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An AgI-mediated ethoxycarbonyldifluoromethylation of isocyanides has been developed. This radical cascade reaction involves the addition of difluoromethylene radical to the isocyanide functionality, and subsequent homolytic aromatic substitution to give difluoromethylated phenanthridines with a good functional-group tolerance.

The first AgI-mediated C–H ethoxycarbonyl difluoromethylation with TMSCF2COOEt (TMS = trimethylsilyl) has been developed. The radical difluoromethylation proceeds smoothly to give the difluoromethylated arenes in moderate to high yields with Friedel–Crafts-type regioselectivity. Mechanistic studies indicate that the innate C–H difluoromethylation proceeds through an electrophilic radical-type pathway.

A simple AgI-mediated direct difluoromethylation reaction of activated alkenes by using TMSCF2COOEt (TMS = trimethylsilyl) under mild reaction conditions has been described. This reaction tolerates a variety of functional groups and allows for a highly efficient synthesis of various difluoro-containing oxindoles. Mechanistic investigations indicate that a difluoromethyl radical initiated the cascade sequence by undergoing an addition reaction to the alkene.

In this new Ag(I)-promoted reaction between N-arylacrylamides and ethyl trimethylsilyldifluoroacetate, the corresponding 3-(2-ethoxycarbonyl-2,2-difluoroethyl)-2-oxo-2,3-dihydro-1H-indoles have been prepared in good yields.

A mild, versatile and efficient method for the silver(I)-catalyzed oxidative decarboxylative gem-difluoromethylenation has been developed. The radical cascade reaction comprises the addition of an oxidatively generated difluoromethylene radical to the isonitrile functionality and subsequent homolytic aromatic substitution. It provides a novel and efficient access to the C-CF2 bond formation.

Efficient direct gem-difluoromethylenation of an sp3-hybridized carbon center in benzyl bromides using benzo-1,3-azolic (oxa-, thia- or aza-) difluoromethyl bromides for construction of a CH2–CF2 linkage has been developed through radical/radical C–C cross-coupling via two separate single electron transfer processes (SET) under the promotion of different copper sources.