Dinuclear iridium complexes

Amido-bridged dinuclear iridium complexes, preparation,... 

Another interesting feature of the dinuclear iridium complex [IrCl(PF3)2]2 is its very dark color and metallic luster in the solid state, indicative of intermetallic bonding. A recent single-crystal structure determination (149) reveals that the structure consists of infinite zigzag chains of iridium atoms with short inter- and intramolecular Ir Ir contacts (see Figs. 15 and 16). 

Several reports have dealt with the 3,6-bis(2-pyridyl)-l,2,4,5-tetrazine (bptz) ligand reactions of bptz with first-row transition metals have been explored <05JA12909> the synthesis and crystallographic study of a dinuclear iridium complex have been published <051CA1317> and a new molecular propeller compoimd prepared from the reaction of bptz with Ag[AsFe] has been reported <05CC46>. 

Martin, M. Sola, E. Tejero, S. Lopez, J. A. Oro, L. A. Mechanistic investigations of imine hydrogenation catalyzed by dinuclear iridium complexes. 

The dinuclear iridium(l) diphosphine complexes 42 can also activate carboxylic acids easily. For example, the reaction of [IrCl(binap)]2 (42b) with an excess of acetic acid or benzoic acid in toluene at room temperature gave the corresponding (hydri-... 

The most fundamental reaction is the alkylation of benzene with ethene.38,38a-38c Arylation of inactivated alkenes with inactivated arenes proceeds with the aid of a binuclear Ir(m) catalyst, [Ir(/x-acac-0,0,C3)(acac-0,0)(acac-C3)]2, to afford anti-Markovnikov hydroarylation products (Equation (33)). The iridium-catalyzed reaction of benzene with ethene at 180 °G for 3 h gives ethylbenzene (TN = 455, TOF = 0.0421 s 1). The reaction of benzene with propene leads to the formation of /z-propylbenzene and isopropylbenzene in 61% and 39% selectivities (TN = 13, TOF = 0.0110s-1). The catalytic reaction of the dinuclear Ir complex is shown to proceed via the formation of a mononuclear bis-acac-0,0 phenyl-Ir(m) species.388 The interesting aspect is the lack of /3-hydride elimination from the aryliridium intermediates giving the olefinic products. The reaction of substituted arenes with olefins provides a mixture of regioisomers. For example, the reaction of toluene with ethene affords m- and />-isomers in 63% and 37% selectivity, respectively. 

Iridium(O).—The first dinuclear trifluorophosphine complex of Ir has been prepared by elimination of H from IrH(PF3)4 ... 

Ferrocenoylamino acids have been converted into 2-ferrocenyl-5(477)-oxazo-lones 348 and 350 that act as N donors in palladium, platinum, and iridium complexes. Reaction of 348 with chloro-bridged palladium(II) and platinum(II) complexes affords a series of N-coordinated oxazolone complexes 349. Reaction of the unsubstituted 2-ferrocenyl-5(477)-oxazolone 350 with the chloro-bridged iridium(III) complex [(ri -C5Me5)IrCl2]2 produces a dinuclear complex 351, analogous to that obtained from 2-phenyl-5(477)-oxazolone (Scheme 7.113)." ° ... 

Bis[iV,iV -di(2-pyridyl)-imidazol-2-ylidene]aurate(I) tetrafluoroborates, preparation, 2, 292-293 Bis[iV,iV -di(2-pyridyl-methyl)-imidazol-2-ylidene]aurate(I) tetrafluoroborates, preparation, 2, 292-293 Bis(diselenolate) complexes, dinuclear iron compounds, 6, 242 Bis(dithiolene) compounds, in tungsten carbonyl and isocyanide complexes, 5, 644 Bis(enolato) complexes, with bis-Cp Ti(IV), 4, 589 Bis(enones), in reductive cyclizations, 10, 502 Bis(ethanethiolato) complexes, with bis-Cp Ti(IV), 4, 601 Bis(ethene)iridium complexes, preparation, 7, 328-329 -Bis(fluorenyl)zirconocene dichlorides, preparation,... 

Dinuclear iridium alkynyl complexes, synthesis and characteristics, 7, 331... 

The ligands triphos or/ and np in presence of compounds of iron, cobalt, nickel, rhodium, iridium and palladium, by reaction with THF solutions of white phosphorus, P, or yellow arsenic, As, form mononuclear or dinuclear sandwich complexes containing the cyclo-triphosphorus or cyclo-triarsenic units which behave as 3n-electrons rings. 

The hydroxide ion is a well-established bridging ligand, and hydroxo-bridged complexes of iridium(III) have been reviewed. Among the dinuclear iridium(I) complexes that have structures supported by 0H ligands is [Cp Ir(/u.-0H)3lrCp ]+, and closely related to this is (cod)Ir(/u.-OPh)2lr(cod). The presence of the three OH... 

In 2006, Genet and Mashima developed a new and convenient one pot reaction to prepare mononuclear halide carboxylate iridium(III) complexes and cationic triply halogen bridged dinuclear iridium(III) complexes of BINAP, p TolBINAP, and SynPhos. These iridium(III) complexes were tested as catalyst precursors for asymmetric hydrogenation of 2 phenylquinoline (Scheme 10.8) [10]. Cationic iododi nuclear p TolBINAP (S) L6e and SynPhos (S) L3c complexes had better enantios... 

Similar to other d -d systems, the dinuclear iridium(I) complex [Ir(/u,-pz)(COD)]2 (23) showed spin-allowed and spin-forbidden (da — pa) absorption bands at 498 and 585 nm, respectively. Under ambient conditions, the complex displayed fluorescence at 564 nm and phosphorescence at 687 nm, which were assigned to singlet and triplet excited states of (da — pa) character. The triplet excited state of the complex was a powerful reductant with an excited-state reduction potential E° (Ir2+ ) of —1.81V vs. SSCE. Facile electron transfer reactions occurred between the excited complex and methyl viologen and other pyridinium acceptors. The absence of an inverted effect for the forward electron transfer reactions, and the presence of such inverted behavior for the back-electron-transfer reactions were observed and explained. ... 

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