Cydohexanol oxidation

A similar retardation effect of cosolvent was reported previously for benzene oxidation [90, 91]. The solvent may compete with reactant for diffusion in the channels and adsorption at the active sites of TS-1 catalyst. The activity Ti-beta for 1-hexene and cydohexanol oxidations is highest in acetonitrile, which is a polar, nonprotic solvent [92]. This is in contrast with the observed enhancement of the activity of TS-1 by methanol and protic solvents [68]. These differences have been... 

Reactions. w-Hydroxybenzoic acid affords a variety of products, depending on the catalyst and conditions employed. Catalytic reduction over platinum black or platinum oxide in alkaline solution gives 3-hydroxycyclohexanecarboxylic acid [22267-35-2]. Reduction of a warm aqueous solution over platinum oxide or over colloidal platinum yields cyclohexanecarboxylic acid. w-Hydroxybenzaldehyde can be prepared by reducing ///-hydroxybenzoic acid with sodium amalgam. Finally, reduction over Raney nickel gives cydohexanol. 

Hydrocarbon Oxidation. The oxidation of hydrocarbons (qv) and hydrocarbon derivatives can be significantly altered by boron compounds. Several large-scale commercial processes, such as the oxidation of cyclohexane to a cydohexanol—cyclohexanone mixture in nylon manufacture, are based on boron compounds (see Cylcohexanol and cyclohexanone Fibers, polyamide). A number of patents have been issued on the use of borate esters and boroxines in hydrocarbon oxidation reactions, but commercial processes apparently use boric acid as the preferred boron source. The literature in this field has been covered through 1967 (47). Since that time the literature consists of foreign patents, but no significant applications have been reported for borate esters. 

BASF. In the Badische process, cyclohexanone is produced by liquid-phase catalytic air oxidation of cyclohexane to KA oil, which is a mixture of cyclohexanone and cydohexanol, and is followed by vapor-phase catalytic dehydrogenation of the cydohexanol in the mixture. Overall yidds range from 75% at 10% cydohexane conversion to 80% at 5% cydohexane conversion. 

Dutch State Mines (Stamicarbon). Vapor-phase, catalytic hydrogenation of phenol to cyclohexanone over palladium on alumina, licensed by Stamicarbon, the engineering subsidiary of DSM, gives a 95% yield at high conversion plus an additional 3% by dehydrogenation of coproduct cydohexanol over a copper catalyst. Cyclohexane oxidation, an alternative route to cyclohexanone, is used in the United States and in Asia by DSM. A cyclohexane vapor-cloud explosion occurred in 1975 at a co-owned DSM plant in Flixborough, UK (12) the plant was rebuilt but later closed. In addition to the conventional Raschig process for hydroxylamine, DSM has developed a hydroxylamine phosphate—oxime (HPO) process for cyclohexanone oxime no by-product ammonium sulfate is produced. Catalytic ammonia oxidation is followed by absorption of NOx in a buffered aqueous phosphoric acid... 

A recent paper by Kwiatek and co-workers1891 discloses the use of a homogeneous catalysis system for the hydrogenation of epoxides. Reduction of cyclohexene oxide to cydohexanol, and of styrene oxide to 2-phenylethanol, was carried at atmospherio pressure, using Ks[Co(CN) ] to catalyze the reaction. 

Cydohexene oxide was first prepared by Brunei from o-iodo-cydohexanol and solid potassium hydroxide.1 It has also been obtained by the oxidation of cydohexene with benzoyl hydroperoxide.2... 

Cyanogen Cyclohexane Cydohexanol Cyclohexanone Cydohexene Demeton V Deuterium oxide DDVP, see Dichlorvos... 

We prepared Ru(TPFPP)(CO) (33) complex for the first time, and showed it to be an efficient catalyst for the aerobic oxidation of alkanes using acetaldehyde [156]. Thus, the 33-catalyzed oxidation of cyclohexane with molecular oxygen in the presence of acetaldehyde gave cyclohexanone and cydohexanol in 62% yields based on acetaldehyde with high turnover numbers of 14 000 (Eq. 3.100). 

In the oxidation of cydohexanol to cyclohexanone, what purpose does the acetic acid serve ... 

