α-Difluoromethylation on sp3 Carbon of Nitriles Using Fluoroform and Ruppert-Prakash Reagent

Difluoromethylation on sp(3) carbon of various nitrile compounds with lithium base and fluoroform (CF3H), which is an ideal difluoromethylating reagent, is shown to provide the alpha-difluoromethylated nitrile products with an all-carbon quaternary center in moderate to high yields. The Ruppert-Prakash reagent (CF3TMS) is also applicable to the reaction, affording the alpha-siladifluoromethylated nitrile products, which can be utilized for sequential carbon carbon bond-forming reactions. These reactions using 1.1 equiv of lithium base, 1.5-2.0 equiv of CF3H or CF3TMS, and easily accessible nitrile derivatives are completed in only a few minutes, resulting in the formation of valuable difluoromethylated compounds.