ANON®, cyclohexanone

Amieliese Zementwerke AG, 160 ANON , cyclohexanone, 17 Antlu acene, 17... 

Anon, n. Anon (cyclohexanone). T.N. anordnen, v.t. arrange, regulate, order. Anordnung, /, arrangement, disposition, regulation. 

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 stiU employ two major reaction stages. The first reaction stage is the production of the intermediates cyclohexanone [108-94-1] and cyclohexanol [108-93-0], usuaHy 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 the 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 worldwide basis, but not in the United States. 

The selective protection of the 17-ketone is difficult to achieve in the presence of other carbonyl groups on account of the reduced reactivity of cyclopent-anones as compared to cyclohexanones. On the other hand, cleavage of a... 

A similar acetylation procedure (without p-toluenesulfonic acid) has been employed to prepare other /3-diketones.5 As examples, cyclohexanone was converted to 2-acetylcyclohex-anone (73%) cyclopentanone yielded 2-acetylcyclopentanone (80%) 3-pentanone yielded 3-methyl-2,4-hexanedione (81%) dibenzyl ketone yielded l,3-diphenyl-2,4-pentanedione (72%), and acetophenone gave benzoylacetone (70%). 

Treatment of 2-butyne with ozone leads to unstable primary ozonides that cleave to cr-oxo-carbonyl oxides these could be trapped in the presence of aldehydes or ketones affording cross- -oxo-l, 2,4-trioxolanes. Subsequent cycloadditions between such cr-oxo-ozonides and cyclohexanone oxide, generated in situ from O-methylcyclohex-anone oxime (which affords methyl nitrite as a side-product), yield cr-diozonides 101 (Scheme 30) <1997J(P1)1601>. 

In a similar reaction various acyloxy-substituted alkynes were ozonolyzed in the presence of O-methylcyclohex-anone oxime affording more complex a-diozonides. An X-ray crystallographic determination revealed that the compound with R1 = Ph and R2 = CH2-0-C0-Ph is a single diastereomer 102 formed by the approach of the cyclohexanone oxide to the carbonyl group of the intermediate bicyclic ozonide from the less hindered exo-face (Scheme 31) <1997J(P1)1601>. 

The use of silyl enol ethers for sulphonyloxylations offers some advantages over ketones conditions are milder and yields higher (85% for oc-tosyloxy-cyclohex-anone) also, it is possible to control the regiochemistry of the reaction. For example, 2-methyl-6-tosyloxy-cyclohexanone was prepared regioselectively from the corresponding silyl enol ether, without heating. 

Benzothiophen 2-Amino-3-ethoxycarbonyl-6-methyl- E6a, 225 (Cyclohexanon + NC-CH2-COOR/S8) Butansaure 2-Amino-3-benzylthio-3-methyl- Xl/2, 453 4H-[Pg.1044]

However, bromination in acetic acid at 0-5 C did give mainly 103 which rearranged slowly at room temperature to 105. The morpholine enamine of 2-methylcyclohex-anone exists as a mixture of 52% less and 48% more substituted isomers (106a,b). The greater reactivity of the former has been utilized as a means of separating the brominated products. Thus, treatment of the mixture of enamines with 0.52 equivalents of bromine results in precipitation of the 6-bromoiminium salt (107), which can be filtered off and hydrolysed to the 2,6-disubstituted cyclohexanone (108). The less reactive isomer (106b) remains in solution and can then be brominated in the same way to give a precipitate of the 2-bromoiminium salt and hence the 2,2-disubstituted cyclohexanone (1(19) on hydrolysis (Scheme 98). 

Cyclohexanone Anone Hytrol O Nadone Pimelic Ketone Sextone... 

ANOL (108-94-1) see cyclohexanone. ANOL (108-93-0) see cyclohexanol. ANONE (108-94-1) see cyclohexanone. ANOZOL (84-66-2) see diethyl phthalate. ANPROLENE (75-21-8) see ethylene oxide. 

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,... 

Behari et al. (1982b) find that ceric oxidation of cyclohexanone and methylcyclohex-anone in sulfuric acid solutions do conform to the Michaelis-Menten rate law. By comparing the rate of oxidation with that for enolization (determined by reaction rate for the substrate with iodine), the authors establish that the reaction must involve the ketonic form of the substrate. Earlier results reported by Benson (1976) agree with this assessment and suggest further that a C-H bond is broken in the rate-determining step. The authors are unable to resolve the rate and equilibrium parameters for electron transfer and precursor complex stability. The cyclic ketones are oxidized nearly an order of magnitude faster and under milder conditions than the aliphatic ketones. 

These conformational preferences can be used for the control of reaction stereoselectivity. For example, whereas the reduction of 4-Me-cyclohexanone mostly gives the trans product, reduction of the 4-Cl-cyclohex-anone leads to the preferential formation of the cis product. Assuming the common axial preference for the nucleophilic attack at the carbonyl, the differences in reaction selectivity should reflect the different axial/ equatorial populations of the two carbonyl reactants. Similar conformational preferences were suggested for the nucleophilic attack at oxonium ions (Figure 6.89). ... 

Within the scope of its program aimed at process improvements, the Corporate Department for Research and Patents of DSM is now seeking ways of optimizing the cyclohexane oxidation route towards cyclohexanone (anone) and cyclohexanol (anol). These products are Intermediates in the preparation of caprolactam. Caprolactam is polymerised to nylon-6. As DSM has a great interest in the world production of caprolactam, much effort is put into research and optimization of the various process steps. 

Figure 2 (A) The model, (B) both enantiomers of 3-methyl-cyclohexanone acetalysed with (2R, 3R)-butane-2,3-diol and fitted in the model, and (C) both enantiomers of 2-methylcyclohex-anone acetalysed with (2R, 3/ )-butane-2,3-diol and fitted in the model. Reprinted with permission from Lemiere GL, Dommisse RA, Lepoivre JA ef a/(1987) Determination of the absolute configuration of six-membered-ring ketones by NMR. Journal of the American Chemical Society 109 1363-1370. Copyright (1987) American Chemical Society.

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