in batch is impractical due to the large volumes of gases involved, and potential for extreme exotherms. Continuous flow methods offer a key enabling technology to solve these problems. Flow methods allow safe scale-up and process optimization, through efficient liquid-gas mixing, increased heat dissipation, and reduction of reactor volumes. One of the first continuous flow processes that used HFCs was reported by Grushin and coworkers in 2014. They demonstrated that 'ligandless' [CuCF3] could be prepared from HCF3, CuCl, KOtBu in DMF using Et3N•3HF as a stabilising agent to slow degradation. [CuCF3] itself is a versatile trifluoromethylating agent that has been applied in a series of carbon-carbon bond forming reactions. Since this breakthrough, HCF3 has been used as trifluoromethylating agent under flow conditions in base-mediated (e.g. KOtBu, KHMDS) reactions with aldehydes and ketones, imines, and esters. Kappe and coworkers have reported the difluoromethylation of enolisable esters with HCF3 in the presence of a base. This methodology has been applied to a scalable continuous flow process for the synthesis of Eflornithine with production rates of 24 mmol h -1 . A similar approach has been used for the difluoromethylation of enolisable nitriles, albeit with the design of a specialist reactor to control the temperature in flow. To the best of our knowledge, continuous flow methods have yet to be applied to synthetic transformations of HFOs.