Gold complexes mononuclear

Guzman, J. and Gates, B.C. (2003) Structure and reactivity of a mononuclear gold-complex catalyst supported on magnesium oxide. Angewandte Chemie International Edition, 42, 690-693. 

A mononuclear gold complex catalyst supported on MgO spectroscopic characterization during ethylene... 

Guzman, J. and B. C. Gates, Structure and Reactivity of a Mononuclear Gold-Complex Catalyst Supported on Magnesium Oxide , Angew. Chem. Int. Ed., vol 42, Issue 6, pp 690-3. 

Fig. 19.1 Structural model of the surface-bound mononuclear gold complex on y-Al203, based on IR, EXAFS, and XANES characterization. Reprinted with permission from [18]. Copyright 2003 American Chemical Society...

The above-mentioned mononuclear gold complex prepared on MgO formed from Au(CH3)2(acac) and represented on the basis of IR and EXAFS spectra as Au" (CH3)2 OMg 2 is the precursor of a catalyst for ethene hydrogenation [32] the rate of the catalytic reaction at 353 K and atmospheric pressure in the presence of a mixture of ethene, H and He (ethene partial pressure, P, 40 Torr , ... 

Guzman J, Gates BC (2004) A mononuclear gold complex catalyst supported on MgO Spectroscopic characterization during ethylene hydrogenation catalysis. J Catal 226 111... 

Thus, the abstraction of the chlorine atom in [Au(QF5)2Cl(dppm)j [175] provides a mononuclear gold(I II) derivative with the diphosphine acting as a chelate ligand, which is an excellent starting material in the synthesis of dinuclear or polynuclear methanide and methanidiide complexes after deprotonation of the dppm ligand (first deprotonation with HNa and the second with acetylacetonate gold(I) derivatives) [198-201] (Scheme 3.3)... 

Mononuclear gold(II) complexes, consistent with a d9 configuration, must be paramagnetic (Meff=1.79 MB) and show a hyperfine four-line EPR signal, in accordance with the nuclear spin of 197Au (1 = 3/2). These two properties are evidence of a real gold(II) complex in addition to their stoichiometry. 

Carbene complexes have also been prepared by transmetallation reactions. Lithiated azoles react with gold chloride compounds and after protonation or alkylation the corresponding dihydro-azol-ylidene compounds, e.g., (381) or (382), are obtained.22 9-2264 Silver salts of benz-imidazol have also been used to obtain carbene derivatives.2265 Mononuclear gold(I) carbene complexes also form when trimeric gold(I) imidazolyl reacts with ethyl chlorocarbonate or ethyl idodate.2266,2267 The treatment of gold halide complexes with 2-lithiated pyridine followed by protonation or alkylation also yields carbene complexes such as (383).2268 Some of these carbene complexes show luminescent properties.2269-2271... 

Oxazolinyl-thien-5-yl- and 2-oxazolinyl-thien-3-yl-lithium react with (tht)AuCl to produce the corresponding gold complexes as a dimer and a trimer, respectively. Mononuclear compounds are obtained with (tht)AuC6F5 and (Ph3P)AuCl (Scheme 68).269... 

The following section shows specific examples of association of dicoordinated mononuclear gold units which have been classified according to the nuclearity of the aggregate. Despite this general classification, the different polymorphic forms of a specific compound are discussed together, as well as the structures of complexes with small ligand variations. 

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