Organoaluminum Radical Complexes from the Single Electron Transfer Reaction of Diisobutylaluminum Hydride with N-Heterocycles

The single electron transfer (SET) reactivity of metal alkyls and hydrides is currently receiving growing attention [1-3]. Thus, it has been demonstrated that aluminum species AIX3 (X = R [4], H [5], Cl [6]) can react with reducible carbonyl compounds to form aluminium containing radical complexes [4-6]. Besides carbonyl compounds, certain N-heterocycles can also be used as electron transfer substrates [2, 3, 7]; however, molecules such as pyrazine (1), 2,2'-bipyridine (2), and 4,4'bipyridine (3) do not form radical complexes with trimethylaluminum unless an alkali metal is used for reduction [8, 9].