LIQUID-PHASE OXIDATION OF 4-ETHYLECYCLOHEX-1-ENE BY OXYGEN OF AIR IN. PRESENCE OF CATALYTIC

The liquid-phase oxidation of 4-ethylecyclohexene by oxygen in the presence of a catalytic system (NH4)6Mo7O24 CoBr2) was investigated. The influence of various factors (temperature, duration, quantity of catalyst, molar ratios of reagents) on the oxidation reaction rates (conversion of feedstock, selectivity of reaction on oxy products) is determined

Activity of Manganese Carboxylates in the Process of Liquid-Phase Oxidation of Ethylbenzene with Atmospheric Oxygen

The process of oxidation of hydrocarbon with oxygen proceeds with formation of the corresponding hydroperoxide as the primary product [1,2]. A catalyst is the most important factor that influences on the direction of flow of the oxidation reaction. Catalysts based on metals of variable valency, and their derivatives are the most active in reactions of oxidation of hydrocarbon [3].

Identification of the Crystalline Product of Liquid-Phase Oxidation of α-Pinene with Atmospheric Oxygen in the Presence of Cobalt (II) Stearate

One of the possible directions of liquid-phase oxidation of α-pinene by atmospheric oxygen leads to the formation of a mixture of terpene oxygen-containing compounds (epoxides, alcohols, ketones, etc.). The problem of this direction is the formation of a large amount of 2,3-epoxypinane which over time turns into trans-sobrerol, campholene aldehyde, trans-pinocarveol, trans-carveol, and trans-3-pinen-2-ol as a result of hydrolysis. One of the abovementioned substances with a solid crystalline structure is trans-sobrerol. Sobrerol is widely used in perfumery for synthesis of synthetically fragrant substances and pharmaceutical industry, in particular, it is a part of medicines with mucolytic action, as well as in the treatment of headaches and diseases such as rhinorrhea and chronic bronchitis. The aim of this work is to identify a crystalline product produced by liquid-phase oxidation of α-pinene with atmospheric oxygen in the presence of cobalt (II) stearate. The process of liquid-phase oxidation was carried out in the following conditions: temperature – 70 °С, air consumption – 16.67 cm3/s, duration – 5 h, amount of catalyst – 0.2–0.5 wt.%. Then the mixture was exposed to steam distillation in order to separate monomers (they contain terpene oxygen-containing compounds and hydrocarbons) from polymers. As a result of settling and storage of the mixture, crystals were found and isolated from the mother liquor solution. Their identification was carried out using IR and 13C NMR spectroscopy as well as scanning electron microscopy. It was found that the spatial organization of the isolated crystals and the standard sample (Sigma Aldrich) is represented by multilayer rectangular plates. Analysis of the IR spectra of the crystals showed that the absorption band at a wave number of 3318 cm–1 corresponds to intramolecular and intermolecular hydrogen bonds in hydroxyl groups, at wave numbers of 2887, 2935, 2975 cm–1 it corresponds to methyl groups. The results obtained are comparable with the results of the IR-spectrum of the standard sample. Given the results of previous studies of 1H NMR spectrum [15] and 13C NMR spectrum, it was determined that the resulting crystalline product of liquid-phase oxidation of α-pinene is trans-sobrerol.