Continuous Process for Production of CuCF3 via Direct Cupration of Fluoroform

The first continuous flow process has been developed for the synthesis of a superior trifluoromethylating reagent, “ligandless” CuCF₃, from fluoroform, by far the best CF₃ source in terms of availability, cost, and atom economy. Optimization of the residence time and feed rates for CHF₃ (gas), the cuprating reagent (premade from CuCl and t-BuOK in a 1:2 ratio) in DMF, and the stabilizer (Et₃N·3HF) at 23 °C and atmospheric pressure has allowed for the continuous production of CuCF₃ in consistently high yields of up to 94%. The thus produced CuCF₃ has been shown to be as highly efficient a trifluoromethylating agent as the one from the previously developed batch process.