New co-ordination compounds derived from barium(II) and the anionic 4-tert-butylacetyl-3-methyl-1-phenylpyrazol-5-onate ligand (Q^–). Crystal and molecular structure of [Ba₂Q₄(H₂O)₄], [Ba₂Q₄(Him)₄], [BaQ₂(tetraglyme)] (tetraglyme = 2,5,8,11,14-pentaoxapentadecane) and [BaQ₂(phen)₂]

Abstract

By reaction of 4-tert-butylacetyl-3-methyl-1-phenylpyrazol-5-one (HQ) with metallic Ba in MeOH the dinuclear derivative [{BaQ₂(H₂O)₂}₂] 1 has been synthesized. It contains two barium atoms each eight-co-ordinated by a terminal bidentate Q ligand, two bridging double chelating Q ligands and two molecules of water. When the reaction of HQ with Ba was carried out in the presence of mono-, bi- or poly-dentate O- or N-donor ligands, derivatives of formula BaQ₂L_n(H₂O)_m have been obtained, depending on the nature of the ancillary ligand and reaction conditions employed [L = 2,5,8,11,14-pentaoxapentadecane (tetraglyme), 2,5,8,11-tetraoxadodecane (triglyme), 2,5,8-trioxanonane (diglyme), 2,2′∶6′,2″-terpyridine (terpy), 2,3-bis(2-pyridyl)pyrazine (Pypy), n = 1, m = 0 or 1; L = imidazole (Him), 1-methylimidazole (1-MeIm), 2-methylimidazole (2-MeImH), 1,10-phenanthroline (phen), 2,2′-bipyridyl (bipy), 2,9-dimethyl-1,10-phenanthroline (Cupr) and triphenylphosphine oxide (PPh₃O), n = 2, m = 0 or 1]. In the nine-co-ordinated [BaQ₂(tetraglyme)] the Ba atom is co-ordinated by all the five oxygen atoms of tetraglyme and by four oxygen atoms of two bidentate Q whereas the co-ordination number of barium in [BaQ₂(phen)₂] is eight due to four oxygen atoms of the two Q ligands and four nitrogen atoms of the two 1,10-phenanthrolines. The derivative [{BaQ₂(Him)₂}₂] is dinuclear with the Ba atoms linked by two double chelating Q ligands. The imidazoles complete the co-ordination number of Ba to 8. The compound [(BaQ₂)_n] has been obtained by heating derivative 1 in vacuo at 100 °C, whereas the 1∶1 adduct [BaQ₂(phen)] was obtained only when [(BaQ₂)_n] was treated in diethyl ether with an equimolar solution of phen. When a methanol solution of [BaQ₂(Pypy)] reacts with an equimolar methanol solution of CdCl₂ scrambling of the ligand occurs and derivatives 1 and [(CdCl₂)₂(Pypy)] are obtained. All the compounds obtained have been characterised by IR and far-IR data, conductivity and vaporimetric molecular weight measurements, ¹H NMR and in some cases also variable temperature ¹H NMR spectra. Comparison was made with structural and spectroscopic data reported for related barium(II) compounds.

