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DOI: 10.1039/A702960H (Paper) Reference Section for: J. Chem. Soc., Dalton Trans., 1997, 2875-2886

Triorganosiloxy and tetraphenyldisiloxydiolate complexes of the heavier alkaline-earth metals. Crystal structures of [Sr3(tmhd)3(OSiPh3)3] ·0.5C6H5Me (tmhd = 2,2,6,6-tetramethylheptane-3,5-dionate) and [Sr3{O(SiPh2O)2}3 (tetraglyme)2]·0.5C6H5Me [tetraglyme = CH3O(CH2CH2O)4CH3 ]

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Ian Baxter, Jawwad A. Darr, Simon R. Drake, Michael B. Hursthouse, K. M. Abdul Malik and D. Michael P. Mingos

Abstract

Strontium or barium metal granules reacted with an excess of HOSiMe2But in an ammoniacal toluene solution at -40 °C to produce the corresponding [M(OSiMe2But)2]n. The strontium complex was also obtained from silanolysis of the strontium ethoxide [{Sr(OEt)2(HOEt)4}n] with an excess of HOSiMe2But in hot toluene solution. Similarly, the reaction of [{Sr(OEt)2(HOEt)4}n] in hot toluene, with 1 molar equivalent of HOSiPh3 and Htmhd (2,2,6,6-tetramethylheptane-3,5-dione) yielded the trimeric complex [Sr3(tmhd)3(OSiPh3)3] ·0.5C6H5Me. The reaction of strontium or barium metal granules with 2 molar equivalents of diphenylsilanediol [Ph2Si(OH)2] in ammoniacal toluene solution at -40 °C yielded the polymeric complexes [{M[O(SiPh2O)2](H2O)(NH3 )x}n] [M = Ca (x = 0.3), Sr (x = 1) or Ba (x = 0.3)]. Similar reactions for strontium and barium in the presence of an excess of hmpa [OP(NMe2)3] produced [Sr3{O(SiPh2O)2}3 (hmpa)5]·C6H5Me and [Ba3{O(SiPh2O)2}3 (hmpa)5(H2O)], respectively. Alternatively, when these reactions were performed in the presence of tetraglyme [CH3O(CH2CH2O)4CH3 ] the water- and NH3-free complexes [M3{O(SiPh2O)2}3 (tetraglyme)2]·0.5C6H5Me were obtained (M = Sr or Ba). All complexes have been characterised by elemental analyses and IR, NMR (1H, 13C and 29Si, in selected cases 31P) spectroscopy and also by TGA/DSC studies. The complexes [Sr3(tmhd)3(OSiPh3)3] ·0.5C6H5Me and [Sr3{O(SiPh2O)2}3 (tetraglyme)2]·0.5C6H5Me have been characterised by X-ray crystallography. The structure of the former reveals a trimer of strontium cations stabilised by three tmhd ligands, and one µ- and two µ3-bridging triphenylsiloxy ligands. Relatively short Sr · · ·[hair space] [hair space]C (methyl) and Sr · · ·[hair space] [hair space]C (phenyl) contacts have also been identified in this compound. In contrast, the three strontium cations in the latter are arranged in an almost linear array within a Sr3O9Si6 core.

