Cyclohexanone-2,6-dicarboxylic

DIMETHYL CYCLOHEXANONE-2,6-DICARBOXYLATE (Cyclohexanone-2,6-dicarboxylic acid, dimethyl ester)... 

Cyclohexanone added to magnesium methyl carbonate prepared from Mg, methanol, and COg in dimethylformamide (cf. Synth. Meth. 14, 709), refluxed 2 hrs. under Ng, treated at ca. 0° with satd. methanolic HCl, and allowed to stand overnight at room temp. dimethyl cyclohexanone-2,6-dicarboxylate. Y 44-45%. S. N. and M. Balasubrahmanyan, Org. Synth. 49, 56 (1969). 

G-20 Dicarboxylic Acids. These acids have been prepared from cyclohexanone via conversion to cyclohexanone peroxide foUowed by decomposition by ferrous ions in the presence of butadiene (84—87). Okamura Oil Mill (Japan) produces a series of commercial acids based on a modification of this reaction. For example, Okamura s modifications of the reaction results in the foUowing composition of the reaction product C-16 (Linear) 4—9%, C-16 (branched) 2—4%, C-20 (linear) 35—52%, and C-20 (branched) 30—40%. Unsaturated methyl esters are first formed that are hydrogenated and then hydrolyzed to obtain the mixed acids. Relatively pure fractions of C-16 and C-20, both linear and branched, are obtained after... 

Cyclohexanone undergoes dicarboxylation when treated with a 10-fold excess of MMC. When 2 g (0.02 mole) of cyclohexanone is treated with 100 ml of approx. 2 M MMC at 120-130° for 6 hours, the usual work-up procedure gives about 50% yield of 2,6-cyclohexanonedicarboxylic acid, mp 123° after recrystallization from ether-petroleum ether. 

Cyclohexanone oxime, 32, 15 Cyclohexene, 31, 66 1-Cyclohexene-l-acetonitrile, 31, 25, 26 4-Cyclohexene-1,2-dicarboxylic... 

Cyclohexanone, 2-hydroxymethyl-ene-, preparation of, 54, 38 reaction with alkylenedithio-tosylates, 54, 37 Cyclohexanone, 2,2-trimethy1-enedithio-, 54, 39 4-CYCLOHEXENE—1,2-DICARBOXYLIC ACID, DIETHYL ESTER, trans-, 50, 43... 

Aqueous NaOCl (10%, 400 ml) is added with stirring to the cycloalkanone (0.1 mol) and Aliquat (4 g, 10 mmol) at 10°C. The mixture is stirred and the pH is maintained at 12.0 by the addition of aqueous NaOH (0.5 M). On completion of the reaction, the aqueous phase is separated, washed with CH2C12 (200 ml), and acidified to pH 2.0 with HC1 (2M). The acidic solution is cooled to 0°C to cause precipitation of the dicarboxylic acids (e.g. cyclohexanone yields a mixture of adipic acid 63%, succinic acid 9%, glutaric acid 17%, and a,a-dichloroadipic acid 5%). 

Salicylic acid, upon reaction with amyl alcohol and sodium, reduces to a ring-opened aliphatic dicarboxylic acid, ie, pimelic acid (eq. 5). The reaction proceeds through the intermediate cyclohexanone-2-carboxylic acid. This novel reaction involves the fission of the aromatic ring to tfj-hexahydrosalicylic acid when salicylic acid is heated to 310°C in an autoclave with strong alkali. Pimelic acid is formed in 35—38% yield and is isolated as the diethyl ester. 

Cyclohexanedicarboxylic acid, diethyl ester, CIS-, 29 Cyclohexanone, 90 4-Cyclohexene-I, 2-dicarboxylic ACID, diethyl ester, CIS-, 29 4-Cyclohexene-1,2-dicarboxylic anhydride, CIS-, 93... 

This is a general method of preparing enamines from a secondary aliphatic amine and cyclohexanone or cyclopentanone. Acylation of such enamines is the first step in a general procedure for increasing the chain length of a carboxylic acid by 5 or 6 carbon atoms and of a dicarboxylic acid by 10 or 12 carbon atoms.6 Alkylation of enamines of cyclohexanones by alkyl halides 7 or electrophilic olefins,8 followed by hydrolysis, is a good route to a-monoalkyl cyclohexanones. 

