Solid-State Oxidation of Alcohols in Gold-Coated Milling Vessels via Direct Mechanocatalysis

This paper presents a novel approach for the selective oxidation of alcohols to their corresponding aldehydes through direct mechanocatalysis, employing a gold-coated milling vessel as catalyst and air as the oxidation agent. By adjusting milling frequency, media, and duration, high catalytic efficiencies and selectivities are achieved. Remarkably, yields of up to 99 % are obtained for specific substrates, with a turnover number (TON) of 8200 and a turnover frequency (TOF) of 0.77 s-1, surpassing existing alternatives. Confirmation of the catalytic reaction indeed occurring on the milling tool surface was achieved through X-ray photoelectron spectroscopy (XPS).

Bulk gold catalyzes hydride transfer in the Cannizzaro and related reactions

Disproportionation reactions of benzaldehyde and benzyl alcohol are catalyzed by bulk gold with hot water as the only other reagent.

A Rational Solid-State Synthesis of Supported Au-Ni Bimetallic Nanoparticles with Enhanced Activity for Gas-Phase Selective Oxidation of Alcohols

A facile confined solid-state seed-mediated alloying strategy is applied for the rational synthesis of supported Au-Ni bimetallic nanoparticles (BMNPs). The method sequentially deposits nickel salts and AuNP seeds into the ordered array of extra-large mesopores (EP-FDU-12 support) followed by a high-temperature annealing process. The size, structure, and composition of the AuNi BMNPs can be well tuned by varying the AuNP seeds, annealing temperature, and feeding ratio of metal precursors. Kinetic studies and DFT calculations suggest that the introduction of the Ni component can significantly prompt the O₂ activation on AuNPs, which is critical for the selective alcohol oxidation using molecular O₂ as the oxidant. The optimal Au-Ni BMNP catalyst showed the highest turnover frequency (TOF) (59 000 h^-1, 240 °C) and highest space-time yield (STY) of benzyl aldehyde (BAD) productivity (9.23 kg·g_Au^-1·h^-1) in the gas-phase oxidation of benzyl alcohol (BA), which is at least about 5-fold higher than that of other supported Au catalysts.

Oxidation of benzyl alcohol catalyzed by gold nanoparticles under alkaline conditions: weak vs. strong bases

A comparative study of the promotion effect of weak and strong bases in the aqueous oxidation of benzyl alcohol by Au/TiO₂ showed that better conversion and aldehyde selectivity can be obtained using weak bases.

Iron-catalyzed aerobic oxidative functionalization of sp3 C–H bonds: a versatile strategy for the construction of N-heterocycles

Iron-catalyzed aerobic oxidative functionalization of sp³ C–H bonds using a biofriendly iron catalyst in combination with O₂ or air as the sole oxidant has been developed for the construction of N-heterocycles from easily available carboxylic acid derivatives and o-substituted anilines.

Thermally stable gold/alumina aerogel catalysts prepared by a simultaneous synthesis process for solvent-free aerobic benzyl alcohol oxidation

Gold nanoparticles physically trapped in the framework of alumina aerogel exhibit excellent thermal stability and catalytic activity at high temperature.