Highly enantioselective formal aza-Diels–Alder reactions with acylhydrazones and Danishefsky's diene promoted by a silicon Lewis acid
作者:Sharon K. Lee、Uttam K. Tambar、Nicholas R. Perl、James L. Leighton
DOI:10.1016/j.tet.2010.03.036
日期:2010.6
Silicon Lewis acid 3 is effective for the promotion of highly enantioselective cycloaddition reactions of acylhydrazones with Danishefsky's diene (formal aza-Diels–Alder reactions). The reactions are conducted at ambient temperature for 15 min, and produce the products in good yield and with high levels of enantioselectivity. A remarkable solvent-dependent reversal in the sense of absolute stereochemical
硅路易斯酸3可有效促进酰基hydr与Danishefsky的二烯的高度对映选择性环加成反应(正式的aza-Diels-Alder反应)。反应在环境温度下进行15分钟,并以高收率和高对映选择性生产产物。在绝对立体化学诱导的意义上,已经观察到显着的溶剂依赖性逆转。该方法已应用于神经激肽1受体拮抗剂casopitant的高效和立体选择性合成。