Mild Synthesis of β-Amino-α,α-difluoro Ketones from Acylsilanes and Trifluoromethyltrimethylsilane in a One-Pot Imino Aldol Reaction
作者:Sylvain Jonet、Franck Cherouvrier、Thierry Brigaud、Charles Portella
DOI:10.1002/ejoc.200500106
日期:2005.10
ketones have been very conveniently prepared in a one-pot procedure from acylsilanes, trifluoromethyltrimethylsilane and imines. The key intermediate in this reaction is a difluoroenoxysilane. The Lewis acid promoted imino aldol reaction was performed with BF3·OEt2 or under very mild conditions using a catalytic amount of Yb(OTf)3. The reaction with chiral benzylimines occurred in good yield with 52–78 %
β-氨基-α,α-二氟酮可以通过一锅法由酰基硅烷、三氟甲基三甲基硅烷和亚胺非常方便地制备。该反应的关键中间体是二氟烯氧基硅烷。路易斯酸促进的亚氨基羟醛反应是用 BF3·OEt2 或在非常温和的条件下使用催化量的 Yb(OTf)3 进行的。与手性苄亚胺的反应收率良好,de 为 52-78%。钯催化的氢解得到未保护的 β-氨基-α,α-二氟酮或 β-氨基-α,α-二氟醇。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)