Syntheses and spectral properties of iron(II) complexes with tetraaza(12) macrocyclic ligands

The iron(II) complexes of 1,4,7,10-tetraazacyclododeca-1,3-diene (L1) and 2,3-dimethyl-1,4,7,10-tetraazacyclododeca-1,3-diene (L2) have been prepared and studied by means of vibrational and electron spin resonance (esr) spectroscopy. Based on elemental analysis and spectroscopic properties, the structure for the complexes are proposed as follows: square pyramidal for [Fe(L1-2H) H2O] and [Fe(L2-2H) H2O] and distorted octahedral for [Fe(L1-H) Py (OAC)]. Keywords: Tetraazamacrocycle, Iron(II) complex, Vibrational, esr, spectra. [Global Jnl Pure & Appl. Sci. Vol.9(3) 2003: 325-330

Syntheses and spectroscopic properties of mercury(II) and nickel(II) complexes of BIS(N-Phenyl thiourea)

Mercury(II) complex, [Hg2(BPTU-2H)Cl2] and nickel(II) complex, [Ni(BPTU-H)2] were prepared by reacting Bis(N-phenylthiourea), BPTU, with mercury(II) chloride and nickel(II) acetate respectively. The complexes were characterized by IR, diffuse reflectance, 1H NMR spectra and elemental analysis. BPTU acts as monoanionic bidentate chelating agent in nickel(II) complex, coordinating through thiolato sulphur and hydrazinic nitrogen atoms. Its coordination nature differs in mercury(II) complex, where it acts as dianionic bis(bidentiate) chelating agent, coordinating through thiolato sulphur and hydrazinic nitrogen atoms to two mercury(II) ions simultaneously. on the basis of analysis and spectral properties, Ni(BPTU-H)2 has been tentatively assigned square planar geometry. The [Hg2(BPTU-2H)Cl2] appears to have binuclear structure having triangular coordination centres around mercury(II) cations. KeyWords: Bis(N-phenylthiourea), mercury(II) complex, nickel(II) complex, IR,1H NMR, electronic spectra. [Global Jnl Pure & Appl. Sci. Vol.9(3) 2003: 351-358