Although homogeneous gold catalysis was known previously, an exponential growth was only induced 12 years ago. The key findings which induce that rise of the field are discussed. This includes early reactions of allenes and furanynes and intermediates of these conversions as well as hydroarylation reactions. Other substrate types addressed are alkynyl epoxides and N-propargyl carboxamides. Important vinylgold intermediates, the transmetalation from gold to other transition metals, the development of new ligands for gold catalysis, and significant contributions from computational chemistry are other crucial points for the field highlighted here.

Gold-Catalyzed Organic Reactions

Despite occasional references in the older literature to the ability of gold to catalyze certain reactions, the metal has until recently had the reputation of being one of the least catalytically useful. The recent discovery that some supported gold catalysts can affect the oxidation of carbon monoxide at or below ambient temperature has, however, focused attention on the metal's ability in this respect. For oxidation of carbon monoxide at low temperature, catalysts comprising small (<5 nm) gold particles supported preferably on an oxide of the first transition series (e.g., TiO2, α-Fe2O3) are needed. Deposition–precipitation and coprecipitation are better methods than impregnation for this purpose and provide the desired intimacy of contact between metal and support. High activity may well originate at sites at the gold–support interface, with the support making a vital contribution. Stable activity can result by optimizing aging in solution during the preparation, and low calcination temperatures are ge...

Catalysis By Gold

One of the important physical-chemical properties that characterizes the interaction of solid surfaces with gases is the bond energy of the adsorbed species. The determination of the bond energy is usually performed indirectly by measuring the heat of adsorption (or heat of desorption) of the gas [1, 2], In order to define the heat of adsorption, let us consider the chemisorption of a diatomic molecule, X2, onto a site on a uniform solid surface, M. The molecule may adsorb without dissociation to form MX2. M represents the adsorption site where bonding occurs to a cluster of atoms or to a single atom. In this circumstance, the heat of adsorption, ΔHads, is defined as the energy needed to break the MX2 bond:

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Heats of Chemisorption of O2, H2, CO, CO2, and N2 on Polycrystalline and Single Crystal Transition Metal Surfaces

Adsorption of oxygen and hydrogen on Au(110)-(1 × 2)

Untersuchung von oberflächenreaktionen mittels beugung langsamer elektronen (LEED): I. Wechselwirkung von O2 und N2O mit (110)-, (111)- und (100)-Kupfer-Oberflächen

J. Pritchard

Papers

Surface potential measurements. The adsorption of hydrogen by group 1B metals