Synthesis and characterization of some Schiff base metal complexes

Abstract

The formation of novel complexes of selected transition metals with a Schiff base ligand derived from salicylaldehyde and aminopropanol is reported. The metal chlorides of platinum(II), palladium(II), cadmium(II) and mercury(II), were reacted with 2-[(3-hydroxypropylimino)methyl]phenol using several methods in an attempt to form new complexes. The products that were obtained were analysed by means of several methods that included elemental analysis, magnetic susceptibility, ultraviolet visible, infrared, and n.m.r. spectroscopy. The elemental analysis indicated that the products were Pt3(C10H1202N)4; [Pd(C10H1202N)2]n; [CdC10H1202N)2] 2 +[2Clf .5H20; and [Hg(C3H90N)]2+[2Cl)2-. Magnetic susceptibility measurement showed that all the complexes were diamagnetic and this suggested a square planar geometry. The n.m.r. spectra for the platinum(II) and the cadmium(II) complexes indicated that these products were bidentate whereas the spectrum obtained for the palladium(II) complex indicated that a tridentate complex had been obtained. Elemental analysis and infra red spectoscopy also suggested that in the case of the palladium(II) complex a polymer may have been obtained where the monomer units are joined together through phenoxy- bridging. Qualitative analysis showed that the chloride ion of the metal salts was retained in the d10 metal complexes but had been lost in the d8 complexes, thereby indicating that the former products are ionic. Mercury(II) chloride was found to complex with only the aliphatic part of the Schiff base ligand with bonding taking place at the imino nitrogen. The potential use of these Schiff base metal complexes as catalysts in the production of polyethylene was also discussed but a study of such properties was not carried out.