With the aid of quantum chemical calculations (B3LYP/6-31+G(d,p)) we showed that the [3,3]-sigmatropic shift of N-allyl hydrazones occurs with a substantially lower barrier if a single electron transfer precedes rearrangement. Further, the radical cation diazo product was found to decompose to the corresponding homo-allyl radical in quite a facile manner. These results corroborate experimental protocols involving both copper metal and other radical cation progenitors (see Thomson et al. DOI:10.1021/ja7101967).
Siebert, M.R. and Tantillo, D.J. Organic Letters, 2008, 10, 3219-3222. “[3,3]-Sigmatropic Shifts of N-Allylhydrazones: Quantum Chemical Comparisons of Concerted and Radical Cation Pathways.” 10.1021/ol801107j.