Methyl alcohol carbonylation

Currently, almost all acetic acid produced commercially comes from acetaldehyde oxidation, methanol or methyl acetate carbonylation, or light hydrocarbon Hquid-phase oxidation. Comparatively small amounts are generated by butane Hquid-phase oxidation, direct ethanol oxidation, and synthesis gas. Large amounts of acetic acid are recycled industrially in the production of cellulose acetate, poly(vinyl alcohol), and aspirin and in a broad array of other... 

Cellobiose was prepared first by Skraup and Konig by the saponification of the octaacetate with alcoholic potassium hydroxide, and the method was improved by Pringsheim and Merkatz.3 Aqueous barium hydroxide also has been employed for the purpose, and methyl alcoholic ammonia has been used extensively for the hydrolysis of carbohydrate acetates. The method of catalytic hydrolysis with a small quantity of sodium methylate was introduced by Zemplen,i who considered the action to be due to the addition of the reagent to the ester-carbonyl groups of the sugar acetate and the decomposition of the addition compound by reaction with alcohol. The present procedure, reported by Zemplen, Gerecs, and Hadacsy, is a considerable improvement over the original method (see Note 2). 

Supplement 1941 1-161 Derivatives. Methyl alcohol, 273. Ethyl alcohol, 292. Ethyl ether, 314. Glycerol, 502. Carbonyl Compounds Aldehydes, Ketones, Ketencs and Derivatives. Formaldehyde, 558. Acetaldehyde, 635. Acetone, 635. Ketene, 724. Hydroxy-Carbonyl Compounds Aldehyde-Alcohols, Ketone-Alcohols, Monosaccharides and Derivatives. Glycolaldehyde, 817. Aldol, 824. Pentoses, 858. Hexoses, 878. 

The oxidative carbonylation of alcohols and phenols to carbonates can be catalyzed by palladium or copper species [154-213]. This reaction is of particular practical importance, since it can be developed into an industrial process for the phosgene-free synthesis of dimethyl carbonate (DMC) and diphenyl carbonate (DPC), which are important industrial intermediates for the production of polycarbonates. Moreover, DMC can be used as an eco-friendly methylation and carbonylation agent [214,215]. The industrial production of DMC by oxidative carbonylation of methanol has been achieved by Enichem [216] and Ube [217]. 

The preparation of acetic acid represents a special case. Olah and coworkers as well as Hogeveen and coworkers have demonstrated that CO can react with methane under superacidic conditions, giving the acetyl cation and by subsequent quenching acetic acid or its derivatives (see Section 7.2.3). Monosubstituted methanes, such as methyl alcohol (or dimethyl ether), can be carbonylated to acetic acid.115 Similarly, methyl halides undergo acid-catalyzed carbonylation.115,116 Whereas the acid-catalyzed reactions can be considered as analogs of the Koch reaction, an efficient Rh-catalyzed carbonylation of methyl alcohol in the presence of iodine (thus in situ forming methyl iodide) was developed by Monsanto and became the dominant industrial process (see Section 7.2.4). 

FIGURE 2 Acetaldehyde manufacture by carbonylation of methyl alcohol (methanol). 

A mixture consisting of 3-[(dipropylamino)carbonyl]benzoic acid (0.21 mmol), l-(3-dimethyl-aminopropyl)-3-ethylcarbodiimide (0.21 mmol), and 1-hydroxy-benzotriazole (0.22 mmol) was dissolved in 2.5 ml DMF, then stirred 1 hour, and treated with the Step 6 product (0.17 mmol) dissolved in 1 ml of DMF. The mixture was stirred 3 days at ambient temperature and was then quenched with 1 M KH2P04. It was then diluted with EtOAc, washed with water, 1 M NaHC03, and brine, dried with Na2S04, and concentrated. The residue was purified by chromatography using 5% methyl alcohol/CH2Cl2 and the product isolated in 51% yield. 

In the presence of dioxygen, the carbon radical R- produced by reactions (201) and (202) ar transformed into alkylperoxy radicals ROO, reacts with Co or Mn species to regenerate th Co " or Mn " oxidants, and produce primary oxygenated products (alcohol, carbonyl compounds which can be further oxidized to carboxylic acids. This constitutes the basis of several Industrie processes such as the manganese-catalyzed oxidation of n-alkenes to fatty acids, and the cobal catalyzed oxidation of butane (or naphtha) to acetic acid, cyclohexane to cyclohexanol-on mixture, and methyl aromatic compounds (toluene, xylene) to the corresponding aromatic monc or di-carboxylic acids. ... 

