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Aqueous acetic acid

To prepare acetic acid, aqueous ethanol is added gradually to a hot mixture of aqueous sodium dichromate and sulphuric acid. The oxidising mixture is now always in excess, and therefore the oxidation proceeds as far as possible moreover, the reaction is carried out under reflux, so that any acetaldehyde which volatilises is returned to the oxidising mixture. Hence the final product contains only a small amount of acetaldehyde. [Pg.73]

CF3COOH, H2O, 20°, 48 h, 85-90% yield. The r-butoxymethyl ether is stable to hot glacial acetic acid aqueous acetic acid, 20° and anhydrous trifluoroacetic acid. [Pg.25]

Chlorobenzoic acid [535-80-8] M 156.6, m 154-156°, 158°, dj 1.496, pK 3.82 (5.25 in 50% dimethylacetamide). Crystd successively from glacial acetic acid, aqueous EtOH and pet ether (b 60-80°). It also recrysts from CgH6 or Et20-hexane, and sublimes at 55° in a vacuum. [Anal Chem 26 726 1954] The methyl ester has m 21°, b 231°/atm. The S-benzyl thiouronium salt has m 164-165° (from EtOH) [Acta Chem Scand 9 1425 1955 J Chem Soc 1318 I960],... [Pg.161]

Synthesis of 16,16-dimethyl-trans-A -PGEi 2.35 g of the bis-tetrahydropyranyl ether were dissolved in 6 ml of tetrahydrofuran and 60 ml of 65%-acetic acid aqueous solution and the solution stirred at 60°C to 70°C for 20 minutes. The reaction mixture was extracted with ethyl acetate, and the organic layer was washed with water, dried and concentrated under reduced pressure. The residue was purified by column chromatography on silica gel using ethyl acetate-cyclohexane (2 3) as eluent to yield 270 mg of the title compound. [Pg.719]

H2CO3 (carbonic acid) aqueous phase HC2H3O2 (acetic acid) aqueous, gas phases HCHOz (formic acid) aqueous, gas phases H2C2O4 (oxalic acid) aerosol particles solid phase RCCX3H (many carboxylic acids)... [Pg.423]

Caution is advised [1] to prevent explosions when using an analytical method involving sequential addition of acetic acid, aqueous 4-toluenesulfonic acid and acetic anhydride to serum [2], It is difficult to see why this should happen, unless the anhydride were all added before the sulfonic acid solution. [Pg.523]

Figure 1. Arrhenius plot of D1 thermal decomposition in a 50 wt% acetic acid aqueous solution. Figure 1. Arrhenius plot of D1 thermal decomposition in a 50 wt% acetic acid aqueous solution.
In the foregoing calculation of Asin//(1) and Asin//(3), we have used the tabulated values for the standard enthalpies of formation of ethanol and acetic acid aqueous solutions. This looks sensible (after the definitions given in section 2.3), because the standard states of ethanol and acetic acid solutions in water correspond to 1 mol of C2H5OH or CH3COOH in about... [Pg.18]

There are extensive data for the acid-catalyzed protiodesilylation of XCgELrSiMes in methanol-aqueous perchloric acid or acetic acid-aqueous sulphuric acid at 50°C225. Correlation analysis of the partial rate factors (relative rate constants) by means of the Yukawa-Tsuno equation (Section n.B) finds p = —5.3 and r+ = 0.65. These values are consistent with a relatively low demand for stabilization of the transition state by electron delocalization, i.e. the transition state is early along the reaction coordinate, p-NO2 is highly deactivating with / = 14 x 10 but 0-NO2 is even more deactivating, with / = 6.8 x 10-5. This contrasts with the deactivation order discussed above for nitration and chlorination (Table 6), and may be explained in terms of the early transition state, well removed from the Wheland intermediate. [Pg.513]

Synonyms Acetasol Acetic acid (aqueous solution) AcOH AI3-02394 BRN 0506007 CCRIS 5952 EINECS 200-580-7 Ethanoic acid Ethylic acid FEMA No. 2006 Glacial acetic acid HAc Methane-carboxylic acid NSC 132593 Pyroligneous acid UN 2789 UN 2790 Vinegar acid Vosol. [Pg.58]

