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Ethyl acetate, from oxidation

Oxidation of the dibutylstannylene acetal derived from 3-0-benzyl-l,2-0-isopropylidene-a-D-glucofuranose (26) with NBS was finished within 5 min. The eluant for column separation was the mixture of hexane and ethyl acetate (from 4 1 to 2 1). Evaporation of solvent from the corresponding fractions afforded 27 (280 mg, 90%). Colorless crystals were obtained from ethyl acetate-hexane mp 117-118°C [ )D -114.5° (c 1.00, chloroform) IR (Nujol) 3491 cm" (OH), 1725 cm"1 (C=0), C-NMR (CDa3,62.90 MHz) 8 208.2 (C-5). [Pg.81]

With the powerful formylation reagent IV -diformylacetamide imides are obtained from amides or lactams in good yield (equation 56). Oxidation reactions also have found some application in the synthesis of imides. For example, catalytic amounts of ruthenium tetroxide and 10% aqueous NaI04 as cooxidant in an optimized reaction medium (ethyl acetate-water) oxidize acyclic amides to imides. The reaction rate is inversely related to the electron-withdrawing power of the acyl group, i.e. the electron density at the nitrogen atom (equation 57). [Pg.410]

Thus the homologation reaction can be used, for example, for the synthesis of acetaldehyde from methanol [48], propionic acid from acetic acid [47], or ethyl acetate from methyl acetate [50]. Styrene may be produced from toluene by oxidation to benzyl alcohol [51] and homologation to 2-phenylethanol, which in turn can be dehydrated to styrene. From the chemical point of view, the applications of homologation reactions are broad and useful. But, as mentioned before, low selec-... [Pg.1035]

Arsenite is known to have some effect on oxidative phosphorylation. However, as can be seen [Figure 5c] the use of an uncoupler of oxidative phosphorylation (2,l(-dinitrophenol) did not affect accumulation of ethyl acetate. From this it would appear that the main inhibitory effect of arsenite on ethyl acetate accumulation by C. utllls is at the level of acetyl-CoA formation. Thus acetyl-CoA is implicated as a key precursor for synthesis of ethyl acetate supporting a model presented earlier [Figure it]. [Pg.260]

The starting material for iloprost is the enantiomerically pure Corey lactone, which is treated with the lithium salt of ethyl acetate. After oxidation, treatment with l,5-diazabicyclo[4.3.0]non-5-ene (DBN) leads to an exceptionally interesting rearrangement. Presumed cleavage of the cyclic ether generates an enolate, which adds to the cyclopentenone in a Michael reaction. Decarbethoxylation is achieved with l,5-diazabicyclo[2.2.2]octane (DABCO), and the w-chain is constructed under Horner-Wadsworth-Emmons conditions. The subsequent reduction leads to a mixture of allyl alcohols, which can be purified by chromatography, and the alcohol from the less polar product then be released by trans-esterification. Both alcohol functions are then protected as THP-ethers. The... [Pg.358]

A cobalt-impregnated, copper-zinc oxide on alumina catalyst has been reported for the carbonylation of ethanol to ethyl acetate (74). A catalyst comprising CuO-ZnO-Al20s impregnated with Co(NOs)2 was found to be more active toward formation of ethyl acetate from ethanol and carbon monoxide, in comparison with an analogous catalyst in the absence of Co. The use of Re was also reported. [Pg.584]

Place a solution of 10 -4 g. of benzalacetophenone, m.p. 57° (Section IV,130) in 75 ml. of pure ethyl acetate (Section 11,47,15) in the reaction bottle of the catalytic hydrogenation apparatus and add 0 2 g. of Adams platinum oxide catalyst (for full experimental details, see Section 111,150). Displace the air with hydrogen, and shake the mixture with hydrogen until 0 05 mol is absorbed (10-25 minutes). Filter oflF the platinum, and remove the ethyl acetate by distillation. RecrystaUise the residual benzylacetophenone from about 12 ml. of alcohol. The yield of pure product, m.p. 73°, is 9 g. [Pg.734]

Acetaldehyde, first used extensively during World War I as a starting material for making acetone [67-64-1] from acetic acid [64-19-7] is currendy an important intermediate in the production of acetic acid, acetic anhydride [108-24-7] ethyl acetate [141-78-6] peracetic acid [79-21 -0] pentaerythritol [115-77-5] chloral [302-17-0], glyoxal [107-22-2], aLkylamines, and pyridines. Commercial processes for acetaldehyde production include the oxidation or dehydrogenation of ethanol, the addition of water to acetylene, the partial oxidation of hydrocarbons, and the direct oxidation of ethylene [74-85-1]. In 1989, it was estimated that 28 companies having more than 98% of the wodd s 2.5 megaton per year plant capacity used the Wacker-Hoechst processes for the direct oxidation of ethylene. [Pg.48]

