Iridium trifluoromethyl derivatives

Chen and coworkers have developed two new phosphorescent blue emitters, which have two identical 2-(2,4-difluorophenyl)pyridine ligands and are derivatives of the Firpic compound, iridium(III) bis(4,6-difluorophenylpyridinato)-3-(trifluoromethyl)-5-(pyridin-2-yl)-1, 2,4-triazolate (Firtaz) and iridium(III) bis(4,6-difluorophenylpyridinato)-5-(pyridin-2-yl)-l//-tetrazolate (FirN4) (Scheme 3.90) [314]. Both these two blue emitters show a 10-nm blue-shift of the emission compared with Firpic. Unfortunately, the efficiency of such blue emitters is inferior to those of Firpic and Fir6. There is no lifetime data reported for such devices. 

In order to explain reactions of diazomethane and its derivatives with coordination compounds, it has been proposed that the formation of intermediate carbene complexes takes place. In the reaction of bis(trifluoromethyl)diazomethane with [IrCl(CO)(PMePh2)2] the carbene complex [IrCl(CO)(PMePh2)2 C(CF3)2 ] is formed rather than the chlorobis(trifluoromethyl)methyl iridium complex Ir CCl(CF3)2 (CO)(PMePh2)2. In many cases, such complexes were isolated and investigated ... 

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