Iridium complexes preparation

Iridium-catalyzed transfer hydrogenation of aldehyde 73 in the presence of 1,1-dimethylallene promotes tert-prenylation [64] to form the secondary neopentyl alcohol 74. In this process, isopropanol serves as the hydrogen donor, and the isolated iridium complex prepared from [Ir(cod)Cl]2, allyl acetate, m-nitrobenzoic acid, and (S)-SEGPHOS is used as catalyst. Complete levels of catalyst-directed diastereoselectivity are observed. Exposure of neopentyl alcohol 74 to acetic anhydride followed by ozonolysis provides p-acetoxy aldehyde 75. Reductive coupling of aldehyde 75 with allyl acetate under transfer hydrogenation conditions results in the formation of homoallylic alcohol 76. As the stereochemistry of this addition is irrelevant, an achiral iridium complex derived from [Ir(cod)Cl]2, allyl acetate, m-nitrobenzoic acid, and BIPHEP was employed as catalyst (Scheme 5.9). 

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

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,... 

Dihapto 7>ligands, in copper complexes, 2, 174 Dihydride iridium complexes, preparation, 7, 396 Dihydrido clusters, with decarutheniums, 6, 1036 Dihydrobenzofuran, carbene C-H insertions, 10, 193 Dihydrobenzopyran, carbene C-H insertions, 10, 193 ring-closing diene metathesis,... 

Dimethylimidazolium cation, in ionic liquids, 1, 855 Dimethyl iridium complexes, preparation, 7, 306 l-A -Dimethylnaphthylamines, in cobalt(III) complexes,... 

Monohydride iridium complexes, preparation and characteristics, 7, 395 Monohydrides... 

Polymetallic alkynes, with platinum heterobimetallic derivatives, 8, 647 homobimetallic complexes, 8, 645 polymetallic derivatives, 8, 648 Polymetallic cyclopentadienyl iridium complexes, preparation and characteristics, 7, 370... 

After screening various catalysts, a chiral iridium complex prepared in situ from [IrCl(cod)]2 (10 mol%) and Me-Duphos [1,2-bis (2,5-dimetilphospholano)benzene] was selected for the study of the [2+2+2] cycloaddition reaction (Table 2.3). Excellent diastereoselectiv-ity and enantioselectivity were achieved [59]. The oxygen-, nitrogen- or... 

Isomerization of [(, )-3-alkoxy-l-propenyl]boronates to the corresponding 7-alkoxyallylboronates was catalyzed by ruthenium or iridium complexes.64 [IrH2(TFlF)2(PPh2Me)2]PF6 was the most efficient catalyst for selective preparation of (ftfy-alkoxyallylboronates (Scheme 37). 

The stereoselective isomerization of allyl silyl ethers to (E)- or (Z)-silyl enol ethers was carried out in the presence of a cationic iridium(i) catalyst. The complex, prepared in situ by treating [Ir(cod)2]PFf,/2PPi3 with hydrogen was... 

Pardey and coworkers have also reported activity for the iridium complexes, including c/s-[Ir(CO)2(py)2](PF6)135 and more recently,168 Ir4(CO)12, which was prepared earlier by Della Pergola et al.102 The conditions used were Pco = 1.9 atm T = 100 °C [Ir] = 10 x 10 3 mol/L. Again, the pressure of Pco was higher relative to the studies with Rh complexes. The data are reported in Table 42. As observed with other metal complexes, electronic and steric effects are apparent. The Ir4(CO)12 complex was also tested in 4-picoline and displayed a similar turnover rate of 12 mol PI2/mol [Ir] per day. 

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