Strong intramolecular π–π interactions favor the formation of 2:1 (L:M) lanthanide complexes of tris(2-benzimidazolylmethyl)amine

Abstract

Reaction of the tripodal ligand tris(2-benzimidazolylmethyl)amine with lanthanides(III) in the presence of counterions ClO₄^–, OTf^– or Cl^– results, even for ligand to metal ratios lower than 2, in the formation of bisligand complexes showing strong p–p interactions between the benzimidazole rings both in solution and in the solid state.

References

1. N. Sabbatini, M. Guardigli and J.-M. Lehn, Coord. Chem. Rev., 1993, 123, 201.
2. G. H. Frost, F. A. Hart, C. Heath and M. B. Hursthouse, Chem. Commun., 1969, 1421.
3. C. Piguet, A. F. Williams, G. Bernardinelli and J.-C. G. Bünzli, Inorg. Chem., 1993, 32, 4139.
4. S. Petoud, J.-C. G. Bünzli, F. Renaud, C. Piguet, K. J. Schenk and G. Hopfgartner, Inorg. Chem., 1997, 36, 5750.
5. R. Wietzke, M. Mazzanti, J.-M. Latour, J. Pecaut, P.-Y. Cordier and C. Madic, Inorg. Chem., 1998, 37, 6690.
6. R. Wietzke, M. Mazzanti, J.-M. Latour and J. Pecaut, unpublished results.
7. W. D. Horrocks, Jr. and D. R. Sudnick, Acc. Chem. Res., 1981, 14, 384.
8. E. C. Constable and M. D. Ward, J. Am. Chem. Soc., 1990, 112, 1256.
9. C.-Y. Su, B.-S. Kang, H.-Q. Liu, Q.-G. Wang and T. C. W. Mak, Chem. Commun., 1998, 1551.
10. P. Caravan, T. Hedlund, S. Liu, S. Sjöberg and C. Orvig, J. Am. Chem. Soc., 1995, 117, 11 230.
11. M. P. Lowe, P. Caravan, S. J. Rettig and C. Orvig, Inorg. Chem., 1998, 37, 1637.
12. J. H. Forsberg, Coord. Chem. Rev., 1973, 10, 195.