REVIEW: SOME CONSIDERATIONS ABOUT COORDINATION COMPOUNDS WITH END-ON DINITROGEN

• Published in: Journal of coordination chemistry 2001-11, Vol.54 (3-4), p.427-440
• Main Authors: Poveda, Arnulfo, Perilla, Isabel C., Pérez, Carmen R.
• Format: Article
• Language: English
• Subjects: Dinitrogen compounds; Low oxidation states; transition metal compounds; π acceptor ligands
• ISSN: 0095-8972; 1029-0389
• DOI: 10.1080/00958970108022654

There have been several reviews on dinitrogen coordination compounds but no special attention has been paid to correlate the electron configuration of the metal ions with the main features of the ligands in order to establish an electron configuration-stability relationship. In this article we consider nearly 200 complexes with terminal dinitrogen to find common characteristics that lead to the synthesis of other stable dinitrogen compounds. This survey shows that for coordination number 6 there is a strong tendency for a d 6 configuration in the metals, with oxidation states between 1- and 2. On the basis of quantum chemistry, dinitrogen as a ligand can be compared with the isoelectronic species CO, CN − , NO + . The MO and orbital energy diagrams indicate that N 2 is not a good donor neither a good acceptor, but with the appropriate symmetry and in the presence of a good π-donor metal it forms an N 2 ← M π-bond strengthened by an N 2 → M σ-back-bonding.