Adipic acid [124-04-9] - [ALKYD RESINS] (Vol 2) - [DICARBOXYLIC ACIDS] (Vol 8) - [FOOD ADDITIVES] (Vol 11) - (ELECTROCHEMICALPROCESSDTG - ORGANIC] (Vol 9) -barrier polymers from [BARRIERPOLYMERS] (Vol 3) -from cyclohexane [HYDROCARBONS - C1-C6] (Vol 13) -from cyclohexane [HYDROCARBON OXIDATION] (Vol 13) -from cyclohexanol [CYCLOHEXANOL AND CYCLOHEXANONE] (Vol 7) -as food additive [FOOD ADDITIVES] (Vol 11) -nylon from [POLYAMIDES - FIBERS] (Vol 19) -nylon-6,6 from [POLYAMIDES - GENERAL] (Vol 19) -nylon-6,6 from [POLYAMIDES - PLASTICS] (Vol 19) -m polyester production [COMPOSITE MATERIALS - POLYMER-MATRIX - THERMOSETS] (Vol 7) -m polyester resins [POLYESTERS, UNSATURATED] (Vol 19) -soda preservatives [CARBONATED BEVERAGES] (Vol 5)... 

C-20 Dicarboxylic Acids. These acids have been prepared front cyclohexanone via conversion to cyclohexanone peroxide followed by decomposition by ferrous ions in Ihe presence of butadiene, Okamura Oil Mill (Japan) produces a series of commercial acids based on a modification of this reaction. 

Cyclohexanone cyanohydrin, hi 10 ds-4-Cyclohexene-1,2-dicarboximide, t75 ds-4-Cyclohexene-l,2-dicarboxylic anhydride, t74... 

Walther et al. improved the Na0Ph/C02 system by tuning the role of the solvent, such that the carboxylation of acetone was carried out selectively by sodium phenoxide with N-methyl-caprolactam under 0.1 MPa C02 to afford 3-ketoglutaric acid in 65% yield [34]. The same authors reported the conversion of acetyl-naphthalene (acetonaphthone) to acetyl-naphthalene carboxylic acid with 84% yield, and of cyclohexanone to cyclohexane-2,6-dicarboxylic acid in 56% yield. 

Clearly such a method is of limited preparative value, but an important exception is the oxidation of cyclic secondary alcohols which on oxidation with nitric acid give good yields of dicarboxylic acids by way of the intermediate cyclic ketone, e.g. adipic acid from cyclohexanone, Expt 5.123. 

An important goal is, therefore, to develop effective methods for catalytic oxidations with dioxygen, under mild conditions in the liquid phase. Two substrates which are often chosen as models for alkane oxidations are cyclohexane and adamantane. Cyclohexane is of immense industrial importance as its oxidation products - cyclohexanone and adipic acid - are the raw materials for the manufacture of nylon-6 and nylon-6,6. Adamantane is an interesting substrate as the ratio of oxidation at the secondary versus the tertiary C-H bonds is used as a measure of radical versus nonradical oxidation pathways. Industrial processes for the oxidation of cyclohexane, to a mixture of cyclohexanol and cyclohexanone, generally involve low conversions (under 10%). Even at such low conversions, selectivities are modest (70-80%) and substantial amounts of overoxidation products, mostly dicarboxylic acids, are formed. 

The cyclic ketones on treatment with an alkaline or acidic KMn04 give dicarboxylic acid. Adipic acid is commercially prepared by the oxidation of cyclohexanone. The oxidizing agent attacks on an enol form. 

A number of reactions of metal salts can be rationalized in terms of the formation of a carbanion adjacent to the carboxylate. Dibasic metals such as calcium bring two carboxylate units close to each other so that the carbanion formed adjacent to one carboxylate may attack the carbonyl of the other. Thus pyrolysis of calcium acetate affords propanone (acetone) (Scheme 3.62). A similar reaction is found in the pyrolytic cyclization of some dicarboxylic acid anhydrides. Heating Cg and dicarboxylic acids gives cyclopentanones and cyclohexanones... 

Despite problems with acyclic ketones, the reaction is quite useful for cyclic ketones and the corresponding secondary alcohols, the dicarboxylic acid being prepared in good yield. The formation of adipic acid from cyclohexanone (shown above) is an important industrial procedure. Acid dichromate and permanganate are the most common oxidizing agents, although autoxidation (oxidation with... 

The industrially important oxidation of alicyclic ketones to dicarboxylic acids (e. g., cyclohexanone to adipic acid) with oxygen has been successfully carried out. A solid/liquid system was used in the presence of catalytic amounts of PEG-400 and rhenium carbonyl [105]. The absence of one of the catalysts drastically decreases the yield. 

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