Real-Time Spectroscopic Analysis Enabling Quantitative and Safe Consumption of Fluoroform during Nucleophilic Trifluoromethylation in Flow

Abstract

The productive use of toxic waste materials derived from industrial processes is one of the main goals of modern chemical research to increase sustainability of the large-scale production. Here we devise a simple and robust strategy for the utilization of trifluoromethane, obtained in large quantities from polytetrafluoroethylene manufacture, and the conversion of this greenhouse gas into valuable fluorinated compounds. The generation of the trifluoromethyl carbanion and its direct and complete consumption through trapping with a number of electrophiles were achieved by a fully contained flow reactor setup. The adoption of modern in-line analytical tools, such as portable Fourier transform infrared and nuclear magnetic resonance devices, allowed the accurate reagent dosing with considerable benefits in terms of controlling the environmental impact during this continuous process. The advantages of the method, with respect to the batch procedure, will be discussed and demonstrated experimentally.