SYNTHESES AND CHARACTERIZATION OF SOME NEW MIXED-LIGAND LEAD(H) COMPLEXES, Pb(en)(CH_3COO)X (X = NCS~-, ClO_4~- OR NO_3~-); CRYSTAL STRUCTURE OF [Pb(en)(CH_3COO)(NO_3)]_n (en = ETHANE-1,2-DIAMINE)

摘要

Lead(II) complexes with ethane-1,2-diamine (en) containing two different anions, [Pb(en)(CH_3COO)X] (X = NCS~-, ClO_4~- or NO_3~-), have been synthesized and characterized by CHN elemental analysis, IR, ~1H NMR, ~(13)C NMR and ~(207)Pb NMR spectroscopy. Single crystal X-ray data for [Pb(en)(NO_3)(CH_3COO)] show the complex to be polymeric. The Pb atom has an unsymmetrical five-coordinate geometry and the weak interaction of lead(II) with oxygen atoms of adjacent molecule produces polymeric units in the solid state. The en ligand and counter ions in this complex exhibit a coordination gap around the Pb(II) ion, occupied possibly by a stereoactive lone pair of electrons on lead(II), that may be affected by intermolecular hydrogen bonding.