Synthesis and spectral studies of some new dimeric [(mu-Cl)(2)M-2(L)(2) center dot xTHF] [M = Zn(II) and Hg(II)] complexes containing Schiff-base ligands

A series of binuclear Schiff-base complexes of zinc(II) and mercury(II) containing bidentate ligands (HL) [HL = salicylidene-2-methyl-1-aminobenzene (HL1), salicylidene-2-aminopyridine (HL2), and salicylidene-3-nitro-1-aminobenzene (HL3)] with N and O donors have been synthesized by simple metathetic reactions of anhydrous metal chlorides with sodium salts of Schiff bases (in tetrahydrofuran (THF)/MeOH) in equimolar ratio to produce [(mu-Cl)(2)M-2(L)(2) center dot xTHF] [where M = Zn(II) and Hg(II); L = HL1, HL2, and HL3; x = 0 for (1), (4), (6) and x = 2 for (2), (3), (5)]. The main emphasis on the complexes [mu-Cl)(2)M-2(L)(2) center dot 2THF] (2), (3), and (5) is given due to their five-coordinate environment around metal ions. The complexes have been characterized by elemental analyses (M, Cl, C, H, N), melting point, and spectral (FT-IR, H-1-NMR, and C-13-NMR) studies. The structural composition of the complexes has been determined by FAB-MS spectral studies. FAB-MS showed the isotopic molecular ion peak [M+] and fragments supporting the formulation. Powder X-ray diffraction study of 6 is also reported showing the crystallite size (404.5 angstrom) of the complex.