The fixation and reduction of dinitrogen using lanthanides: praseodymium and neodymium meso-octaethylporphyrinogen–dinitrogen complexes

Abstract

The meso-octaethylporphyrinogen–sodium–lanthanide complexes, [{(η⁵ : η¹ : η⁵ : η¹-Et₈N₄)M}Na(thf)₂], in the presence of Na metal and under a nitrogen atmosphere, fix and reduce dinitrogen to the [N₂]^2– anion, as shown by the isolation of the dinuclear complexes containing the [M(µ-η² : η²-N₂)M] moiety [M = Pr, Nd].

References

1. D. Jacoby, C. Floriani, A. Chiesi-Villa and C. Rizzoli, J. Chem. Soc., Chem. Commun., 1991, 790; J. Am. Chem. Soc., 1993, 115, 3595; D. Jacoby, S. Isoz, C. Floriani, A. Chiesi-Villa and C. Rizzoli, J. Am. Chem. Soc., 1995, 117, 2793; C. Floriani, in Stereoselective Reactions of Metal-Activated Molecules, ed. H. Werner and J. Sundermeyer, Vieweg, Wiesbaden, 1995, pp. 97–106; S. De Angelis, E. Solari, A. Chiesi-Villa and C. Rizzoli, Organometallics, 1995, 14, 4505; D. Jacoby, S. Isoz, C. Floriani, K. Schenk, A. Chiesi-Villa and C. Rizzoli, Organometallics, 1995, 14, 4816; S. Isoz, C. Floriani, K. Schenk, A. Chiesi-Villa and C. Rizzoli, Organometallics, 1996, 15, 337; G. Solari, E. Solari, A. Chiesi-Villa and C. Rizzoli, Organometallics, 1997, 16, 508.
2. C. Floriani, Pure Appl. Chem., 1996, 68, 1.
3. S. De Angelis, E. Solari, A. Chiesi-Villa and C. Rizzoli, J. Am. Chem. Soc., 1994, 116, 5691; J. Am. Chem. Soc., 1994, 116, 5702; C. Floriani, Chem. Commun., 1996, 1257.
4. Two reports appeared on Sm–N₂ chemistry, the first one (a) containing a true N₂ bridging two samarium ions, the second one (b) containing the Li₄N₂ unit within two samarium ions: (a) W. J. Evans, T. A. Ulibarri and J. W. Ziller, J. Am. Chem. Soc., 1988, 110, 6877; (b) J. Jubb and S. Gambarotta, J. Am. Chem. Soc., 1994, 116, 4477.
5. The unusual µ-η² : η² bonding mode has been found also in a U(III) derivative: P. Roussel and P. Scott, J. Am. Chem. Soc., 1998, 120, 1070.
6. R. Ferguson, E. Solari, C. Floriani, D. Osella, M. Ravera, N. Re, A. Chiesi-Villa and C. Rizzoli, J. Am. Chem. Soc., 1997, 119, 10104 and references therein; C. E. Laplaza, M. J. A. Johnson, J. C. Peters, A. L. Odom, E. Kim, C. C. Cummins, G. N. George and I. J. Pickering, J. Am. Chem. Soc., 1996, 118, 8623 and references therein; A. Zanotti-Gerosa, E. Solari, L. Giannini, C. Floriani, A. Chiesi-Villa and C. Rizzoli, J. Am. Chem. Soc., 1998, 120, 437.
7. M. F. Lappert, P. P. Power, A. R. Sanger and R. C. Srivastava, Metal and Metalloid Amides. Synthesis, Structures and Physical Properties, Ellis Horwood, Chichester, UK, 1980, ch. 8.