References

1. T. Ozawa, Thermochim. Acta, 1991, 174, 185.
2. H. Zama and Sh. Oda, Jpn. J. Appl. Phys., 1990, 29, L1072.
3. A. D. Berry, D. K. Gaskill, R. T. Holm, E. J. Cukauskas, R. Kaplan and R. L. Henry, Appl. Phys. Lett., 1988, 52, 1743.
4. A. Glezies, A. Drozdov and S. Troyanov, Koord. Khim., 1994, 20, 922.
5. A. Drozdov and S. Troyanov, J. Chem. Soc., Chem. Commun., 1993, 1619.
6. D. C. Bradley, M. Hasan, M. B. Hursthouse, M. Motevalli, O. F. Z. Khan, R. C. Pritchard and J. O. Williams, J. Chem. Soc., Chem. Commun., 1992, 575.
7. R. E. Sievers, S. B. Turnipseed, L. Huang and A. F. Lagalante, Coord. Chem. Rev., 1993, 128, 285.
8. E. C. Okafor and B. A. Uzoukwu, Synth. React. Inorg. Met.-Org. Chem., 1991, 21, 1375.
9. E. C. Okafor, P. U. Adiukwu and B. A. Uzoukwu, Synth. React. Inorg. Met.-Org. Chem., 1993, 23, 97.
10. C. Pettinari, F. Marchetti, A. Cingolani, D. Leonesi, E. Mundorff, M. Rossi and F. Caruso, J. Organomet. Chem., 1998, 557, 187 and refs. therein.
11. C. Pettinari, F. Accorroni, A. Cingolani, F. Marchetti, A. Cassetta and L. Barba, J. Organomet. Chem., 1998, 566, 187.
12. F. Marchetti, C. Pettinari, A. Cingolani, D. Leonasi, M. Camalli and A. Pifferi, Polyhedron, 1996, 15, 3835.
13. F. Marchetti, C. Pettinari, A. Cingolani, D. Leonesi, A. Drozdov and S. Troyanov, J. Chem. Soc., Dalton Trans., 1998, 3325.
14. Y. A. Zolotov, N. M. Kuzmin and in Metal Extraction with Acylpyrazolones, Izdat Nauka, Moscow, 1977.
15. E. C. Okafor, Z. Naturforsch., Teil B, 1981, 36, 213.
16. S. Umetani and H. Freiser, Inorg. Chem., 1987, 26, 3179.
17. E. C. Okafor and B. A. Uzoukwu, Radiochim. Acta, 1990, 51, 167.
18. K. Venkataraman, in The Chemistry of Dyes, Academic Press, New York, 1952, vol. 1.
19. M. F. McMahon, K. C. Molloy, B. A. Omotowa and M. A. Mesubi, J. Organomet. Chem., 1996, 511, 227.
20. M. F. McMahon, K. C. Molloy, B. A. Omotowa and M. A. Mesubi, J. Organomet. Chem., 1996, 525, 239.
21. D. S. Schulz, B. J. Hinds, C. L. Stern and T. J. Marks, Inorg. Chem., 1993, 32, 249.
22. T. J. Marks, Pure Appl. Chem., 1995, 67, 313.
23. B. A. Uzoukwu, P. U. Adiukwu, S. S. Al-Juaid, P. B. Hitchcock and J. D. Smith, Inorg. Chim. Acta, 1996, 250, 173.
24. S. R. Drake, S. A. S. Miller and D. J. Williams, Inorg. Chem., 1993, 32, 3227.
25. G. M. Sheldrick, SHELXS 86, University of Göttingen, 1986.
26. G. M. Sheldrick, SHELXL 93, University of Göttingen, 1993.
27. A. Drozdov and S. Troyanov, Polyhedron, 1993, 12, 2973.
28. S. Roffia, M. Marcaccio, C. Paradisi, F. Paolucci, V. Balzani, G. Denti, S. Serroni and S. Campagna, Inorg. Chem., 1993, 32, 3003.
29. A. Drozdov and S. Troyanov, Koord. Khim., 1994, 20, 171.
30. S. R. Drake, M. B. Hursthouse, K. M. A. Malik and S. A. S. Miller, Inorg. Chem., 1993, 32, 4653.
31. K. Nakamoto, Infrared and Raman Spectra of Inorganic and Coordination Compounds, 4th edn., Wiley Interscience, New York, 1986, ch. III, pp. 208–213.
32. K. Nakamoto, Infrared and Raman Spectra of Inorganic and Coordination Compounds, 4th edn., Wiley Interscience, New York, 1986, ch. III, pp. 259–268.
33. W. S. Rees, M. W. Carris and W. Hesse, Inorg. Chem., 1991, 30, 4479.
34. A. Drozdov and S. Troyanov, Main Group Met. Chem., 1996, 19, 547.
35. N. Kuzmina, A. Drozdov, T. Zotova, G. Kupryanova, A. Pisarevsky and Yu. Struchkov, Koord. Khim., 1994, 20, 743.
36. N. Kuzmina, V. Ivanov, S. Troyanov and L. Martynenko, J. CVD, 1994, 3, 32.