Synthesis and electron-transfer reactions of some 3-difluoroacetylated imidazo[1,2-a]pyridine derivatives

The synthesis of new 3-chlorodifluoroacetylated imidazo[1,2-a]pyridines 1–6 and their difluoroacetyl derivatives is presented. The reductive cleavage of the halogenated ketones was investigated by cyclic voltammetry, and tetrakis(dimethylamino)ethylene (TDAE) was found to be an effective reductant for the generation of the corresponding α,α-difluoroacetyl anions and for the synthesis of new gem-difluoromethylated imidazo[1,2-a]pyridine derivatives 7–12.