Transition-metal-free synthesis of CMe2CF3-containing chroman-4-ones via decarboxylative trifluoroalkylation

(NH4)2S2O8-mediated decarboxylative trifluoroalkylation of alkenes with 3,3,3-trifluoro-2,2-dimethylpropanoic acid under metal-free conditions has been described. This approach provides a new pathway to directly synthesize a series of CMe2CF3-containing chroman-4-ones from simple chemical feedstocks. Particularly, the utility of the method was demonstrated by its application in the synthesis of CMe2CF3-derived TRPV1 precursors.