Synthesis of hydrofluorocycloolefins through dehydrofluorination of hydrofluorocycloalkanes in amide solvents

Hydrofluorocycloolefins have outstanding economic and environmental advantages, as well as huge application potentials owing to their zero ozone depletion potentials (ODP) values and low global warming potentials (GWP) values. The synthesis of hydrofluorocycloolefins through dehydrofluorination of hydrohalocycloalkanes in N,N-dimethylformamide (DMF) or N,N-dimethylacetamide (DMAC) was investigated. It was found that the presence of [sbnd]CHF[sbnd] is critical for efficient elimination of HF. The reaction using reagents containing [sbnd]CHF[sbnd] group proceeded very well, whereas elimination was much more difficult to occur for reactants without [sbnd]CHF[sbnd] group. Based on these results, a rational reaction mechanism was proposed.