Enantioselective additions of (trifluoromethyl)trimethylsilane to α-imino ketones derived from aryl glyoxals
作者:Emilia Obijalska、Grzegorz Mlostoń、Alice Six
DOI:10.1016/j.tetlet.2013.02.093
日期:2013.5
Chemoselective additions of (trifluoromethyl)trimethylsilane to α-imino ketones derivedfrom aryl glyoxals in the presence of a catalytic amount of enantiomerically pure ammonium bromides, derivedfrom Cinchona alkaloids and K2CO3 led to O-silylated β-imino alcohols. Subsequent reduction of these products with NaBH4 gave β-(N-alkyl)amino-α-trifluoromethyl alcohols for which the ee values were 30–71%
在催化量的对映体纯的溴化铵,金鸡纳生物碱和K 2 CO 3的存在下,将(三氟甲基)三甲基硅烷化学选择性加成到芳基乙二醛的α-亚氨基酮上,生成O-甲硅烷基化的β-亚氨基醇。随后用NaBH 4还原这些产物,得到β-(N-烷基)氨基-α-三氟甲基醇,在最佳条件下,其ee值为30 – 71%。根据在手性溶剂化剂存在下记录的1 H或19 F NMR光谱确定最终产物的对映体过量。