Gold complexes reactivity

Multinuclear (isocyanide)gold complexes, reactivity, 2, 287 Multi-phase organometallic catalysis, in ionic liquids, 1, 856 Multiple-quantum MAS, half-integer spin quadrupolar nuclei central transition NMR studies, 1, 466 Multistate magnetization transfer, in dynamic NMR magnetization, 1, 410 Multistep catalytic cycles... 

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. 

The effect of the alkyl group, R, on the rate of reaction (42) in solvent dioxan may be seen from Table 34. Relative rate coefficients are given in Table 35, and show that for all the mercuric salts used, the order of reactivity of the gold complexes is that of increasing electron release by the group R, viz. 

C-H activation has been extended to a number of other methyl ketones MeC(0)R64 and the reactivity of ketonyl gold complexes has been explored in some... 

Mono(A, A -diorganyl-imidazol-2-ylidene)gold(I) complex, reactivity, 2, 293... 

An interesting transformation involving the indole nucleus was found from propargylic carboxylates to give tetracychc compounds with Au(I) (equation 85). This reaction proceeds by an allene-gold complex in equilibrium with the aUcenyl-gold species, which reacts intramolecularly with the indole to form the product. When the reaction of these substrates is performed with dichloro(pyridine-2-carboxylato)gold(III) or Pt(II) as catalysts, products in equation (86) are obtained instead. This new reactivity can be explained by a formal [3 + 2] cycloaddition of 1,3-dipole... 

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. 

Guzman J, Anderson BG, Vinod CP, Ramesh K, Niemantsverdriet JW, Gates BC (2005) Synthesis and reactivity of dimethyl gold complexes supported on MgO Characterization by infrared and X-ray absorption spectroscopies. Langmuir 21 3675... 

Gold complexes, and more especially gold(I) complexes, are by far the most employed catalytic systems. The presence of one or several ligands on the metal center can indeed help to modulate the reactivity of the catalysts (modulation of its Lewis acidic character and/or electron back donation) and optimize its properties for a given transformation [10]. 

The cycloisomerization of l, -enynes promoted by gold complex catalysts, are known to go through only the third pathway. This high selectivity is due to two main reasons (1) the fragment [AuL]" has only one vacant site, thus it can not coordinate simultaneously the alkyne and the alkene moieties, (2) oxidative addition processes are not facile for gold complexes [24, 157, 158]. In general, gold(I) complexes surpass the reactivity shown by platinum(ll) and other electrophilic metals for the reaction of enynes. ... 

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