The reaction of 2•TMEDA (TMEDA = tetramethylethylenediamine) with HCF3 also selectively generated fluoroalkene products, in this case a 3:1 mixture of Z:E PhCH=CF(SiMe3) (Z:E-4) formed in 72 % NMR yield (Figure ). The major and minor stereoisomers were characterised by diagnostic resonances in the F NMR spectrum at d = -106.1 ppm (d, JH-F = 35.6 Hz) and -113.5 ppm (d, JH-F = 52.2 Hz) respectively. The assignment of the connectivity and stereochemistry of the products was achieved through a combination of J values and computational prediction of F NMR chemical shift values (see supporting information for details). Ultimately, unambiguous assignment was achieved through a stereospecific proteodesilylation of the reaction mixture to generate a 3:1 mixture of E:Z PhCH=CFH and comparison against literature (Figure ). When the reaction was scaled-up (0.01 to 4 mmol), a 3.8:1 mixture of Z:E-4 was formed in only 44% yield (36 % isolated), likely due to issues with biphasic mixing on larger scales. Both the yield and gas destruction efficiency of the reaction could, however, be improved by operating in flow. Application of the optimum process conditions to the defluoroalkylation reaction of 2•TMEDA with HCF3 yielded a combined 67% (51% isolated) of a 3:1 mixture of Z:E-4 with just 2.8 equiv. of gas, at a production rate of 4.8 mmol h -1 (Figure ).