Hydrofluoroalkenes have been identified as superior alternatives to existing hydrofluorocarbon refrigerants for automotive applications due to their reduced global warming potential.1 Current synthetic routes to HFAs, however, usually employ chlorocarbons, HF and heterogeneous catalysts at elevated temperatures.2 We present here milder routes to HFAs using Ni complex catalysts with electron-rich ligands (bulky phosphines or N-heterocyclic carbenes) and silanes. Fluoroalkenes typically undergo oxidative coupling with low-valent metal centers to afford metallacyclopentanes.3 In some cases, spontaneous C-F bond cleavage leads to alkenyl nickel fluorides that can react in turn with silanes to generate the fluorosilane and hydrofluoroalkene products along with the zerovalent Ni precursor, thus closing a catalytic cycle. Efficient examples will be presented and and current limitations will be discussed.

Organometallic approaches to low global warming automotive refrigerants: Nickel complex-catalyzed production of C4-hydrofluoroalkenes from C2-fluoroalkenes and silanes

253rd National Meeting (2017)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.