Advertisement

Russian Chemical Bulletin

, Volume 45, Issue 7, pp 1734–1739 | Cite as

Influence of the redox state of the ligand on the dealkylation of substituted methylcobaloximes in the presence of heavy metal ions

  • E. R. Milaeva
  • A. V. Androsova
  • O. V. Polyakova
  • A. I. Prokof'ev
  • V. S. Petrosyan
Organometallic Chemistry
  • 32 Downloads

Abstract

The synthesis of cobaloxime and methylcobaloxime containing sterically hindered 2,6-di-tert-butylphenol fragments in the ligand is described. Spectral studies of the demethylation of methylbis(dimethylglyoximato)cobalt (1a), methylbis(diphenylglyoximato)cobalt (1b), methylbis[methyl-(3,5-di-tert-butyl-4-hydroxyphenyl)glyoximato]cobalt (1c) pyridinates were carried out in the presence of Cd2+, Hg2+, Sn4+, Pb2+, and Pb4+ ions, The free radical forms of the complexes containing a phenoxy radical W the ligand are formed during oxidation. The ESR spectra are given. The unpaired electron in the periphery of the methylcobaloxime ligand1c interacts with the Co-CH3 fragment through the conjugated systems, enhancing the donating properties of the equatorial ligand of the complex, which leads to the rapid cleavage of the Co-C bond. Therefore the demethylation of methylcobaloxime in the presence of heavy metal ions occurs in a significantly shorter time.

Key words

cobaloxime methylcobaloxime heavy metals sterically hindered phenol free radical ligand demethylation 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Organometallic Compounds in the Environment, Ed. P. J. Craig, Longman, UK, 1986.Google Scholar
  2. 2.
    The Biological Alkylation of the Heavy Elements, Ed. P. J. Craig, Royal Soc. Chem., London, 1988.Google Scholar
  3. 3.
    J. S. Thayer and F. E. Brinckman,Adv. Organomet. Chem., 1982,20, 314.Google Scholar
  4. 4.
    G. N. Schrauzer,Acc. Chem. Res., 1968,1, 97.Google Scholar
  5. 5.
    Weygand-Hilgetag,Organisch-Chemische Experimentierkunst, T. A. Barth Verlag, Leipzig, 1964.Google Scholar
  6. 6.
    G. N. Schrauzer and R. J. Windgassen,J. Am. Chem. Soc., 1966,88, 3738.Google Scholar
  7. 7.
    V. V. Ershov, G. A. Nikiforov, and A. A. Volod'kin,Prostransrvenno zatrudnennye fenoly [Sterically Hindered Phenols], Khimiya, Moscow, 1972, (in Russian).Google Scholar
  8. 8.
    A. Chakravorty,Coord. Chem. Rev., 1974,13, 1.Google Scholar
  9. 9.
    D. G. Brown,The Chemistry of Vitamin B 12 and Related Inorganic Model Systems, inProgr. Inorg. Chem., 1972, 177.Google Scholar
  10. 10.
    G. N. Schrauzer, L. P. Lee, and J. W. Sibert,J. Am. Chem. Soc., 1970,92, 2997.PubMedGoogle Scholar
  11. 11.
    M. V. Nekhoroshev, V. B. Panov, and O. Yu. Okhlobystin,Zh. Org, Khim., 1977,13, 662 [Org. Chem. USSR, 1977,13 (Engl. Transl)].Google Scholar

Copyright information

© Plenum Publishing Corporation 1996

Authors and Affiliations

  • E. R. Milaeva
    • 1
  • A. V. Androsova
    • 1
  • O. V. Polyakova
    • 1
  • A. I. Prokof'ev
    • 2
  • V. S. Petrosyan
    • 1
  1. 1.Department of ChemistryM. V. Lomonosov Moscow State UniversityMoscowRussian Federation
  2. 2.A. N. Nesmeyanov Institute of Organoelement CompoundsRussian Academy of SciencesMoscowRussian Federation

Personalised recommendations