Butane-Naphtha Catalytic Liquid-Phase Oxidation. Direct Hquid-phase oxidation ofbutane and/or naphtha [8030-30-6] was once the most favored worldwide route to acetic acid because of the low cost of these hydrocarbons. Butane [106-97-8] in the presence of metallic ions, eg, cobalt, chromium, or manganese, undergoes simple air oxidation in acetic acid solvent (48). The peroxidic intermediates are decomposed by high temperature, by mechanical agitation, and by action of the metallic catalysts, to form acetic acid and a comparatively small suite of other compounds (49). Ethyl acetate and butanone are produced, and the process can be altered to provide larger quantities of these valuable materials. Ethanol is thought to be an important intermediate (50) acetone forms through a minor pathway from isobutane present in the hydrocarbon feed. Formic acid, propionic acid, and minor quantities of butyric acid are also formed. [Pg.68]

Aminophenol. This compound forms white plates when crystallized from water. The base is difficult to maintain in the free state and deteriorates rapidly under the influence of air to pink-purple oxidation products. The crystals exist in two forms. The a-form (from alcohol, water, or ethyl acetate) is the more stable and has an orthorhombic pyramidal stmcture containing four molecules per unit cell. It has a density of 1.290 g/cm (1.305 also quoted). The less stable P-form (from acetone) exists as acicular crystals that turn into the a-form on standing they are orthorhombic bipyramidal or pyramidal and have a hexamolecular unit (15,16,24) (see Tables 3—5). [Pg.309]

Bromobenzaldehyde has been prepared by the oxidation of -bromotoluene with chromyl chloride/ by saponification of the acetal from />-bromophenylmagnesium bromide and orthoformic ester/ by the oxidation of ethyl -bromobenzyl ether with nitric acid/ by the oxidation of /j-bromobenzyl bromide with lead nitrate/ and by the hydrolysis of i-bromobenzal bromide in the presence of calcium carbonate. ... [Pg.22]

Dihydrocholesterol has been prepared by the reduction of cholestenone with sodium and amyl alcohoP and by the hydrogenation of cholesterol. In the presence of platinum black or platinum oxide, yields varying from 6.5 per cent to 40 per cent have been obtained in ether, acetone, ethyl acetate, and acetic acid. ... [Pg.47]

The 4-hydroxy-2-methylindole (MP 112°C to 115°C from benzene/ethyl acetate), used as starting material, may be obtained by hydrogenation of 4-banzyloxy-2-dimethylamino-methylindole (MP 117°C to 120°C from benzene) in the presence of a palladium catalyst (5% on aluminum oxide). [Pg.939]

The ethyl acetate solution is then washed with water, dried and evaporated. To remove any selenium still present, the residue is dissolved in 200 cc of methanol and mixed with 100 g of iron powder and 2 g of active carbon. The mixture is heated for 30 minutes with stirring under reflux, then filtered with suction, washed with methanol and the solution evaporated in vacuo. The residue is then chromatographed on 900 g of aluminum oxide. The residues of the evaporated benzene and ether fractions are treated with active carbon in methanol or acetone, evaporated again, and the residue recrystallized from a mixture of acetone and ether. There are obtained 17.5 g of pure 1-dehydro-17a-methyl-testosterone which melts at 163° to 164°C. [Pg.968]

A solution of 20.8 g. (0.1 mole) of benzalacetophenone (Note 1) (Org. Syn. 2, 1) in 150 cc. of c.p. ethyl acetate (Note 2) is placed in the reaction bottle of the catalytic reduction apparatus (p. 10) and 0.2 g. of platinum oxide catalyst (p. 92) is added. The apparatus is evacuated, then filled with hydrogen, and the mixture shaken with hydrogen until 0.1 mole has been absorbed. The time required is usually about fifteen to twenty-five minutes (Note 3). The platinum is filtered off and the solvent removed from the filtrate by distillation. The benzylacetophenone is recrystallized from about 25 cc. of alcohol and melts at 72-730. The yield is 17-20 g. (81-95 per cent of the theoretical amount). [Pg.36]

In the above-mentioned reactions with hydrazine and hydroxylamine, the actual reducing species is diimide (NH=NH), which is formed from N2H4 by the oxidizing agent and from NH2OH by the ethyl acetate.The rate of this reaction has been studied.Although both the syn and anti forms of diimide are produced, only the syn form reduces the double bond, at least in part by a cyclic mechanism ... [Pg.1007]


See other pages where Ethyl acetate, from oxidation is mentioned: [Pg.355]    [Pg.1257]    [Pg.470]    [Pg.68]    [Pg.94]    [Pg.381]    [Pg.436]    [Pg.360]    [Pg.409]    [Pg.228]    [Pg.280]    [Pg.512]    [Pg.729]    [Pg.119]    [Pg.240]    [Pg.243]    [Pg.249]    [Pg.133]    [Pg.727]    [Pg.911]    [Pg.1208]    [Pg.771]    [Pg.429]    [Pg.807]    [Pg.429]    [Pg.111]    [Pg.112]    [Pg.178]    [Pg.53]    [Pg.486]    [Pg.111]   
See also in sourсe #XX -- [ Pg.2 , Pg.470 ]




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Acetal from

Acetalization-oxidation

Acetals oxidation

Acetate oxidation

Acetic from oxidation

Acetic oxide

Ethyl from oxidation

Ethyl oxidation

Ethyl oxide

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