Nitric acid cyclohexene oxidation with

Cyclopentanecarboxaldehyde has been prepared by the procedure described above 2 3 by the reaction of aqueous nitric acid and mercuric nitrate with cyclohexene 6 by the action of magnesium bromide etherate 6 or thoria 7 on cyclohexene oxide by the dehydration of frarei-l, 2-cyclohexanediol over alumina mixed with glass helices 8 by the dehydration of divinyl glycol over alumina followed by reduction 9 by the reaction of cyclopentene with a solution of [HFe(CO)4] under a carbon monoxide atmosphere 10 and by the reaction of cyclopentadiene with dicobalt octacarbonyl under a hydrogen and carbon monoxide atmosphere.11... 

Examples of organic reactions in green solvents abound. One example is described in the oxidation of cyclohexenes with 30% hydrogen peroxide (Sato et al., 1998). Cur-rendy, the industrial production of adipic acid uses nitric acid oxidation of cyclohexa-... 

This solvent- and halide-free oxidation of cyclohexene and cyclopentene is clean, safe, and reproducible, with conditions that are less corrosive than those of the nitric acid oxidation. No operational problems are foreseen for a large-scale version of this green process, and technical refinement should further increase the synthetic effi-... 

Adipic acid historically has been manufactured predominantly from cyclohexane and, to a lesser extent, phenol. During the 1970s and 1980s, however, much research has been directed to alternative feedstocks, especially butadiene and cyclohexene, as dictated by shifts in hydrocarbon markets. All current industrial processes use nitric acid in the final oxidation stage. Growing concern with air quality may exert further pressure for alternative routes as manufacturers seek to avoid NO, abatement costs, a necessary part of processes dial use nitric acid. 

High yields to AA were obtained when a Co/Mn cluster complex was used, which was superior to the individual Co and Mn acetates [14kj at 90 ° C, and 37 atm pressure, in acetic acid and water solvents, the oxidation of cyclohexanone with air gave complete conversion and 76.3% yield to AA. The authors suggested that 1-hydro-xo-cyclohexen-2-one, the tautomeric form of 1,2-cyclohexandione, is the precursor for the formation of the glutaric and succinic acid by-products. Excellent yields were also reported [14m] for the oxidation of cyclohexanone using Mn(N03)2 and Co(N03)2 (molar ratio 1 1) in the presence of oxygen and catalytic quantities of nitric acid at atmospheric pressure. The conversion was 97.5% and the selectivity to AA was 93.4%. 

Cyclohexene can be synthesized by partial hydrogenation of benzene, by partial dehydrogenation of cyclohexane, or by dehydrohalogenation of cyclohexyl halides. The hydrogenation of benzene is the most viable route in the Asahi process, cyclohexene is obtained with a 60% yield and 80% selectivity, with the remainder being converted into cyclohexane. Asahi has developed a process for the addition of water to cyclohexene to produce cyclohexanol that can then be oxidized to AA using the conventional nitric acid oxidation. 

The structures of the phosphorate products have not been established with certainty. They appear to contain an anhydride structure, since they react vigorously with water and with alcohols. Oxidative hydrolysis of the product from cyclohexene with 40% nitric acid liberates half of the phosphorus as phosphoric acid, and gives a phosphonic acid which can be isolated as the lead salt (28,32). The analysis of the lead salt is in agreement structure I (28,29>. It seems likely, however,... 

To investigate the reaction of mineral acids with cyclohexene oxides by GC-MS. To determine the concentrations of hydrochloric and nitric acid in a simulated stack emission. 

Investigation of the reaction of hydrochloric and nitric acid with cyclohexene oxide. For the Hewlett Packard 5890 GC coupled to the 5971 Mass Sensitive Detector the instrument settings are as follows ... 

Method (a) uses nitric acid for the oxidation of the mixture of cyclohexanol/cyclohexanon available by the hydrogenation of phenol process (b) is based on hydroxycarbonylation of 1,3-butadien and process (c) on a catalytic green chemistry reaction with water as the only side product. In this process, cyclohexene is oxidized hy hydrogen peroxide in the presence of tungsten-hased catalyst under phase-transfer catalysis (PTC). 

Hessel et al. described a full process design vision for the manufacturing of adipic acid on an industrial scale [66,67]. Currently, commercial production of adipic acid comprises two reaction steps. The first step involves the selective oxidation of cyclohexane to KA oil, a mixture of cyclohexanone and cyclohexanol. The second step consists of oxidation of the KA oil to adipic acid with an excess of nitric acid in the presence of copper or vanadium catalysts. In contrast, Hessel et al. suggest that a new and direct route toward adipic add based on the direct oxidation of cyclohexene with hydrogen peroxide would be much more cost effective. This process is based on the protocol described by Noyori and coworkers and utilizes a... 

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