Chlorodifluoromethane or difluoromonochloromethane is a hydrochlorofluorocarbon (HCFC). This colorless gas is better known as HCFC-22, or R-22. It is commonly used as a propellant and refrigerant.

Worldwide production of R-22 in 2008 was about 800 Gg per year, up from about 450 Gg per year in 1998, with most production in developing countries.[2] R-22 use is increasing in developing countries, largely for air conditioning applications. Air conditioning sales are growing 20% annually in India and China. R-22 is prepared from chloroform: HCCl3 + 2 HF ? HCF2Cl + 2 HCl An important application of R-22 is as a precursor to tetrafluoroethylene. This conversion involves pyrolysis to give difluorocarbene, which dimerizes:[4] 2 CHClF2 ? C2F4 + 2 HCl The compound also yields difluorocarbene upon treatment with strong base and is used in the laboratory as a source of this reactive intermediate. The pyrolysis of R-22 in the presence of chlorofluoromethane gives hexafluorobenzene.