SYNTHESIS AND CHARACTERIZATION OF NEW TRINUCLEAR Rh (I)-IMIDAZOLATE COMPLEXES

In connection with biologically active molecules such as iron-heme and vitamin B, numerous transition metal complexes containing neutral imidazole molecules as a ligand have been synthesized and characterized.!) On the other hand, such complexes having imidazolate anions instead, have been less studied; some of recent examples include the Fe (II) ,z)Cu (II) ,3) Ni (II) ,4) Ir (II) ,5) and Cr (IlI) 6) systems. Previously, two of the present authors reported in a Japanese patent/) the preparation of several kinds of trinuclear Rh (I) complexes having imidazolate as an anionic ligand; the first successful synthesis of this type of Rh (1) complexes to our knowledge. Later, Tripicchio et al. prepared imidazolate-Rh (1) and Ir (I) complexes and found that the complexes having diolefins as a ligand exists mainly in a trinuclear complex, while those having dicarbonyl compounds as a ligand does in a tetranucleous form.) The purpose of the present paper is to give the full details of our earlier report.