A new route to tris(pyrazolyl)borate ligands and new structural variations in TlTp complexes †

Abstract

Tris(pyrazolyl)borate ligands were synthesized by a new route from MeBBr₂ and pyrazole derivatives under very mild conditions at room temperature to give TlL complexes. For L = [MeB(3,5-Me₂pz)₃]^– a bridging co-ordination of the ligand is found, interpreted as sterically enforced upon comparison with the structures for L = [MeB(3-Mepz)₃]^– and [HB(3,5-Me₂pz)₃]^–.

References

1. S. Trofimenko, Chem. Rev., 1993, 93, 943; P. K. Byers, A. J. Canty and R. T. Honeyman, Adv. Organomet. Chem., 1992, 34, 1; N. Kitajima and W. B. Tolman, Prog. Inorg. Chem., 1995, 43, 419; G. Parkin, Adv. Inorg. Chem., 1995, 42, 291; D. L. Reger, Coord. Chem. Rev., 1996, 147, 571; M. Etienne, Coord. Chem. Rev., 1997, 156, 201.
2. S. Trofimenko, Inorg. Synth., 1970, 99, 12.
3. C. Janiak and L. Esser, Z. Naturforsch., Teil B, 1993, 48, 394.
4. S. Trofimenko, J. Am. Chem. Soc., 1967, 89, 6288.
5. D. L. White and J. W. Faller, J. Am. Chem. Soc., 1982, 104, 1548; D. L. Reger and M. E. Tarquini, Inorg. Chem., 1982, 21, 840.
6. F. Jäkle, K. Polborn and M. Wagner, Chem. Ber., 1996, 129, 603; F. F. de Biani, F. Jäkle, M. Spiegler, M. Wagner and P. Zanello, Inorg. Chem., 1997, 36, 2103.
7. T. E. Cole, R. Quinanilla, B. M. Smith and D. Hurst, Tetrahedron Lett., 1992, 33, 2761.
8. C. Janiak, Main Group Met. Chem., 1997, 21, 33; Coord. Chem. Rev., 1997, 163, 107.
9. C. Janiak, J. Prakt. Chem., 1998, 340, 181.
10. A. L. Rheingold, L. M. Liable-Sands and S. Trofimenko, Chem. Commun., 1997, 1691.
11. C. Janiak and R. Homann, J. Am. Chem. Soc., 1990, 112, 5924.
12. G. Ferguson, M. C. Jennings, F. J. Lalor and C. Shanahan, Acta Crystallogr., Sect. C, 1991, 47, 2079.
13. S. Trofimenko, University of Delaware, personal communication, October 1998.
14. C. Janiak, S. Temizdemir and T. G. Scharmann, Z. Anorg. Allg. Chem., 1998, 624, 755.
15. A. Looney, R. Han, I. B. Gorrell, M. Cornebise, K. Yoon, G. Parkin and A. L. Rheingold, Organometallics, 1995, 14, 274; D. L. Reger, S. S. Mason and A. L. Rheingold, J. Am. Chem. Soc., 1993, 115, 10406; D. L. Reger and S. S. Mason, Organometallics, 1993, 12, 2600.
16. G. M. Sheldrick, SHELXS 97, SHELXL 97, Programs for Crystal Structure Analysis, University of Göttingen, 1997.
17. M. N. Burnett and C. K. Johnson, ORTEP III, Oak Ridge Thermal Ellipsoid Plot Program for Crystal Structure Illustrations, Report ORNL-6895, Oak Ridge National Laboratory, Oak Ridge, TN, 1996; L. J. Farrugia, ORTEP 3, windows version 1.0.4β, J. Appl. Crystallogr., 1997, 30, 565.