A useful conversion of alcohols to alkyl fluorides

A useful conversion of alcohols to alkyl fluorides via their fluoroformates is introduced. The fluoroformates are obtained in nearly quantitative yield from the alcohols by treatment with COF2 (generated in situ from bis(trichloromethyl) carbonate) in ether with KF as an added acid scavenger. The neat fluoroformates are cleaved to the fluorides by heating at 120–125°C using hexabutylguanidinium fluoride (HBGF) as the catalyst.