Palladium‐Catalyzed Direct Approach to α‐Trifluoromethyl Alcohols by Selective Hydroxylfluorination of gem‐Difluoroalkenes.

A novel palladium‐catalyzed selective hydroxylfluorination of gem‐difluoroalkenes has been developed. By employing easily obtainable gem‐difluoroalkenes and NFSI as the fluorine source, the scope, advantages, and limitations of this reaction were investigated. The reaction presents an efficient synthesis to afford a series of α‐trifluoromethyl alcohols in good to excellent yields. Furthermore, this reaction probably proceeds via oxidation of Pd0 to PdII fluoride complex by NFSI, followed by fluoropalladation of gem‐difluoroalkenes to generate an α‐trifluoromethylbenzyl–Pd intermediate. And this strategy offers more possibilities for the construction of other bonds, such as C–C, C–N and C–S. [ABSTRACT FROM AUTHOR]