New heterometallic copper zinc alkoxides: synthesis, structure properties and pyrolysis to Cu/ZnO composites

Abstract

The copper compound [(THF)KCu(O t Bu) 3] ∞ 1 was obtained by interaction of a 1:1 mixture of ZnCl 2/CuCl 2 with KO t Bu. Bi- and trifunctional aminoalcohols were used to synthesize the intramolecularly donor stabilized Cu(II) alkoxides Cu(OCH(R)CH 2NMe 2) 2 ( 3: R=Me, 4: =CH 2NMe 2) where 4 was structurally characterized. Lewis acid–base adduct formation with (Me 3Si) 3CZnCl gave the heterodinuclear compounds (Me 3Si) 3CZnCl · Cu(OCH(R)CH 2NMe 2) 2 ( 5: R=Me, 6: R=CH 2NMe 2), which were characterized by X-ray single-crystal structure analysis. The two metal centers Cu and Zn of 5 and 6 are bridged by two oxygen atoms to form a Cu–O–Zn core. Pyrolysis of compounds 5 and 6 in dry argon or a H 2/N 2 mixture at atmospheric pressure forms metallic copper and zinc oxide, whereas pyrolysis under O 2/Ar forms additionally oxidized copper species. Elemental analysis of the pyrolysis products showed carbon and nitrogen contamination. Scanning electron microscopy and energy dispersive X-ray analysis were performed to get information on the morphology and the chemical composition of the pyrolysis products.