Synthesis of ?4:?2-Exocyclic-Diene Iridium(I) Complexes Derived from 1,3-Oxazolidin-2-ones and Their Transformation into Iridium(III) Derivatives by Reaction with a Phosphine and with Aldehydes

The reaction of the dimer [Ir(?-Cl)(coe)2]2 with two exocyclic dienes like N-substituted 4,5-dimethylene-2-oxazolidinones a and b, and KTpMe2 yields derivatives of the composition TpMe2Ir(a or b) (1a,b). Derivative 1a reacts with Ph2PCCPPh2, with the formal oxidative addition of the diene moiety to the metal center and coordination of the phosphine in the ?1 mode. Derivatives 1a,b react with aromatic aldehydes to form the new compounds 3 (with benzaldehyde) and 4 (anisaldehyde), which contain an elaborated bidentate ligand formed by coupling of the two organic fragments (diene and aldehyde). The structures of compounds 3a,b have been determined by X-ray diffraction analysis.