Synthesis and characterization of heterobimetallic alkoxides of iron(III) with alkali metals and aluminium

Abstract

Bimetallic alkoxides of Fe(III) of the types: M₃Fe(OMe)₆(I) (Ia, M = Li; Ib, M = Na; Ic, M = K); Li₂Fe(OPrⁱ)₅(II); and LiFe(OBu^t)₄(III) have been synthesized by metathetical reactions between FeCl₃ and the appropriate alkali metal alkoxide in the required stoichiometry. Complexes FeAl(OPrⁱ)₆(IVa), FeAl₂(OPrⁱ)(IVb) and Fe₂Al(OPrⁱ)₉(IVc) have also been synthesized by the interaction of Fe(OPrⁱ)₃ and Al(OPrⁱ)₃ in 1:1, 1:2 or 2:1 molar ratios, respectively. Alcoholysis reactions of (IVa) with methanol and t-butanol have been carried out, yielding compounds of compositions FeAl(OMe)₆(Va) and FeAl(OPrⁱ)₂(OBu^t) ₄(Vb), respectively. All these complexes have been characterized by elemental analysis, spectroscopic and magnetic studies. The hydrocarbon soluble complexes IVa, IVb and IVc, and Vb are monomeric by ebullioscopy in benzene.