Difluoromethane as a precursor to difluoromethyl borates

Abstract

Difluoromethane (CF₂H₂) is an ecologically-friendly refrigerant which holds promise as a source of CF₂H⁻. However, the weak acidity (pK_a = 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.