Syntheses, structures and properties of µ₃-carbonato bridged trinuclear zinc(II) complexes containing a tailored tetradentate amine

Abstract

Two trinuclear zinc(II) compounds of the type [Zn₃(µ₃-CO₃)(L)3](X)4 [L = N,N′-bis(3-aminopropyl)-1,2-ethanediamine; X = ClO₄ (1), PF₆ (2)] have been prepared by reactions of 1:1 molar ratio of zinc(II) salt and L in open air at room temperature using appropriate counter anions. The compounds are characterized by microanalytical, spectroscopic, thermal and other physicochemical properties. Structures of 1 and 2 are solved by single crystal X-ray diffraction measurements. Structural study reveals that a µ₃-carbonate binds three zinc(II) centers; each metal center in 1/2 adopts a distorted trigonal bipyramidal geometry with a ZnN₄O chromophore bound by four N atoms of the tetradentate amine (L) and one O atom of carbonate. The trinuclear units in 1/2 are engaged in N–H⋯O/N–H⋯F and C–H⋯F hydrogen bondings leading to different 3D network structures.