Novel Iridaboranes from the Reactions of Cp*2Ir2HxCl4-x, x = 0−2, with LiBH4. Existence of a Concurrent Reaction Channel in the Conversion of Metal Chlorides to Metal Hydrides
摘要:
Reaction of either Cp*2Ir2Cl4 or Cp*2Ir2HCl3 with LiBH4 leads to formation of the new iridaborane Cp*Ir(H)(2)B3H7, 1 (a borallyl complex), in parallel with Cp*IrH4. In contrast, reaction, of Cp*2Ir2H2Cl2 with LiBH4 leads exclusively to Cp*Ir-2(2)(H)(3)B2H5, 3, which is isolobal with 1.
Mechanistic Investigations of the Iridium(III)-Catalyzed Aerobic Oxidation of Primary and Secondary Alcohols
作者:Bi Jiang、Yuee Feng、Elon A. Ison
DOI:10.1021/ja8049595
日期:2008.11.5
The commercially available catalysts [(Cp*IrCl2)(2)] is employed with O-2 as the terminal oxidant in the presence of catalytic amounts of Et3N for the aerobic oxidation of primary and secondary alcohols. A new mechanism for the Ir-catalyzed aerobic oxidation is also presented that suggests that the transition metal maintains its +3 oxidation state throughout the entire catalytic cycle.
Acid–Base Bifunction and Umpolung of the Bridging Hydride in a Coordinatively Unsaturated Mesylimido- and Hydrido-Bridged Diiridium Complex
The mono(mesylamido)-bridged diiridium(III) complex [(CP*IrCl)(2)(mu(2)-H)(mu(2)-NHMS)] (CP* = eta(5)-C-5(CH3)(5), MS = SO2CH3) undergoes reversible dehydrochlorination to afford the unsaturated imido-bridged dinuclear complex [Cp*Ir(mu H2-)(mu(2)-NMs)IrClCP*] (2) The reaction of 2 with trimethylphosphine gives the simple adduct [Cp*Ir[P(CH3)(3)}(mu(2)-H)(mu(2)-NMs)IrClCp*], while the reaction with CO results in sequential formation of the mono- and dicarbonyl Ir(II) complexs [Cp*Ir(CO)(mu(2)-NHMs)IrClCp*] and [Cp*Ir(CO)}(2)(mu(2)-NMs)] and with concomitant umpolung of the bridging hydrido ligand in 2 to the amido proton.