Mediating Oxidation States in Decamethyleuropocene Complexes. The Role of the Diazabutadiene Fragment

The Eu diazabutadiene complexes (C5Me5)2Eu(DADBu-t) and (C5Me5)2Eu(DADC6F5) (DADBu-t = t-BuNC(H)C(H)NBu-t; DADC6F5 = C6F5NC(Me)C(Me)NC6F5) have
been prepared, and on the basis of characterization by X-ray
crystallography, magnetic susceptibility, and 1H NMR and IR
spectroscopy, it is concluded that the Eu oxidation states in
these complexes are +2 and +3, respectively. In the case of
(C5Me5)2Eu(DADC6F5), the internal redox process is solvent
sensitive.