A Heterotetranuclear Zinc(II)-Cerium(IV) Salamo Complex Possessing Deca- and Dodeca-Coordinated Cerium(IV) Atoms: Synthesis, Structure, and Photophysical Properties

Abstract

A heterotetranuclear zinc(II)-cerium(IV) complex [(ZnL)₂Ce(OAc)₂][Ce(NO₃)₆] · Py (H₂L = 6,6′-methoxy-2,2′-[1,2-ethylenedioxybis(nitrilomethylidyne)]diphenol and Py = pyridine) is successfully prepared by a one-pot reaction of a Salamo-type ligand H₂L with Zn(OAc)₂·2H₂O, Ce(NO₃)₃-6H₂O, and an auxiliary ligand Py. The Znⁿ-Ce^IV complex consists of one dicationic [(ZnL)₂Ce(OAc)₂]²⁺ unit with a deca-coordinated Ce^IV atom, one [Ce(NO₃)6]²⁻ dianionic unit with a dodeca-coordinated Ce^IV atom, and one uncoordinated Py molecule. Interestingly, the two Ce^IV atoms are positive tetravalent, which may probably be due to the oxidation of trivalent Ce^m atoms during the reaction. Moreover, the photophysical properties of the Znⁿ-Ce^IV complex are studied.