Bis(1,4-di-tert-butyl-1,4-diazabutadiene)gallium is not a gallium(II) compound

Abstract

The recently reported paramagnetic compounds (dbdab)₂M (dbdab = 1,4-di-tert-butyl-1,4-diazabutadiene, M = Ga, Al), both contain trivalent metal bound to one singly and one doubly reduced dbdab ligand; the larger metal hyperfine coupling in the EPR spectrum of the gallium complex is not due to a gallium(II) oxidation state, it is simply a result Of the quite large isotropic hyperfine coupling constants of ⁶⁹Ga and ⁷¹Ga as demonstrated previously for the related radicals (bpy^–˙)M^IIIMe₂(bpy = 2,2′-bipyridine).