Ammonium bromides/KF catalyzed trifluoromethylation of carbonyl compounds with (trifluoromethyl)trimethylsilane and its application in the enantioselective trifluoromethylation reaction
作者:Satoshi Mizuta、Norio Shibata、Motoki Hibino、Shinichi Nagano、Shuichi Nakamura、Takeshi Toru
DOI:10.1016/j.tet.2007.05.024
日期:2007.8
has been performed by treatment of Me3SiCF3 under initiation by TBAF, TBAT, TMAF as well as CsF. However, these commercially available fluorides are rather expensive and moisture sensitive. Potassium fluoride (KF) is an inexpensive and commonly used fluoride source and can be also used as an initiator for the trifluoromethylation, but the method suffers from the significant limitation that only DMF
醛和酮的三氟甲基化是将CF 3部分引入有机分子的潜在强大方法。通常,通过处理Me 3 SiCF 3进行了三氟甲基化反应。由TBAF,TBAT,TMAF和CsF发起。然而,这些可商购的氟化物相当昂贵并且对湿气敏感。氟化钾(KF)是一种廉价且常用的氟化物源,也可以用作三氟甲基化的引发剂,但该方法存在明显的局限性,即仅DMF可用作溶剂。因此,对于实验室规模以及大规模制备,非常需要新颖的方法。在这里,我们希望报告一种简便的方法,其中KF / TBAB组合物可在多种有机溶剂中用作醛,酮和酰亚胺的三氟甲基化催化剂,从而以高收率或高收率提供三甲基甲硅烷基保护的α-三氟甲基醇。还讨论了该方法在对映选择性三氟甲基化中的应用。