Synthesis, crystal structure and spectroscopy studies of a novel five-coordinated Zn(II) ion complex with l-tyrosine and imidazole

The new five-coordination zinc(II) complex of formula [Zn(Im)(l-tyr)2]2·5H2O consisting of l-tyrosine (l-tyr) and imidazole (Im) molecules as ligands was prepared as crystals and characterized by X-ray diffraction, IR-FIR vibrational and UV–Vis electronic spectroscopy. The [Zn(Im)(l-tyr)2]2·5H2O complex crystallizes in the orthorhombic crystal system and P21212 space group. The [ZnN2N′O2] chromophore has distorted bipiramidal geometry with value of τ parameter 0.7. The sensitive intra and inter-molecular hydrogen bonds created the layers arrangement and the “pseudo-baskets” fashion. The intraligand charge transfer (ILCT) π–π∗ and π–π∗ transitions in the ligands molecule are corresponded to the intensity bands in the UV–Vis region.

The [Zn(Im)(l-tyr)2]2·5H2O (1) where l-tyr = l-tyrosine and Im = imidazole complex has been obtained in crystalline form and studied by X-ray crystallography and spectroscopic methods (FIR, IR, UV–Vis). The complex 1 shows the distorted bipyramidal geometry around Zn2+ with value of τ parameter 0.7. The intra and inter-molecular hydrogen bonds created the: “pseudo-basket” fashion.Figure optionsDownload as PowerPoint slideHighlights
► Synthesis, structure and spectroscopic properties of l-tyrosinato zinc(II) complex.
► The Zn2+ ion environment shows a slight distorted trigonal bipyramidal geometry.
► The unique “pseudo-basket” fashions are formed by inter-molecular hydrogen bonds.