An investigation of the structures, properties and possible applications of complexes of metals with organotellurium compounds

Abstract

Organic telluridecomplex forming ability was investigated. It is found that tellurides form quite stable complexes with metals of class (b) or softish character. Copper(I), rhodium(III) and rhodium(I) complexes with diaryltellurides were synthesised. Their structure, properties and uses were investigated with the help of various physical techniques. Copper(1) halides and tellurides were found to form complexes with definite compositions irrespective of the ratio of metal: ligand used. A 2:1 ligand to metal ratio was preferentially formed among the copper(I) complexes. The structures of these copper(I) compounds were found to range from tetrahedral, fourcoordinated copper(I) halogen bridged dimers, trigonal planar and three coordinated copper(I) halogen bridged dimers. The copperhalogen stretching vibrations v(Cu - X); (X = Cl, Br, I) were found to be rather low compared with the available literature values. Rhodium(III) halides with tellurides were found to form complexes of the type ML 3X33 (L = diaryltelluride; X = Cl, Br) to which a configuration was assigned with the aid of far infra-red and n.m.r. spectroscopy. mer RhL 4X, was found to form in good yield under dinitrogen. The preparation carried our under air yielded the complex fac RhL 3X. in lower yield. Reactions using [Rh(PhaTe) C1 3] as a synthetic intermediate in preparing complexes of the type [Rh(Ph,Te) (chelate )C1,]; (chelate = 2,2'bipyridyl, 1,10'phenanthroline, di-2-pyridylketone, di-2-pyridylamine) were carried out. A rhodium(I) complex with telluride was found to be stable only in the presence of CO; a complex formulated as -[Rh(PhTe),(CO)C1] was synthesised. Reactions using telluride to stabilise rhodium(I) compounds in the presence of ethanolic KOH and borohydride were unsuccessful. Reactions to test the complex Rh(PhoTe) C1, as a homogeneous hydrogenation catalyst were carried out. It was found that Rh (PhoTe) C1, did not catalyse the homogeneous hydrogenation reaction contrary to the complexes (RhL.C14); (L = Et S, (PhcH.),S ) which are known to be active. The role of di-2-pyridylketone as ligand was investigated. Some complexes of cobalt, iron, nickel and copper with di-2- pyridylketone were synthesised and characterised by various techniques. An explanation for the anomolous magnetic behaviour of cobalt complex reported by a previous worker is given. Tris complexes of di-2-pyridylketone were found to exist. The ligand field parameters of some complexes are given, and di-2-pyridylketone was found to be a weak field ligand. It was noted that under some circumstances the carbonyl group of the ligand became readily aquated or alcoholated. The ease of formation of these acetal or hemicetal deriviatives is discussed and it is concluded that, contrary to the previous suggestion, steric strain within the carbonyl ligand need not be a major cause. All complexes prepared are discussed in terms of their analytical data and spectra, including in the case of iron(II) and iron(III) complexes their 57 Fe Mössbauer spectra. In one case good evidence for an(N,0)mode of coordination for di-2-pyridylketone was found.

Divisions: College of Engineering & Physical Sciences > School of Infrastructure and Sustainable Engineering > Chemical Engineering & Applied Chemistry
Additional Information: Copyright © Rattanaphani, 1973. V. Rattanaphani asserts their moral right to be identified as the author of this thesis. This copy of the thesis has been supplied on condition that anyone who consults it is understood to recognise that its copyright rests with its author and that no quotation from the thesis and no information derived from it may be published without appropriate permission or acknowledgement. If you have discovered material in Aston Publications Explorer which is unlawful e.g. breaches copyright, (either yours or that of a third party) or any other law, including but not limited to those relating to patent, trademark, confidentiality, data protection, obscenity, defamation, libel, then please read our Takedown Policy and contact the service immediately.
Institution: Aston University
Uncontrolled Keywords: structures,properties,applications,complexes metals,organotellurium compounds
Last Modified: 08 Dec 2023 08:03
Date Deposited: 13 Jan 2011 12:01
Completed Date: 1973
Authors: Rattanaphani, Vichitr

Export / Share Citation


Statistics

Additional statistics for this record