Mechanistic Analysis and Optimisation of the Defluorination of Hydrofluorocarbon Refrigerants

Herein we report the total-defluorination of 1,1,1,2-tetrafluoroethane (HFC-134a) and pentafluoroethane (HFC-125) using a KOtBu-DMSO mixture to generate KF. The lab production rate and space time yield of KF generated in flow reaches 3.76 gh-1 and 7978 gh-1L-1 from HFC-134a, and 0.57 gh-1 and 57 gh-L-1 from HFC-125. A detailed study of the mechanism of defluorination was conducted through sampling of intermediates via flow aliquots, and analysis by multinuclear NMR spectroscopy.