Complexation and photoinduced electron-transfer reaction between perfluoroalkyl iodides and N,N,N′,N′-tetramethylphenylene-1,4-diamine, anilines and piperazines

Abstract

Treatment of tetrafluoro-1,2-diiodoethane 1a or dodecafluoro-1,6-diiodohexane 1b with N,N,N′,N′-tetramethylphenylene-1,4-diamine 2 gave 1 + 1 solid complexes 3a or 3b in high yields. Complex 3a decomposed to give tetrafluoroethylene, iodine and 2 when irradiated with UV or heated. Complex 3b was converted into 6H-dodecafluorohexyl-N,N,N′,N′-tetramethylphenylene-1,4-diamine 4 when irradiated with UV. On treatment of 1a and 1b with piperazine 6a and N,N′-dimethylpiperazine 6b, 1 + 1 solid complexes 7 were similarly obtained. However, heating or irradiating 7 gave no perfluoroalkylated products. Irradiating a mixture of 2 or anilines 13 and perfluoroalkyl iodides 10 in dimethylformamide also gave perfluoroalkylated products. The photoinduced electron transfer reaction involved radical cation 2˙⁺ as a reactive intermediate which was detected by EPR techniques.