Iridium polypyridine complexes

In the following sections, luminescent organometallic rhenium(I) and iridium(III) polypyridine complexes relying on the labelling or binding strategies mentioned above will be described. We focus on the molecular structures, spectroscopic and photophysical properties of the complexes, and the emissive behaviour and potential applications of the labelled bioconjugates. 

Iridium(lll) complexes, especially those with polypyridine ligands, as therapeutic and bioimaging reagents for cellular applications 12RCA12069. Isolation, biological activity and synthesis of the natural anticancer product eUipticine and related pyridocarbazoles 12RCA8883. 

Iridium complexes have recently been investigated as luminescent sensors able to monitor the variation of homocysteine and cysteine levels in cells (of significance to the physiological balance in biology), in this case using a cationic iridium(III) complex. Furthermore, zinc ion sensing in vitro was possible via a family of cyclometallated iridium(III) polypyridine compounds including a di-2-picolylamine. ... 

Luminescent cyclometallated iridium(III) polypyridine biotin complexes [Ir(NAC)2(bpy-CH2-NH-C2-NH-biotin)]+ (NAC = ppy, mppy, ppz, mppz, bzq, pq)... 

A related series of novel cyclometallated iridium(III) polypyridine thiourea complexes also display anion-induced luminescence quenching. The representative complex 89 was tested in acetonitrile solution with fluoride, acetate and dihydrogenphosphate, and gave logic values for the 1 1 complex of 3.38,... 

Professor A.P. Sadimenko of the University of Fort Hare, Repubhc of South Africa, has continued his series on organometallic complexes by summarizing the organometallic complexes formed by metals of the cobalt (cobalt, rhodium, iridium) and nickel (nickel, palladium, platinum) groups with polypyridines. This is the first summary of the numerous organic complexes that these metals form with polypyridines. 

Luminescent organometallic complexes used for cell imaging can be divided in two main families, namely (i) carbonyl complexes, most commonly octahedral rhenium c-tricarbonyl derivatives incorporating a polypyridine ligand and (ii) cyclometalated complexes such as iridium and platinum derivatives containing the ubiquitous 2-phenylpyridine unit (complexes 1-3 in Scheme 11.2). 

More recently, systems based on polypyridine coordination compounds of ruthenium(II) [46-49], rhodium(I) [50a] and iridium(I) [50] have been shown to efficiently catalyse the thermal WGSR. An important effect of the substituent ortho to the nitrogen atom of the ligand has been demonstrated in the case of Ir(I) leading to one of the most efficient catalysts known today [50b]. [Ru(bpy)2(CO)Cl] has also been studied and all of the possible intermediates within the catalytic cycle (hydrocarbonyl complex, metal hydride, aquo species) have been isolated and characterized [48]. 

---