Department of Medicinal Chemistry, University of Kansas, Lawrence, KS 66045 (USA), Fax: (+1) 785-864-5326.
Chemistry. 2013 Sep 16;19(38):12800-5. doi: 10.1002/chem.201302328. Epub 2013 Aug 6.
The conversion of an alcohol-based functional group, into a trifluoromethyl analogue is a desirable transformation. However, few methods are capable of converting O-based electrophiles into trifluoromethanes. The copper-mediated trifluoromethylation of benzylic xanthates using Umemoto's reagent as the source of CF3 to form C-CF3 bonds is described. The method is compatible with an array of benzylic xanthates bearing useful functional groups. A preliminary mechanistic investigation suggests that the C-CF3 bond forms by reaction of the substrate with in situ generated CuCF3 and CuOTf. Further evidence suggests that the reaction could proceed via a radical cation intermediate.
将醇基官能团转化为三氟甲基类似物是一种理想的转化。然而，很少有方法能够将 O 型亲电试剂转化为三氟甲烷。本文描述了使用 Umemoto 试剂作为 CF3 源，通过铜介导的苯甲酰基黄原酸酯的三氟甲基化反应来形成 C-CF3 键。该方法与一系列带有有用官能团的苯甲酰基黄原酸酯兼容。初步的机理研究表明，C-CF3 键是通过底物与原位生成的 CuCF3 和 CuOTf 反应形成的。进一步的证据表明，反应可能通过自由基阳离子中间体进行。
