Synthesis, structure and characterization of two novel mercury(II) complexes with N-(2-aminoethyl)piperazine

Two novel mercury(II) complexes [Hg-II(mu(2)-LH)Cl-2](2)[Hg-2(II)(mu(2)-Cl)(2)Cl-4](.)2H(2)O (1) and [Hg-4(II)(mu(3)-Cl)(2)(mu(2)-Cl)(2)Cl-6] (2) have been synthesized by the reaction of N-(2-aminoethyl)piperazine (L) with HgCl2 under different pH conditions. I and 2 were characterized by single-crystal X-ray diffraction analysis. The results reveal that in I there exist discrete mononuclear [Hg-II(mu(2)-LH)Cl-2](+) units and binuclear [Hg-2(II)(mu(2)-Cl)(2)Cl-4](2+) unit while in 2 there exist the rarely reported discrete cylic tetranuclear [Hg-4(II)(mu(3)-L)(2)(mu(2)-Cl)(2)Cl-6] cluster units, which are both assembled into 3D supramolecular structures via extensive hydrogen-bonding interactions. 1 and 2 were also characterized by element analysis, FT-IR and luminescence spectra.