Reaction between aminoalkyl radicals and akyl halides: Dehalogenation by electron transfer?

Aminoalkyl radicals, such as Et2NCHCH3, have low oxidation potentials and are therefore powerful reducing agents. We have found that Et2NCHCH3 reacts with CCl4 and CBr4 in di-tert-butyl peroxide with bimolecular rate constants (measured by LFP) close, or equal, to the diffusion-controlled limit. For the less reactive halide, CH2Br2, the reaction rate is increased substantially by the addition of acetonitrile as a co-solvent. It is tentatively concluded that these reactions occur by electron-transfer from the aminoalkyl to the organohalide with formation of the iminium ion, Et2N+CHCH3 (NMR detection), halide ion and a halomethyl radical, e.g., CCl3 and CHCl2 (ESR, spin-trapping detection).