A tetranuclear nickel(II) complex, [Ni4(L)4](ClO4)4·C2H3N·2H2O, with an asymmetric Ni4O4 open-cubane-like core

Abstract

A tetranuclear complex with an open-cubane-like core structure was synthesized from 2-methoxy-6-(pyridin-2-yl-hydrazonomethyl)phenol (HL), namely, cyclo-tetrakis(μ-2-methoxy-6-{[2-(pyridin-2-yl)hydrazin-1-ylidene]methyl}phenolato)tetranickel(II) tetrakis(perchlorate) acetonitrile monosolvate dihydrate, [Ni4(C13H12N3O2)4](ClO4)4·C2H3N·2H2O, and characterized using micro-analytical and spectroscopic techniques. The crystal-structure determination reveals the formation of a distorted Ni4O4 cubane-like core architecture encapsulated by four hydrazone Schiff base (HL) molecules. A open-cube tetranuclear architecture is created in which nickel(II) ions of the NiN2O3 unit are connected by μ2-O anions of the phenolate moiety of HL. In this complex, each Ni centre has a slightly distorted square-pyramidal coordination environment. The supramolecular architectures are stabilized via the presence of various intermolecular hydrogen bonds and (aryl–aryl, aryl–chelate and chelate–chelate) stacking interactions.