Oxidative dehydrogenation of alcohols on gold: An experimental and computational study on the role of water and the alcohol chain length

Selective vapor-phase formation of dimethylformamide via oxidative coupling of methanol and dimethylamine over bimetallic catalysts

“…Two possible explanations for the observed increase in DMF selectivity are: first, hydroxyl groups from excess water recombine and leave behind atomic oxygen on Au where selective oxidation reactions occur 22,41–44,48 and second, hydroxyl groups occupy Pd–O sites that form in oxidant-rich conditions. Since palladium oxide catalyzes complete combustion of methanol, 78 mobile hydroxyl groups formed from water could occupy sites for complete oxidation, leading to the observed increase in DMF selectivity.…”

“…The effect of co-adsorbed O/OH species are considered as they may assist with dehydrogenation steps and lower the reaction barrier. 48,91 Species that are bound to the surface are indicated with * and adsorption/desorption steps are not shown.…”

“…Another possible mechanism for supplying oxygen adatoms to Au surfaces is by water-facilitated migration. 40–44,48 In this mechanism, water adsorbs to the surface and dissociates to supply a surface hydrogen to an oxygen atom already present on the surface, typically originating from O 2 dissociation at the Au–support interface 45 or unintentional metal impurities 37,38 and resulting in two mobile surface hydroxyl groups. Experiments with isotopically labelled 18 O water over Au(110) demonstrated that recombination of hydroxyls to form water and an adsorbed oxygen adatom has a small energy barrier of 14.5 kJ mol −1 .…”

Bridging and terminal hydroxyl groups of Zr(OH)4 as active sites for the ultraselective transformation of biomass-based alcohols

“…[16][17][18] Moreover, the oxidative dehydrogenation of alcohols to corresponding carbonyl compounds and dehydration of alcohols to corresponding alkene compounds play important roles in academic organic chemistry research and industrial application. [19][20][21] As a typical biomass-based alcohol monomeric molecule, 1-phenylethanol can be transformed into a variety of organic intermediates, such as acetophenone and styrene. [22][23][24] Numerous types of research on the oxidation of 1-phenyl ethanol using both homogenous and heterogenous (Pd, Ru, Au, Ag, etc.)…”