Synthesis, Characterisation and Properties of Diazoketiminato-Chelate Complexes of Os(II)

Reactions of 2-(arylazo)aniline, L-NH2 [L-NH2 = p-RC6H4N=NC6H4NH2; where R=H for L1-NH2, CH3 for L2-NH2 and Cl for L3-NH2] with [Os(H)Br(CO)(PPh3)3] gave the complexes [OsBr(L-NH)(CO)(PPh3)2] for which cyclic volatammograms exhibited one quasi-reversible oxidative response within the range 0.54-0.6 V vs SCE. The X-ray crystal structure of [OsBr(L1-NH)(CO)(PPh3)2] has been determined and its electronic structure was evaluated on the basis of single point DFT calculations using its crystallographic coordinates.