New functionalized bis(pyrazol-1-yl)methane ligands. Synthesis, spectroscopic characterization of early and late transition metal complexes containing a functionalized N,N or P,P-chelate bis(5-diphenylphosphinopyrazol-1-yl)methane ligand

(Note: The full text of this document is currently only available in the PDF Version )

Antonio Antiñolo, Fernando Carrillo-Hermosilla, Enrique Díez-Barra, Juan Fernández-Baeza, Maria Fernández-López, Agustin Lara-Sánchez, Andrés Moreno, Antonio Otero, Ana Maria Rodriguez and Juan Tejeda


Abstract

The multistep syntheses of the novel functionalized bis(pyrazol-1-yl)methane ligands, bis(5-diphenylphosphinopyrazol-1-yl)methane (bppzm) 1, bis(5-diphenylphosphinopyrazol-1-yl)trimethylsilylmethane (bppztm) 2 and bis(2-diphenylphosphinoimidazol-1-yl)methane (bpizm) 3, have been studied. The coordinative capacity of the bppzm ligand towards a variety of early and late metal fragments was evaluated and seven metallacycles were isolated. The complex [{NbCl3(dme)}n] (dme = 1,2-dimethoxyethane) reacted with an excess of bppzm to give the binuclear complex [{NbCl3(bppzm)}2] 4, and in the same way the reaction of the mononuclear species [NbCl3(dme)(RC[triple bond, length half m-dash]CR′)] with 1 gave the appropriate [NbCl3(bppzm)(RC[triple bond, length half m-dash]CR′)] complexes (R = R′ = Ph 5; R = R′ = SiMe3 6; R = Ph, R′ = Me 7; R = Ph, R′ = SiMe3 8). In all these niobium complexes, 1 behaves as an N,N chelate ligand. Compound 1 reacts with [MCl2(PhCN)2] (M = Pd, Pt) to yield the complexes [MCl2(bppzm)] (M = Pd 9, Pt 10), where a P,P chelate behaviour for 1 was observed. A dynamic conformation of the six- and eight-membered metallacycles formed in the complexes was observed and variable-temperature NMR studies were carried out. Finally, the molecular structure of complex 10 was determined crystallographically and a distorted square-planar geometry was found in which a proton (Hendo) of the bridging methylene is in close proximity to the metal centre in the boat–boat conformation of the metallacycle.


References

  1. E. M. Miller and B. L. Shaw, J. Chem. Soc., Dalton Trans., 1974, 480 RSC; J. Powell, A. Kuksis, C. J. May, S. C. Nyburg and S. J. Smith, J. Am. Chem. Soc., 1981, 103, 5941 CrossRef CAS; W. Keim, New J. Chem., 1987, 11, 531 Search PubMed; U. Klabunde, T. H. Tulip, D. C. Roe and S. D. Ittel, J. Organomet. Chem., 1987, 334, 41 CrossRef; E. Lindner and H. Norz, Chem. Ber., 1990, 123, 459 CAS; H. Werner, A. Stark, M. Schultz and J. Wolf, Organometallics, 1992, 11, 1126 CrossRef CAS; D. Soulivong, D. Matt, R. Ziessel, L. Douce and R. Deschenaux, Tetrahedron Lett., 1993, 34, 1151 CrossRef CAS; D. Matt, N. Sutter-Beydoun, J.-P. Brunette, F. Balegroune and D. Grandjean, Inorg. Chem., 1993, 32, 3488 CrossRef CAS.
  2. See, for example: T. B. Rauchfuss, F. T. Patino and D. M. Roundhill, Inorg. Chem., 1975, 3, 652 Search PubMed; F. Mathey and F. Mercier, J. Organomet. Chem., 1979, 177, 255 CrossRef; D. Sinou, Bull. Soc. Chim. Fr., 1987, 3, 480 CrossRef CAS; O. Stelzer and K.-P. Langhans, The Chemistry of Organophosphorus Compounds, ed. F. R. Hartley, Wiley, New York, 1989, pp. 191–254;; W. Levason, ibid., pp. 567–641; W. L. Wilson, J. H. Nelson and N. W. Alcock, Organometallics, 1990, 9, 1699; A. Bader and F. Lindner, Coord. Chem. Rev., 1991, 108, 27 Search PubMed.
  3. C. A. McAuliffe, Phosphorus, Arsenic, Antimony and Bismuth Ligands, in Comprehensive Coordination Chemistry, eds. G. Wilkinson, R. D. Gillard and J. A. McCleverty, Pergamon, Oxford, UK, 1987, vol. 2, p. 989 Search PubMed; W. Levason, The Chemistry of Organophosphorus Compounds, eds. F. R. Hartley and S. Patai, Wiley, New York, 1990, vol. 1, p. 617 Search PubMed; F. A. Cotton and B. Hong, Prog. Inorg. Chem., 1992, 40, 179 Search PubMed; H. A. Mayer and W. C. Kaska, Chem. Rev., 1994, 94, 1239 Search PubMed.
  4. P. K. Byers, A. J. Canty and R. T. Honeyman, Adv. Organomet. Chem., 1992, 34, 1 CAS.
  5. J. Fernández-Baeza, F. A. Jalón, A. Otero and M. E. Rodrigo-Blanco, J. Chem. Soc., Dalton Trans., 1995, 1015 RSC.
  6. M. Fajardo, A. de la Hoz, E. Díez-Barra, F. A. Jalón, A. Otero, A. Rodriguez, J. Tejeda, D. Belleti, M. Lanfranchi and M. A. Pellinghelli, J. Chem. Soc., Dalton Trans., 1993, 1935 RSC.
  7. F. A. Jalón, B. R. Manzano, A. Otero and M. C. Rodriguez-Pérez, J. Organomet. Chem., 1995, 494, 179 CrossRef CAS.
  8. F. A. Cotton, L. R. Falvello and R. C. Najjar, Inorg. Chem., 1983, 22, 375 CrossRef CAS.
  9. J. Sandström, Dynamic NMR Spectroscopy, Academic Press, New York, 1982 Search PubMed.
  10. See, J. L. Templeton, Adv. Organomet. Chem., 1989, 29, 1 Search PubMed.
  11. K. Nakamoto, Infrared and Raman Spectra of Inorganic and Coordination Compounds, Wiley-VCH, New York, 1997 Search PubMed.
  12. See, for example: W. Lesueur, E. Solari, C. Floriani, A. Chiesi-Villa and C. Rizzoli, Inorg. Chem., 1997, 36, 3354 Search PubMed.
  13. E. J. Roskamp and S. F. Pedersen, J. Am. Chem. Soc., 1987, 109, 6551 CrossRef CAS.
  14. J. Tsuji, Organic Synthesis with Palladium Compounds, Springer, Berlin, 1980, vol. 10, pp. 2–3 Search PubMed.
  15. E. Díez-Barra, A. de la Hoz, A. Sánchez-Migallón and J. Tejeda, Heterocycles, 1992, 34, 1365 CAS.
  16. A. C. T. North, D. C. Phillips and F. S. Mathews, Acta Crystallogr., Sect. A, 1968, 24, 351 CrossRef.
  17. A. Altomare, G. Cascarano, C. Giacovazzo, A. Guagliardi, M. C. Burla, G. Polidori and M. Camalli, J. Appl. Crystallogr., 1994, 435 CrossRef.
  18. G. M. Sheldrick, Program for the Refinement of Crystal Structures from Diffraction data, University of Göttingen, Göttingen, 1993.
Click here to see how this site uses Cookies. View our privacy policy here.