Reaction of N-(2'-hydroxyphenyl)pyrrole-2-aldimine (H2L) with [M(PPh3)3Cl] (M = Rh, Ir) affords complexes of type [M(PPh3)2(L)Cl]. Structures of both complexes have been determined by X-ray crystallography. In both complexes, the N-(2'- hydroxyphenyl)pyrrole-2-aldimine ligand is coordinated to the metal centre, via dissociation of the acidic protons, as a dianionic tridentate N,N,O-donor. The M(L)C1 fragment constitutes an equatorial plane with the metal at the centre and the two PPh3 ligands occupying axial positions. The complexes are diamagnetic (low-spin d6, S = 0) and show intense MLCT transitions in the visible region. Cyclic voltammetry of the [M(PPh3) 2(L)CI] complexes shows reversible M(III)-M(IV) oxidation near 0-5 V vs SCE and quasi-reversible ligand-centred oxidative response near 1.0 V vs SCE. © Indian Academy of Sciences.
|Number of pages||7|
|Journal||Journal of Chemical Sciences|
|Publication status||Published - Mar 2005|
- Crystal structure
- Rhodium and iridium complexes
- Spectral and electrochemical properties