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The facile insertion of CO2 into iridium(I) hydroxide, alkoxide, and amide bonds was recently reported. In particular, [Ir(cod)(I iPr)(OH)] (I iPr=1,3-bis(isopropyl)imidazol-2-ylidene) reacted with CO2 in solution and in the solid state in a matter of minutes to give the novel [{Ir(cod)(I iPr)}2(μ-κ1 O:κ2 O, O-CO3)] complex. In the present study, this reaction is probed using kinetics and theoretical studies, which enabled us to analyse its facile nature and to fully elucidate the reaction mechanism with excellent correlation between the two methods. [ABSTRACT FROM AUTHOR]

Ammoniaborane dehydrogenation can be catalyzed by a number of organometallicspecies. [Ir(κ2-ItBu)2][PF6] (ItBu = 1,3-bis(tert-butyl)imidazol-2-ylidene) is the most active catalystfor this process that has been reported to date. We explore hereinthe absolute limits of the use of this and related complexes, including[Ir(κ2-ItBu)2][BArF4], [Ir(H)2(ItBu)2][BArF4], and[Ir(κ2-ItBu)2(NH3)][BArF4] (BArF4= tetrakis(3,5-bis(trifluoromethyl)phenyl)borate). [ABSTRACT FROM AUTHOR]

The reactivity of a number of IrI complexes towards CO2 is explored using [Ir(NHC)(OH)] as a key synthon. CO2 insertion into Ir–O and Ir–N bonds proved facile, yielding a number of IrI-carbonates and -carbamates. Most importantly, reaction between CO2 and IrI–OH led to isolation of the novel [{IrI}2-(μ-κ1:κ2-CO3)] complex. [ABSTRACT FROM AUTHOR]

The facile insertion of CO2 into iridium(I) hydroxide, alkoxide, and amide bonds was recently reported. In particular, [Ir(cod)(IiPr)(OH)] (IiPr = 1,3-bis(isopropyl)imidazol-2-ylidene) reacted with CO2 in solution and in the solid state in a matter of minutes to give the novel [{Ir(cod)(IiPr)}2(μ-κ(1)O:κ(2)O,O-CO3)] complex. In the present study, this reaction is probed using kinetics and theoretical studies, which enabled us to analyse its facile nature and to fully elucidate the reaction mechanism with excellent correlation between the two methods., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The iridium(I) hydroxide complex [Ir(OH)(COD)(I(i)Pr)] has been shown to be a competent catalyst for the rearrangement of allylic alcohols to ketones. Reactions proceed in short reaction times (1-1.5 h) with microwave heating, in the absence of additives.

The reactivity of a number of Ir(I) complexes towards CO2 is explored using [Ir(NHC)(OH)] as a key synthon. CO2 insertion into Ir-O and Ir-N bonds proved facile, yielding a number of Ir(I)-carbonates and -carbamates. Most importantly, reaction between CO2 and Ir(I)-OH led to isolation of the novel [{Ir(I)}2-(μ-κ(1):κ(2)-CO3)] complex.

A family of iridium(I) hydroxides of the form [Ir(cod)(NHC)(OH)] (cod = 1,5-cyclooctadiene, NHC = N-heterocyclic carbene) is reported. Single-crystal X-ray analyses and computational methods were used to explore the structural characteristics and steric properties of these new complexes. The model complex [Ir(cod)(IiPr)(OH)] (IiPr = 1,3-(diisopropyl)imidazol-2-ylidene) undergoes reaction with a wide variety of substrates including boronic acids and silicon compounds. In addition, O-H, N-H and C-H bond activation was achieved with alcohols, carboxylic acids, amines and various sp-, sp(2)- and sp(3)-hybridised carbon centres, giving access to a wide range of new Ir(I) complexes. These studies have allowed us to explore the exciting reactivity of this motif, revealing a versatile and useful synthon capable of activating important chemical bonds under mild (typically room temperature) conditions. No additives were required and, in the case of X-H bond activation, water was the only waste product, rendering this an atom efficient procedure for bond activation. This system has great potential for the construction of new catalytic cycles for organic synthesis and small-molecule activation., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Alkene hydrosilylation and dehydrogenative silylation reactions, mediated by [Rh(cod)(NHC)(OH)] complexes (cod = 1,5-cyclooctadiene; NHC = N-heterocyclic carbene) are described. The study details a comparison of the catalytic activity and steric characteristics of four rhodium complexes bearing different NHC ligands. The novel [Rh(cod)(Ii-PrMe)(OH)] complex (Ii-PrMe = 1,3-diisopropyl-4,5-dimethylimidazol-2-ylidine) was designed to improve the reactivity of Rh(I)-hydroxides and proved to be a successful promoter of hydrosilylation and dehydrogenative silylation, displaying good stereo- and regiocontrol.