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Reflectance FTIR spectroscopy (RAIRS) data for the adsorption of methyl pyruvate (MP) on both clean and (+/-) -1-(1-naphthyl) ethylamine (NEA)-modified Pt(111) is reported. Study on the asymmetric hydrogenation in Ortio reaction suggest the presence of a majority of enediolate state on the clean surface and H-bond interaction between a condensed overlayer of MP and chemisorbed NEA.

Preferential C-C bond activation of methyl pyruvate on Ni(111) yielding surface methoxycarbonyl is investigated.

Thermal desorption of covalently functionalized SWNT was followed using Raman, X-ray photoemission (XPS), and thermodesorption (TDS) spectroscopies. By functionalizing different sources of SWNT, we assess the thermal stability of phenyl- and methylene-SWNT derivatives in relation to the source diameter and helicity distribution. For all samples, broad desorption features were observed at approximately 600 K for the phenyl-SWNT and at approximately 500 K for the methylene-SWNT derivatives. In both cases, no influence on helicity and on diameter was observed for the range studied. The study shows that the stability of methylene addends on SWNT is inferior to that of the phenyl and proves that the main desorption pathway of phenyl addends is a phenyl-phenyl coupling reaction.

Trifluoroacetophenone (TFAP) forms C O...H-C bonded dimers and trimers at room temperature on Pt(111). It is proposed that these systems mimic the prochiral carbonyl-chiral modifier interaction in the enantioselective hydrogenation of TFAP on cinchona-modified Pt catalysts. That is, the activation of TFAP in homomolecular assemblies at racemic sites is expected to be roughly the same as in the diastereomeric complex formed at chiral sites. This interpretation suggests a reason why alpha-phenyl ketones do not display a strong measured rate enhancement effect in the Orito reaction.

The asymmetric hydrogenation of alpha-ketoesters on cinchona-modified supported platinum particles is a prototype reaction in heterogeneous chiral catalysis. The catalysis literature shows that the reaction is highly metal-specific, that it displays rate-enhancement with respect to the racemic reaction on the nonmodified surface, and that the observed stereoselectivity is a sensitive function of substrate and modifier structure. This set of observations has proven difficult to rationalize within the context of existing models for the mechanism of the Orito reaction. The most widely discussed mechanistic models are based on the formation of chemisorbed 1:1 complexes through H-bonding between the quinuclidine function of the cinchona modifier and the prochiral, keto-carbonyl, function of the substrate. Recent surface science studies, as well as advances in the area of C-H...O hydrogen bonding, suggest that chemisorption-induced polarization may lead to an aromatic-carbonyl H-bonding interaction between the aromatic anchor of the modifier and the coadsorbed substrate. By specifying that the aromatic C-H...O interaction is to the prochiral carbonyl and that it is accompanied by a H-bonding interaction between the ester carbonyl and the quinuclidine function, we show that it is possible to rationalize essentially all of the catalysis literature for the Orito reaction in terms of a single molecular mechanism. The generality of the proposed mechanistic model is demonstrated by addressing data from the literature for a representative range of substrates, modifiers, solvents, and metals. Results of catalytic tests on an asymmetric diketone substrate are presented in support of the model.