Iridium complexes applications

Md.K. Nazeeruddin, R. Humphry-Baker, D. Berner, S. Rivier, L. Zuppiroli, and M. Graetzel, Highly phosphorescence iridium complexes and their application in organic light-emitting devices, J. Am. Chem. Soc., 125 8790-8797 (2003). 

We, the editors, believe that organoiridium chemistry has not only a rich past, but that the application of iridium complexes in organic transformations also has a brilliant future ... 

Fig. 2.10 Applications of asymmetric hydroboration with diphosphine catalysts to meso-symmetric alkenes. For 10(a), iridium complexes reverse the sense of enantioselectivity in up to 54% enantiomeric excess.

SYNTHESIS AND APPLICATION OF PHOSPHINITE OXAZOLINE IRIDIUM COMPLEXES FOR THE ASYMMETRIC HYDROGENATION OF ALKENES... 

The complex [mer-IrH2Cl(PMe3)3] was used as a catalyst for the hydrogenation of alkynes and alkenes in water, and water-soluble ethylenediamine (en) complexes of iridium, [Ir(COD)(en)]Cl, were found to be excellent catalysts for aqueous hydrogenations (94). It would be interesting to determine the loss of iridium during application of these complexes in biphasic catalysis. 

A cationic iridium complex (71), related to those discussed in Section I V,H, was obtained from [Ir(j/5-CsMes)(Me2CO)3], (PF6)2, and mesityl oxide. If this or the original starting material is heated in solution in acetone, it is converted to the hydroxypentadienyl cation (72) (228). These synthetic procedures have not found general application. The results suggest, however, that oxapentadienyl complexes might repay further investigation. 

Application of Iridium Complexes in Organic Light Emitting Devices... 

In an important report, Janowicz and Bergman have described the photochemical incorporation of an alkyl group from an alkane into an iridium complex. The process does not appear to involve alkyl radicals, but is thought to occur via two successive concerted steps. This report may point the way to new catalytic processes for the functionalization of alkanes. The photoaddition of alkyl halides to alkenes catalysed by Cu complexes represents a novel process for formation of C-C bonds, and may have useful synthetic applications (Mitani et ai). The possibility of analogous intramolecular reactions comes readily to mind. 

BINAP complexes have been used extensively in asymmetric synthesis, for example in hydrogenations,389,390 olefin isomerizations,390 arylation of olefins,391 and enantioselective allylation of aldehydes.392 Palladium or platinum complexes of (165) find important applications in enantioselective C—C bond formation,393-396 whilst iridium complexes are catalysts for the hydrogenation of nonfunctionalized tri- and tetrasubstituted olefins. 97... 

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