Solvent controlled catalysis: Synthesis of aldehyde, acid or ester by selective oxidation of benzyl alcohol with gold nanoparticles on alumina

• Published in: Applied catalysis. A, General Vol. 485; pp. 202 - 206
• Main Authors: RAUTIAINEN, Sari, SIMAKOVA, Olga, HONGFAN GUO, LEINO, Anne-Riikka, KORDAS, Krisztián, MURZIN, Dmitry, LESKELÄ, Markku, REPO, Timo
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier 05.09.2014
• Subjects: Benzaldehyde; Benzoic acid; Benzyl alcohol; Catalysis; Chemistry; Colloidal state and disperse state; Esters; Exact sciences and technology; General and physical chemistry; Oxidation; Physical and chemical studies. Granulometry. Electrokinetic phenomena; Selectivity; Solvents; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Solvent effect; Gold; Binary compound; Catalytic reaction; Nanoparticle; Solvent-controlled; Alcohol; Transition metal; Benzyl alcohol; Aldehyde; Supported catalyst; Gold catalysts; Selective oxidation; Heterogeneous catalysis; Ester; Synthesis; Acids; Biphasic solvent; Oxidation; Alumina
• ISSN: 0926-860X; 1873-3875
• DOI: 10.1016/j.apcata.2014.08.003

As shown herein, selectivity of aerobic oxidation of benzyl alcohol with gold nanoparticles dispersed on Al sub(2)O sub(3) support is solvent-controlled. Using different solvents, the reaction was directed toward a variety of products: benzaldehyde, benzoic acid or benzoic esters were selectively produced from benzyl alcohol depending on the conditions. In toluene, benzaldehyde was produced with high selectivity, while quantitative conversion to benzoic acid was achieved in alkaline water. In methanol, methyl benzoate was produced with very high yield. Moreover, activity of the catalyst was dramatically improved without loss of selectivity in biphasic media; with a toluene/alkaline water system the highest TOF for benzoic acid synthesis was close to 5200 h super(-1), selectivity being 98%.