Crystal Structures and Fluorescence Properties of Cu(II)/Zn(II) Complexes with a Semicarbazone Ligand Bearing Pyrazine Unit

Two complexes, namely, [Cu-2(L)(2)Br-2] center dot CH3OH (1) and [Zn-2(L)(2)(CH(3)C0O)(2)] center dot 2CH(3)OH (2) (HL =1-(3ethylpyrazin-2-yDethylidene-4-phenylsemicarbazide) have been synthesized and characterized by single crystal Xray diffraction, elemental analysis and IR spectroscopy. In complex 1, the center Cu(II) ion with a distorted square pyramid coordination geometry is coordinated by one tridentate deprotonated semicarhazone with N2O donor set and two mu(2)-bridged bromide anions. The coordination geometry of the Zn(II) ion in complex 2 is same as that of the Cu(II) ion in complex 1, while with N2O3 donor set. In addition, two acetate anions in complex 2 exhibit different coordination modes, one of which is bidentate bridge (mu-OCO), while the other one is oxygen bridge (mu-O). In the methanol solution. both complexes exhibit the intra-tigand emission. CCDC: 1516162. 1: 1516163, 2.