Fluorinated radicals were generated from RfSO2Cl by photoredox catalysis under mild conditions, where Rf = n-C4F9, CF3, CF2H, CH2F, CH2CF3, and CF2CO2Me. This method provided a general way to construct fluorinated 2-oxindoles from reaction with N-arylacrylamides via a proposed tandem radical cyclization process.

Fluoroform, CHF3, a non-ozone-depleting, nontoxic, and inexpensive gas can be used as a difluorocarbene source in a process for the conversion of phenols and thiophenols to their difluoromethoxy and difluorothiomethoxy derivatives. The reactions are carried out at moderate temperatures and atmospheric pressure, using potassium hydroxide as base in a two-phase (water/dioxane or water/acetonitrile) process to provide moderate to good yields of the respective products.

A photoredox catalyzed aminodifluoromethylation of unactivated alkenes has been developed in which HCF2SO2Cl is used as the HCF2 radical source. Sulfonamides were active nucleophiles in the final step of a tandem addition/oxidation/cyclization process to form pyrrolidines, and esters were found to cyclize to form lactones. Thus, a variety of pyrrolidines and lactones were obtained in moderate to excellent yield. In order for the cyclization reactions to be efficient, a combination of a copper catalyst (Cu(dap)2Cl) and silver carbonate was crucial to suppressing a competing chloro, difluoroalkylation process.

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Difluoromethyl and carbomethoxydifluoromethyl radicals were generated from their respective sulfonyl chlorides under mild, metal-free conditions leading to efficient atom transfer radical additions (ATRA) to unactivated alkenes to form chloro, difluoromethylated and chloro, carbomethoxydifluoromethylated products.

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