A process for hydrogenating one or more functional groups in a compound, for example an alkene, involves contacting the compound with a hydrogen source in the presence of a reaction solvent and suitably in the presence of a catalyst, such as Wilkinson's catalyst. The reaction solvent may be a C 1 - 4 fluorinated hydrocarbon or a C 1 - 4 hydrofluorocarbon ether, with difluoromethane, tetrafluoroethane and heptafluoropropane being preferred solvents.