Synthesis, structure and properties of supramolecular MnII, CoII, NiII and ZnII complexes containing Salen-type bisoxime ligands

Four supramolecular complexes [MnL1(H2O)2] (1), {[CoL2(OAc)(H2O)]2Co}·5CH3CH2OH (2), {[NiL3(OAc)(CH3OH)]2Ni}·2CH3COCH3·2CH3OH (3) and {[ZnL2(OAc)]2Zn}·CHCl3 (4), have been synthesized and characterized by elemental analyses, IR, UV–Vis spectra and X-ray diffraction techniques. All the complexes have the trinuclear configuration except for MnII complex being mononuclear configuration. Every trinuclear complex contains two acetate ions coordinate to the three metal ions via a familiar M–O–C–O–M (M = Co, Ni, Zn) coordinated mode. Although complexes 1 and 3 display 1D supramolecular chains, the different coordination environments (mononuclear in 1, trinuclear in 3) provoke divergence in the structures and aggregations of the chain subunits. Complex 2 forms a 3D hydrogen-bonding supramolecular networks possessing a channel composing of six O–H···O hydrogen bonds, while complex 4 exhibits a 2D hydrogen-bonding supramolecular networks with the formation of “grottos” occupied by chloroform molecules through intermolecular hydrogen-bond interactions. The spectral properties of the title complexes have been further discussed in detail.

Graphical abstractFour divalent transition metal supramolecular coordination polymers have the trinuclear configuration except for complex 1 being mononuclear configuration. Complexes 1 and 3 display 1D polymeric chains, and complex 2 forms a 3D networks possessing a channel composing of six hydrogen bonds, while 4 exhibits a 2D networks with the formation of “grottos” occupied by chloroform molecules.Figure optionsDownload full-size imageDownload as PowerPoint slide