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Ketones manganese acetate

The main by-products are formic acid, ethanol, methanol, acetaldehyde, acetone, and methylethyl ketone (MEK). When manganese acetate is used as a catalyst, more formic acid (=25%) is obtained at the expense of acetic acid. [Pg.175]

The liquid-phase oxidation (LPO) of light saturated hydrocarbons yields acetic acid and a spectrum of coproduct acids, ketones, and esters. Although propane and pentanes have been used, n-butane is the most common feedstock because it can ideally yield two moles of acetic acid. The catalytic LPO process consumes more than 500 million lb of n-butane to produce about 500 million lb of acetic acid, 70 million lb of methyl ethyl ketone, and smaller amounts of vinyl acetate and formic acid. The process employs a liquid-phase, high-pressure (850 psi), 160-180°C oxidation, using acetic acid as a diluent and a cobalt or manganese acetate catalyst. [Pg.384]

Enols are more reactive than ketones and acids accelerate enolization of ketones. Therefore, in the presence of acids and oxidizing ions, oxidation of ketone proceeds via its enolic form. Kooymen and coworkers [171,172] have found that, at 130° C in the presence of manganese acetate, acetophenone oxidizes in acetic and butyric acids at a rate equal to that of enolization. A linear dependence of log k on a (p = —0.7) was observed for the oxidation of a number of substituted acetophenones. The proposed mechanism is... [Pg.167]

The ketone/alcohol oil was then oxidized further to adipic acid in a 60% nitric acid solution with an ammonium metavanadate/copper nitrate catalyst at 50°-80°C. Selectivity to adipic acid was more than 95%. A second air oxidation process at 80°-85°C and 6 bar has since been developed. By using a copper ace-tate/manganese acetate catalyst in acetic acid solution, the process has the advantage of avoiding the use of the strongly corrosive nitric acid ... [Pg.285]

Vicinal glycols may be oxidized to the corresponding 17a-hydroxy-20-ketones in reasonable yields by means of chromium trioxide in dimethylfor-mamide in the presence of manganese dichloride, or by treatment with dimethyl sulfoxide-acetic anhydride. ... [Pg.184]

Pyrazolines can also be prepared by the oxidation of pyrazolidines. 2-Pyrazolines, which are readily obtained in the reaction of a,j -unsaturated ketones with hydrazine, also undergo nitrogen extrusion at elevated temperature usually in the presence of a basic catalyst. The reaction is believed to proceed via 1-pyrazolines. Treatment of 3,3,5-trialkyl-2-pyrazolines with lead tetraacetate followed by thermolysis affords cyclopropyl acetates ". Oxidation of certain 2-pyrazolines with manganese dioxide gives 3H-pyrazoles, which in turn produce cyclopropenes in the photolysis (equation 7). ... [Pg.311]

The most important applications of peroxyacetic acid are the epoxi-dation [250, 251, 252, 254, 257, 258] and anti hydroxylation of double bonds [241, 252, the Dakin reaction of aldehydes [259, the Baeyer-Villiger reaction of ketones [148, 254, 258, 260, 261, 262] the oxidation of primary amines to nitroso [iJi] or nitrocompounds [253], of tertiary amines to amine oxides [i58, 263], of sulfides to sulfoxides and sulfones [264, 265], and of iodo compounds to iodoso or iodoxy compounds [266, 267] the degradation of alkynes [268] and diketones [269, 270, 271] to carboxylic acids and the oxidative opening of aromatic rings to aromatic dicarboxylic acids [256, 272, 271, 272,273, 274]. Occasionally, peroxyacetic acid is used for the dehydrogenation [275] and oxidation of aromatic compounds to quinones [249], of alcohols to ketones [276], of aldehyde acetals to carboxylic acids [277], and of lactams to imides [225,255]. The last two reactions are carried out in the presence of manganese salts. The oxidation of alcohols to ketones is catalyzed by chromium trioxide, and the role of peroxyacetic acid is to reoxidize the trivalent chromium [276]. [Pg.12]


See other pages where Ketones manganese acetate is mentioned: [Pg.68]    [Pg.308]    [Pg.323]    [Pg.68]    [Pg.400]    [Pg.68]    [Pg.1168]    [Pg.331]    [Pg.354]    [Pg.354]    [Pg.20]    [Pg.250]    [Pg.511]    [Pg.923]    [Pg.1531]    [Pg.148]    [Pg.226]    [Pg.27]    [Pg.173]    [Pg.386]    [Pg.710]    [Pg.424]    [Pg.1028]    [Pg.275]    [Pg.150]    [Pg.62]    [Pg.89]    [Pg.744]    [Pg.14]    [Pg.424]    [Pg.59]    [Pg.26]    [Pg.972]    [Pg.1101]    [Pg.1753]    [Pg.1755]    [Pg.1758]    [Pg.1762]   
See also in sourсe #XX -- [ Pg.381 ]




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