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

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.

Two trinuclear zinc(II) carbonato compounds [Zn3(μ3-CO3)(L)3](ClO4/PF6)4 (1/2) [L = N,N′-bis(3-aminopropyl)-1,2-ethanediamine] have been isolated in an open air using zinc(II) salts and L, and X-ray crystallographically characterized. 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.Figure optionsDownload as PowerPoint slideHighlights
► Two trinuclear zinc(II) carbonato compounds are isolated.
► X-ray structural analyses reveal interesting μ3-carbonato bridging motifs.
► Fixation of CO2 and transformation to CO32− from the atmosphere are established.
► Thermogravimetric analyses show their thermal stability and decomposition pattern.