Difluoromethane as a precursor to difluoromethyl borates.

Difluoromethane (CF2H2) is an ecologically-friendly refrigerant which holds promise as a source of CF2H-. However, the weak acidity (pKa = 35-41) and low stability of the conjugate base have prevented its utilization as a chemical feedstock. In this manuscript, we use a Lewis pair approach to deprotonate CF2H2 and capture CF2H- as R3B-CF2H- adducts. One reagent can be used as a base-free Suzuki reagent in palladium-mediated difluoromethylation, where CF2H- transfer is templated by precoordination to an azaborine derived R3B-CF2H- reagent.