性合成得到的10摩尔%的手性路易斯碱进行还原,获得高产率并达到最高85%的对映选择性;具有经济且可去除的手性辅助基团的亚胺在绝对立体化学的完全控制下被还原。该方法成功拓展至α-氨基酯的立体选择性合成。