Two variants are currently employed for the synthesis of Ol/One (i) the hydrogenation of phenol to cydohexanol and cyclohexanone and (ii) the hydration of cyclohexene to cydohexanol cydohexene is synthesized by the selective hydrogenation of benzene. Cydohexanol is then oxidized to AA using the same process as that employed for the nitric acid oxidation of the KA Oil. 

These processes involve two stages. Cyclohexane is first oxidized to a cydohexanol/ cyclohexanone mixture (see Section 9.1.6.1 and Section 121.22X which is then dehydrogenated (Fig. 121IX This Ol/One mixture is first fractionated in a series of three distillation columns operating under vacuum, of which the first two (20 trays each) separate the... 

Since adipic acid has been produced in commercial quantities for almost 50 years, it is not surprising that many variations and improvements have been made to the basic cyclohexane process. In general, however, the commercially important processes still employ two major reaction stages. The first reaction stage is the production of the intermediates cyclohexanone [108-94-1] and cydohexanol [108-93-0], usually abbreviated as KA, KA oil, ol-one, or anone-anol. The KA (ketone, alcohol), after separation from unreacted cyclohexane (which is recycled) and reaction by-products, is then converted to adipic acid by oxidation with nitric acid. An important alternative to this use of KA is its use as an intermediate in die manufacture of caprolactam, the monomer for production of nylon-6 [25038-54-4]. The latter use of KA predominates by a substantial margin on a woddwide basis, but not in the United States. 

Cyclohexanone. KetohexamethyJene pimelic ketone Hyrrol O Anone Nadone. C4H 0O mol wt 98.14. C 73,43%, H 10.27%, O 16.30%. Obtained from cydohexanol by catalytic dehydrogenation or by oxidation (which yields cyclohexanone and adipic acid) Or from cyclohexane by oxidation (yielding cyclohexanone and cydohexanol) Brit,... 

Oxidation of cyclohexane Compared to VS-2, V-NCL-1 is more active (TON = 7.3 vs. 2.0) in the oxidation of cyclohexane to cydohexanol and cyclohexanone (Table 2). The HjOj efficiency is also higher on V-NCL-1 (53.3 vs. 33.0). This superior performance may be partly due to the large-pore character and a lower concentration of vanadium in V-NCL-1. On both the catalysts, the mono-functional product selectivity is high (about 94-95%) and the cydohexanol to cydohexanone ratio is simiiar. The catalysts after separation from the products, washing and reactivation were found to be as active as the fresh, caicined samples. 

Purpose. You will carry out the nitric add oxidation of cydohexanol to obtain adipic acid, an intermediate in the route to prepare nylon, a polyamide. 

A new strategy for E-caprolactone synthesis is outlined in Scheme 6.9. The aerobic oxidation of cydohexanol (3) catalyzed by N H PI gives a mixture of cyclohexanone (2)... 

Cydohexane is the most important cyclic alkane in industrial organic chemistry and plays a major role in the industrial production of important monomers, such as, for example, adipinic add, adipodinitrile, hexamethylenediamine, hexamethy-lene diisocyanate, and Eproduction processes cyclohexane is oxidized in the first step in a liquid-phase reaction to a mixture of cydohexanol and cyclohexanone. Details about this process are given in Sedion 5.3.3.1. 

Phenol production is typically carried out by add induced conversion of cumene hydroperoxide to phenol and acetone (Hock process). Cumene hydroperoxide is obtained by oxidation of cumene. The cumene feedstock for the latter reaction is provided by Friedel-Crafts alkylation of benzene with propene. Alternative routes (chlorobenzene hydrolysis, cydohexanol dehydrogenation, oxidative decarboxylation of benzoic acid) exist but are of much lower industrial relevance. 

Among the industrially produced lactams, e-caprolactam has by far the highest production capacity due to its important role as monomer in the polyamide business. There exist several synthetic routes to produce e-caprolactam. The most important one starts from benzene (Scheme 5.3.7). Benzene is hydrogenated in a first step to cyclohexane, followed by oxidation of the latter to a mixture of cyclohexanone and cydohexanol. This mixture is then reacted with NH2OH to give cyclohexanone oxime, which is converted under add catalysis in a so-called Beckmann rearrangement reaction to e-caprolactam. Alternative routes try to avoid the oxime intermediate (UCC peracetic add process via e-caprolactone), try to avoid the cydohexanone intermediate (e.g., DuPont process converting cydohexane directly into the oxime intermediate by reaction with nitric add), or start from toluene (Snia-Viscosa process). 

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