Cavinato, G. Toniolo, L.J. New aspects of the synthesis of dimethyl carbonate via carbonylation of methyl alcohol promoted by methoxycarbonyl complexes of palladium(II). J. Organomet. Chem. 1993, 444 C65-C66. 

Another type of compound having the furo-furanone skeleton, in which a C—C bond was formed at C-2 of 3, has been achieved by using 3 as a Michael carbanion donor to various a, 3-unsaturated carbonyl compounds. Thus, it gives 94a when combined with methyl vinyl ketone, which can then be converted to the cyclic acetal upon reaction with methyl alcohol in the presence of an acid (83T2137). The reaction was extended to acrolein, a-methyl acrolein, and crotonaldehyde to give 94c. Its application with 2-cyclohexen-l-one required an unexpected acid catalysis to give 94b. On the other hand, extending the reaction to a cyclic enedione,... 

Oxysulfides and mercaptans of carbonyl compounds with the above mentioned mercaptans Methyl alcohol Higher aliphatic alcohols Acetol... 

Chemical/Physical May hydrolyze in aqueous solutions forming methyl alcohol and 3-(((((4-methoxy-6-methyl-l,3,5-triazin-2-yl)amino)carbonyl)amino)sulfonyl)-2-thiophenecarboxylic acid. 

Ethyl oleate was synthesized by the esterification of and ethanol catalyzed by SnCb 2H2O (Cardoso et al., 2008). Under the circumstance of excess ethanol, the effects of the concentration of the catalyst and oleic acid, and temperature on the reaction rate were investigated. A related esterification mechanism was presented and described as follows in presence of Sn2+( SnCh 2H2O) catalyst, the carbonyl of the fatty acid is polarized to activate of substrate, which makes the nucleophilic attack to the molecules by ethanol become more favorable. Cardoso et al. investigated the effect of different carbonic chain of alcohol (methyl alcohol, ethyl alcohol, n-p>ropyl alcohol, n-butyl alcohol) on the conversion of oleic acid into respective ester. The results showed that the conversion rate was down with the increase of carbon chain of alcohol, which indicated that high bulk hindrance occurs on the hydroxyl of the alcohol, and the efficient attack of them to the p>olarized carbonyl of oleic acid is reduced. However, it is not clear how the carbonyl is p>olarized by Sn2+. 

Roth and co-workers [84] at the Monsanto company developed an acetic acid production process by the reaction of methyl alcohol with carbon monoxide in the presence of rhodium carbonyl as the major catalyst. 

As shown in eq. (12.30), levulinic acid ethylester has two kinds of carbonyl ketacarbonyl and estercarbonyl. Me2TiCl2 then selectively reacts with a keto-carbonyl group, and the methylated alcohol esters are prepared in 90% or more yield [83]. 

Acrylic acid and its esters formed by the reaction as shown in eq. (19.39) had been produced until the end of the 1960s. But now they are produced by the oxidation of propene. For the production of acetic acid by the carbonylation of methyl alcohol shown in eq. (19.41), nickel catalysts were at first used, but afterwards the rhodium catalysts as described previously in Chapter 18 have been used. However, even now nickel catalysts are used in the production of propionic acid by the carbonylation of ethylene shown in eq. (19.40) [72]. 

Hexane is a solvent with only hydrogen and carbon atoms and has a 100% nonpolar character, 8, = 14.9. Acetone is a solvent with carbon, hydrogen, and polar carbonyl group. It has a nonpolar 6j = 15.5, a polar 5p = 10.4, and 5 = 7.0. Methyl alcohol is a solvent with nonpolar 6 = 15.1, a polar 8p = 12.3, and S, = 22.3. The percentage of each delta value of the total solubility parameter of the three solvents are ... 

Carbonylation of Alcohols and Esters. The mechanism of ttie Rh/I" catalysed alcohol carbonylation has been studied in detail. Rates decrease sharply from methanol to n-propanol. Formation of isobutyric acid as a by-product points to a p-H elimination-reinsertion sequence.This sequence has also been demonstrated for ethanol carbonylation by selective C labelling (eqn.l8). The reductive carbonylation of methanol in the presence of Col2 and PPhg generates acetaldehyde, ethanol and methyl acetate. Only diphenylether and alkanes as solvents did not decompose under the reaction conditions (17CPC,... 

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