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DOI: 10.1039/A902572C (Paper) Reference Section for: J. Chem. Soc., Dalton Trans., 1999, 2789-2794

Oxygen versus nitrogen co-ordination in complexes of MoVI and hydroxamate derivatives of α-amino acids: equilibrium, structural and theoretical studies[hair space]†

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Etelka Farkas, Hajnalka Csóka, Gareth Bell, David A. Brown, Laurence P. Cuffe, Noel J. Fitzpatrick, William K. Glass, William Errington and Terence J. Kemp

Abstract

Equilibrium and spectroscopic studies showed that MoVI (MoO42–) reacts with α-aminohydroxamic acids (glycine-, sarcosine-, α-alanine-hydroxamic acids, Glyha, Sarha and α-Alaha) in the acidic pH range to give species involving O,O co-ordination whereas, as the pH is raised, species involving N,N co-ordination are formed. The crystal structure of [MoO2(Glyha)2] confirmed formation of an O,O co-ordination isomer. Theoretical studies of the O,O and N,N isomers of [MoO2(Glyha)2] and [MoO2(Sarha)2] showed the former to be the more stable but the relative closeness of the calculated energies of the isomers is in accord with the solution studies. Histidine hydroxamic acid (Hisha) forms O,O isomers in the acidic pH range but as the pH is raised forms two new isomers, one containing the amino nitrogen protonated and co-ordinated in a tridentate manner using the two hydroxamate oxygen atoms and the imidazole N while the other probably contains protonated imidazole N and is co-ordinated via the amino and hydroxamate nitrogens.

References

  1. A. K. Duhme, Z. Dauter, R. C. Hider and S. Pohl, Inorg. Chem., 1996, 35, 3059 CrossRef CAS.
  2. M. Albrecht, S. J. Franklin and K. N. Raymond, Inorg. Chem., 1994, 33, 5785 CrossRef CAS.
  3. P. Ghosh and A. Chakravorty, Inorg. Chem., 1983, 22, 1322 CrossRef CAS.
  4. D. A. Brown, H. Bogge, R. Coogan, D. Doocey, T. J. Kemp, A. Müller and B. Neumann, Inorg. Chem., 1996, 35, 1674 CrossRef CAS.
  5. E. Farkas, H. Csóka, G. Micera and A. Dessi, J. Inorg. Biochem., 1997, 65, 281 CrossRef CAS.
  6. E. Farkas, K. Megyeri, L. Somsák and L. Kovács, J. Inorg. Biochem., 1998, 70, 41 CrossRef CAS.
  7. D. A. Brown, A. L. Roche, T. A. Pakkanen, T. T. Pakkanen and K. Smolander, J. Chem. Soc., Chem. Commun., 1982, 676 RSC.
  8. B. Kurzak, H. Kozlowski and E. Farkas, Coord. Chem. Rev., 1992, 114, 169 CrossRef CAS.
  9. E. Farkas, E. Kozma, T. Kiss, I. Tóth and B. Kurzak, J. Chem. Soc., Dalton Trans., 1995, 477 RSC.
  10. E. Farkas and I. Sóvágó, in Amino Acids, Peptides and Proteins, Specialist Periodical Report, J. S. Davies(senior reporter), The Royal Society of Chemistry, Cambridge, 1998, vol. 29 Search PubMed.
  11. A. H. Blatt, Organic Synthese, Wiley, New York, 1963 Search PubMed.
  12. H. Irving, M. G. Miles and L. D. Pettit, Anal. Chim. Acta, 1967, 38, 475 CrossRef CAS.
  13. L. Zékány and I. Nagypál, in Computational Methods for the Determination of Stability Constants, ed. D. Legett, Plenum, New York, 1985 Search PubMed.
  14. G. M. Sheldrick, SHELXL 97, Program for the Refinement of Crystal Structures, University of Göttingen, 1997.
  15. Gaussian 94, Revision C.3, M. J. Frisch, G. W. Trucks, H. B. Schlegel, P. M. W. Gill, B. G. Johnson, M. A. Robb, J. R. Cheeseman, T. Keith, G. A. Peterson, J. A. Montgomery, K. Raghavachari, M. A. Al-Laham, V. G. Zakrzewski, J. V. Ortiz, J. B. Foresman, J. Cioslowski, B. B. Stefanov, A. Nanayakkara, M. Challacombe, C. Y. Peng, P. Y. Ayala, W. Chen, M. W. Wong, J. L. Andres, E. S. Replogle, R. Gomperts, R. L. Martin, D. J. Fox, J. S. Binkley, D. J. Defrees, J. Baker, J. P. Stewart, M. Head-Gordon, C. Gonzalez and J. A. Pople, Gaussian, Inc., Pittsburgh, PA, 1995.
  16. K. D. Dobbs and W. J. Hehre, J. Comput. Chem., 1987, 8, 861 CrossRef CAS.
  17. E. Farkas, T. Kiss and B. Kurzak, J. Chem. Soc., Perkin Trans. 2, 1990, 1255 RSC.
  18. E. Farkas and B. Kurzak, J. Coord. Chem., 1990, 22, 145 CAS.
  19. B. Kurzak, H. Kozlowski and P. Decock, J. Inorg. Biochem., 1991, 41, 71 CrossRef CAS.
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