Cyclohexanone In Water Research Articles

Aqueous-phase selective hydrogenation of phenol to cyclohexanone over soluble Pd nanoparticles

The water-soluble Pd nanoparticles are highly-efficient catalysts for the selective hydrogenation of phenol to cyclohexanone in water under mild conditions.

A Tuneable Bifunctional Water‐Compatible Heterogeneous Catalyst for the Selective Aqueous Hydrogenation of Phenols

AbstractA water‐tolerant bifunctional heterogeneous catalyst is able to effectively catalyse the selective hydrogenation of phenol to cyclohexanone in water at atmospheric pressure and room temperature with >99.9% selectivity to cyclohexanone at phenol conversions >99.9%. The catalyst was found to be highly active and reusable, giving identical activities and selectivities after >5 uses. Moreover, this reported simple bifunctional catalyst is also able to hydrogenate a range of substituted phenols in high yields under the investigated aqueous conditions.

Cellulose nanocrystallites as an efficient support for nanoparticles of palladium: application for catalytichydrogenation and Heck coupling under mild conditions

We report herein the synthesis of a new hybrid material, PdNPs@CNCs consisting of monodisperse Pd nanoparticles (PdNPs) evenly deposited onto colloidal cellulose nanocrystallites (CNCs). This material proved an active catalyst for the hydrogenation reaction of phenol to cyclohexanone in water as a solvent, at room temperature, under 4 bar of dihydrogen. Moreover, the catalyst perfomed well in the Heck coupling of styrene and iodobenzene in a hydro-organic mixture. CNCs constitute a highly crystalline, ordered and yet accessible green material easily obtained from wood pulp. This work demonstrates the possibility of using colloidal CNCs as an efficient support for catalysis.

ChemInform Abstract: Cs2.5H0.5PW12O40 Catalyzed Diastereoselective Synthesis of β‐Amino Ketones via Three Component Mannich‐Type Reaction in Water.

Abstract A series of insoluble salts of Keggin heteropoly compounds were prepared and used as catalysts for the Mannich-type reaction of benzaldehyde, aniline, and cyclohexanone in water. Among them, Cs2.5H0.5PW12O40 showed excellent catalytic activity. Effects of surfactant, catalyst loading and temperature were studied to introduce the best reaction condition. The optimized reaction conditions were extended to Mannich reaction of various aldehydes, ketones, and amines in water. This rapid procedure afforded structurally divers β-amino ketones with major anti diastereoselectivity. Additionally, four new compounds were reported. The catalyst was recovered and reused for subsequent runs.

Cs 2.5H 0.5PW 12O 40 catalyzed diastereoselective synthesis of β-amino ketones via three component Mannich-type reaction in water

A series of insoluble salts of Keggin heteropoly compounds were prepared and used as catalysts for the Mannich-type reaction of benzaldehyde, aniline, and cyclohexanone in water. Among them, Cs 2.5H 0.5PW 12O 40 showed excellent catalytic activity. Effects of surfactant, catalyst loading and temperature were studied to introduce the best reaction condition. The optimized reaction conditions were extended to Mannich reaction of various aldehydes, ketones, and amines in water. This rapid procedure afforded structurally divers β-amino ketones with major anti diastereoselectivity. Additionally, four new compounds were reported. The catalyst was recovered and reused for subsequent runs.

Ozonation of Cyclohexanol and Cyclohexanone in Water under Ultraviolet Irradiation.

Cyclohexanol and cyclohexanone were used in large quantity as materials for chemical products, for example, for the synthesis of adipic acid. In this paper, the process of ozonation of cyclohexanol and cyclohexanone under ultraviolet irradiation was studied. Ozonation combined with ultraviolet irradiation was used for the destruction of organic refractry in water. Cyclohexanol and cyclohexanone were readily oxidized to give adipic acid, glutalic acid, succinic acid, malonic acid, glycolic acid and their derivatives, which were further oxidized to give oxalic acid and formic acid. Simultaniously, the total organic carbon decreased effectively. By the ozonation under neutral conditions without ultraviolet irradiation, cyclohexanone was not oxidized, but cyclohexanol was oxidized to give cyclohexanone. On the basis of these results, it was found that the ozonation under ultraviolet irradiation was markedly effective for the degradation of cyclohexanol and cyclohexanone, compared with the ozonation alone.

Change in systolic blood pressure among treated hypertensives resulting from a community-based health education campaign: Pamela J. Curry, Stanford University School of Medicine, Stanford, California; William L. Haskell; Byron W. Brown; John W. Farquhar

A series of Pd catalysts were prepared on different supports (Fe2O3, SiO2, ZnO, MgO, Al2O3, carbon, and Amberlyst-45) and used in the selective hydrogenation of phenol to cyclohexanone in water. The Amberlyst-45 supported Pd catalyst (Pd/A-45) was highly active and selective under mild conditions (40–100 °C, 0.2–1 MPa), giving a selectivity of cyclohexanone higher than 89% even at complete conversion of phenol. Experiments with different Pd loadings (or different particle sizes) confirmed that the formation of cyclohexanone was a structure sensitive reaction, and Pd particles of 12–14 nm on Amberlyst-45 gave better selectivity and stability.