Iridium organometallic complexes

The highest efficiency red emitters belong to the class of phosphorescent materials and are based on iridium organometallic complexes. The best performance achieved in guest-host systems, for example using a carbazole host and an Ir emitter (Ir(piq-F)2acac, has a maximum power efficiency and luminescent efficiency up to 4.73 lm/W and 13.7 cd/A, respectively. An EQE of 6.7% at 20 mA/cm2 with CIE (0.61, 0.36) has been demonstrated (Scheme 3.96) [361]. 

The first meaningful application of fluorescent iridium organometallic complexes in cell imaging was published by Lo and coworkers in 2008 [112,117]. The two fluorinated cationic iridium(lll) complexes 27 and 28 (Scheme 11.7), which exhibit bright green and red emissions, respectively, proved to be phosphorescent... 

The development of phosphorescent iridium organometallic complexes was another major breakthrough [8]. Such iridium complexes are triplet emitters and enhance the theoretical quantum efficiency of OLEDs from 25% for fluorescent... 

Sortais J-B, Pannetier N, Holuigue A, Barloy L, Sirlin C, Pfeffer M, Kyritsakas N (2007) Cyclometalation of primary benzyl amines by ruthenium(II), rhodium(III), and iridium(III) complexes. Organometallics 26 1856-1867... 

Numerous studies aimed at the understanding of the mechanism of these processes rapidly appeared. In this context, Murai examined the behavior of acyclic linear dienyne systems in order to trap any carbenoid intermediate by a pendant olefin (Scheme 82).302 A remarkable tetracyclic assembly took place and gave the unprecedented tetracyclo[6.4.0.0]-undecane derivatives as single diastereomer, such as 321 in Scheme 82. This transformation proved to be relatively general as shown by the variation of the starting materials. The reaction can be catalyzed by different organometallic complexes of the group 8-10 elements (ruthenium, rhodium, iridium, and platinum). Formally, this reaction involves two cyclopropanations as if both carbon atoms of the alkyne moiety have acted as carbenes, which results in the formation of four carbon-carbon bonds. 

Nagata, T., Pohl, M., Weiner, H., and Finke, R.G., Polyoxoanion-supported organometallic complexes carbonyls of Rhenium(I), Iridium(I), and Rhodium(I) that are soluble analogs of solid-oxide-supported M(CO) + and that exhibit novel M(CO)n+ mobility, Inorg. Chem., 36, 1366, 1997. 

Dihydrido Iridium Triisopropylphosphine Complexes From Organometallic Chemistry to Catalysis... 

The activation of methane in solution by an organometallic complex presents some experimental difficulties because any solvent that is likely to be chosen will be more reactive than methane. In addition, insolubility of the complex in liquid methane may preclude reaction with the pure hydrocarbon. These problems were overcome in the case of the reaction of CH4 with the iridium complex of Eq. 15.106 by taking advantage of the fact that the desired hydndo methyl complex Is thermodynamically more stable than other hydrido alkyl complexes. The methyl complex was produced by first creating a hydrido cyclohexyl complex and then allowing it to react with methane, m... 

Exploitation of Luminescent Organometallic Rhenium(I) and Iridium(III) Complexes in Biological Studies... 

Hydride Complexes of the Transition Metals Iridium Organometallic Chemistry Luminescence Macrocyclic Ligands Rhodium Inorganic Coordination Chemistry. 

This review of some aspects of the organometallic chemistry of iridium is certainly not exhanstive. There have been some types of complexes that have receive little notice such as those containing polyolefmic hgands and related compounds. Also, there are other organic transformations that may be catalyzed by iridium complexes. However, throughout this chapter the reader has been directed to a number of primary references as well as a number of review articles that will delve into some areas of iridium organometallic chemistry more deeply. 

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