Chemical Science p. 2633 - 2642 (2019)
Update date:2022-08-11
Topics:
Rocchigiani, Luca
Budzelaar, Peter H. M.
Bochmann, Manfred
The coordinatively unsaturated gold(iii) chelate complex [(C^N-CH)Au(C6F5)]+ (1+) reacts with main group hydrides H-BPin and H-SiEt3 in dichloromethane solution at -70 °C to form the corresponding σ-complexes, which were spectroscopically characterized (C^N-CH = 2-(C6H3But)-6-(C6H4But)pyridine anion; Pin = OCMe2CMe2O). In the presence of an external base such as diethyl ether, heterolytic cleavage of the silane H-Si bond leads to the gold hydrides [{(C^N-CH)AuC6F5}2(μ-H)]+ (2+) and (C^N-CH)AuH(C6F5) (5), together with spectroscopically detected [Et3Si-OEt2]+. The activation of dihydrogen also involves heterolytic H-H bond cleavage but requires a higher temperature (-20 °C). H2 activation proceeds in two mechanistically distinct steps: the first leading to 2 plus [H(OEt2)2]+, the second to protonation of one of the C^N pyridine ligands and reductive elimination of C6F5H. By comparison, formation of gold hydrides by cleavage of suitably activated C-H bonds is very much more facile; e.g. the reaction of 1·OEt2 with Hantzsch ester is essentially instantaneous and quantitative at -30 °C. This is the first experimental observation of species involved in the initial steps of gold catalyzed hydroboration, hydrosilylation and hydrogenation and the first demonstration of the ability of organic C-H bonds to act as hydride donors towards gold.
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Doi:10.1039/b902079a
(2009)Doi:10.1021/ja00764a042
(1972)Doi:10.1002/anie.201308377
(2014)Doi:10.1021/ic201545a
(2011)Doi:10.1021/tx9901231
(1999)Doi:10.1002/cber.19671000718
(1967)