Mn(OAc)-Mediated Addition Reactions of NaSOCF and Perhalogenated Carboxylic Acids with Unactivated Alkenes Conjectured by a Single Electron Transfer and Halogen Abstraction Mechanism.

A free-radical halotrifluoromethylation of olefins by using Mn(OAc)·2HO, CFSONa, and perhalogenated carboxylic acids has been achieved. Perhalogenated carboxylic acids act as a halogen source and CFSONa acts as a CF source. The reaction displayed good tolerance of functional groups in the substrates under mild conditions. The radical clock experiment and TEMPO inhibition experiment support a radical process. The halogen reagent competition experiment shows that the last step of halogenation process is mainly through a halogen abstraction mechanism.