References

  1. M. G. Voronkov, E. A. Maletina and V. K. Roman, in Heterosiloxanes Volume 1: Derivatives of Non-Biogenic Elements, Harwood Academic, London, 1988 Search PubMed.
  2. F. T. Edelmann, Angew. Chem., Int. Ed. Engl., 1992, 31, 586 CrossRef.
  3. D. C. Bradley, Chem. Rev., 1989, 89, 1317 CrossRef CAS.
  4. K. G. Caulton, M. H. Chisholm, S. R. Drake and W. E. Strieb, Inorg. Chem., 1990, 29, 2707 CrossRef CAS.
  5. K. G. Caulton, M. H. Chisholm, S. R. Drake and W. E. Strieb, Angew. Chem., Int. Ed. Engl., 1990, 29, 1483 CrossRef.
  6. J. A. Darr, Ph.D. Thesis, University of London, 1995.
  7. B. G. Govenlock, W. E. Lindsell and B. Singh, J. Chem. Soc., Dalton Trans., 1978, 657 RSC.
  8. F. G. Cloke, P. B. Hitchcock, M. F. Lappert, G. A. Lawless and B. C. Royo, J. Chem. Soc., Chem. Commun., 1991, 724 RSC and refs. therein.
  9. D. Mootz, A. Zinnius and B. Böttcher, Angew. Chem., Int. Ed. Engl., 1969, 8, 379 CrossRef.
  10. M. Krumpolc and V. Chalovsky, Collect. Czech. Chem. Commun., 1972, 32, 1392.
  11. R. Han and G. Parkin, Polyhedron, 1990, 9, 2655 CrossRef CAS; R. Han and G. Parkin, J. Am. Chem. Soc., 1992, 114, 748 CrossRef CAS.
  12. S. R. Drake and D. J. Otway, Main Group Metal Chem., 1991, 14, 243 Search PubMed.
  13. K. G. Caulton, M. C. Chisholm, S. R. Drake, K. Folting and W. E. Strieb, Inorg. Chem., 1992, 31, 3205 CrossRef CAS.
  14. J. A. Darr, S. R. Drake, M. B. Hursthouse and K. M. A. Malik, Inorg. Chem., 1993, 32, 5704 CrossRef CAS.
  15. I. Baxter, J. A. Darr, S. R. Drake, M. B. Hursthouse, D. M. P. Mingos and K. M. A. Malik, unpublished work.
  16. J. D. Foulon, P. Miele and N. Hovnanian, Z. Kristallogr., 1994, 209, 282 CAS.
  17. M. Motevalli, D. Shah, S. A. A. Shah and A. C. Sullivan, J. Chem. Soc., Chem. Commun., 1994, 2427 RSC.
  18. J. A. Darr, S. R. Drake, A. M. Z. Slawin and D. J. Williams, J. Chem. Soc., Chem. Commun., 1993, 866 RSC.
  19. V. C. Arunasalam, Ph.D. Thesis, University of London, 1995; D. J. Otway, Ph.D. Thesis, University of London, 1995.
  20. Md. A. Hussain, M. B. Hursthouse, Md. A. Mazid and A. C. Sullivan, J. Chem. Soc., Chem. Commun., 1988, 1305 RSC.
  21. Md. A. Hussain, M. B. Hursthouse, Md. A. Mazid, A. Ibrahim and A. C. Sullivan, J. Chem. Soc., Dalton Trans., 1989, 2347 RSC.
  22. C. G. Barraclough, D. C. Bradley, J. Lewis and I. M. Thomas, J. Chem. Soc., 1961, 2601 RSC.
  23. K. G. Caulton, P. S. Coan, K. Folting, M. J. McGeary and R. C. Wedlich, Polyhedron, 1992, 11, 2459 CrossRef CAS.
  24. S. R. Drake, M. B. Hursthouse, K. M. A. Malik and D. J. Otway, J. Chem. Soc., Dalton Trans., 1993, 2883 RSC.
  25. T. P. Hanusa, Chem. Rev., 1993, 93, 1023 CrossRef CAS.
  26. J. A. Darr, S. R. Drake, M. B. Hursthouse, K. M. A. Malik, S. A. S. Miller and D. M. P. Mingos, J. Chem. Soc., Dalton Trans., 1997, 945 RSC.
  27. S. R. Drake, M. B. Hursthouse, K. M. A. Malik and S. A. Miller, Polyhedron, 1993, 13, 1621 CrossRef CAS.
  28. J. E. Huheey, Inorganic Chemistry: Principles of Structure and Reactivity, Harper and Row, New York, 3rd edn., 1983 Search PubMed.
  29. See, for example, P. D. Lickiss, S. A. Litster, A. D. Redhouse and C. J. Wisener, J. Chem. Soc., Chem. Commun., 1991, 173 Search PubMed; P. D. Lickiss, A. D. Redhouse, K. Rózga, W. A. Stañczyk and R. J. Thompson, J. Organomet. Chem., 1993, 453, 13 RSC.
  30. M. A. Hossain, M. B. Hursthouse and K. M. A. Malik, Acta Crystallogr., Sect. B, 1978, 35, 2039.
  31. P. S. Coan, L. G. Hubert-Pfalzgraf and K. G. Caulton, Inorg. Chem., 1992, 31, 1262 CrossRef CAS.
  32. P. D. Lickiss and K. M. Stubbs, J. Organomet. Chem., 1991, 421, 171 CrossRef CAS.
  33. N. P. C. Walker and D. Stuart, Acta Crystallogr., Sect. A, 1983, 39, 158 CrossRef; adapted for FAST geometry by A. I. Karaulov, University of Wales, Cardiff, 1991.
  34. G. M. Sheldrick, Acta Crystallogr., Sect. A, 1990, 46, 467 CrossRef.
  35. G. M. Sheldrick, SHELXL 93, program for crystal structure refinement, University of Göttingen, 1993.
  36. H. D. Flack, Acta Crystallogr., Sect. A, 1983, 39, 876 CrossRef.
  37. K. Davies, SNOOPI, program for crystal structure drawing, University of Oxford, 1983.
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