Acetamidofluorene, see 2-Acetylaminofluorene 2-Acetaminofluorene, see 2-Acetylaminofluorene Acetanhydride, see Acetic anhydride Acetasol, see Acetic acid Acetdimethylamide, see A,A-Dimethylacetamide Acetic acid, amyl ester, see Amyl acetate Acetic acid anhydride, see Acetic anhydride Acetic acid (aqueous soln), see Acetic acid Acetic acid, 2-butoxy ester, see sec-Butyl acetate Acetic acid, butyl ester, see Butyl acetate Acetic acid, sec-butyl ester, see sec-Butyl acetate Acetic acid, ferf-butyl ester, see ferf-Butyl acetate Acetic acid dimethylamide, see A,A-Dimethylacetamide Acetic acid, 1,3-dimethylbutyl ester, see sec-Hexyl acetate Acetic acid, 1,1-dimethylethyl ester, see ferf-Butyl acetate Acetic acid, ethenyl ester, see Vinyl acetate... [Pg.1456]

Some reagents are milder and less powerful oxidants and have been used to oxidize arylamines to the corresponding nitroso compounds. These include 30 % hydrogen peroxide in acetic acid, ° aqueous solutions of potassium permanganate, and alkaline hypochlorite amongst others. The hypochlorite oxidation of arylamines containing o-nitro substiffients is reported to yield benzofuroxans. For a discussion of the synthesis of aromatic nitroso compounds the readers are directed to a review by Boyer. ... [Pg.155]

The synthesis of a water-soluble diphenylmethano-bridged fullerene 122 was achieved by hydrolyzing the bis (acetamide) 121 with acetic acid-aqueous hydrochloric acid and then converting it into the bis(succinamide) 122 by treatment with succinic anhydride (Scheme 4.25) [158]. Compound 122 is soluble in water at pH > 7. This is an important requirement for the investigation of the biological activity of fullerenes. Remarkably, 122 is an inhibitor for the HIV enzymes protease (HIV-P) and reverse transcriptase (HIV-RT) [159]. As suggested by molecular modeling. [Pg.125]

Solid esters are easily crystallisable materials. It is important to note that esters of alcohols must be recrystallised either from non-hydroxylic solvents (e.g. toluene) or from the alcohol from which the ester is derived. Thus methyl esters should be crystallised from methanol or methanol/toluene, but not from ethanol, n-butanol or other alcohols, in order to avoid alcohol exchange and contamination of the ester with a second ester. Useful solvents for crystallisation are the corresponding alcohols or aqueous alcohols, toluene, toluene/petroleum ether, and chloroform (ethanol-free)/toluene. Carboxylic acid esters derived from phenols are more difficult to hydrolyse and exchange, hence any alcoholic solvent can be used freely. Sulphonic acid esters of phenols are even more resistant to hydrolysis they can safely be crystallised not only from the above solvents but also from acetic acid, aqueous acetic acid or boiling n-butanol. [Pg.57]

Reaction of AT-fluorobis(trifluoromethylsulfonyl)amine (Id) with alkenes gives various products, depending on the reaction conditions and the structure of the substrate. In solvents of higher nucleophilicity such as water, acetic acid, aqueous hydrochloric acid, and 70 % hydrogen fluoride/pyridine, a-fluorohydrins or their acetates, a-chloro-fl-fluoroalkanes or a,/ -difluoroal-kanes, e.g. 14. are obtained.146 Reaction of styrene and ( >l-phenylpropene with Id in dich-loromethane/acetic acid gives l-acetoxy-2-fluoro-l-phenylethane and -propane, in 92 and 99 % yield, respectively, the latter product in a ratio (erythrojthreo) 1 l.146... [Pg.483]

Discussion In principle, acetals are cleaved by acid-catalyzed hydrolysis. In most cases aqueous acetic acid, aqueous trifluoracetic acid, dilute HC1 in THF or DOWEX 50W (H+) resin are used. Thus, treatment of 6 with DOWEX ion exchange resin in methanol rapidly furnishes the corresponding 1,2-diol without any further chromatographic purification steps. Generally, polymer supported reagents benefit from the ease of removal from the reaction mixture just by filtration of the insoluble resin. The resulting diol is acetylated by addition of acetic anhydride and pyridine. Final acetal exchange is achieved by acetic anhydride and catalytic amounts of concentrated sulfuric acid. A mixture (2 1) of anomers is obtained. [Pg.200]

Volatile oils, glacial acetic acid, aqueous fixed alkali hydroxide solution and aqueous alkali Soluble [1,4]... [Pg.158]

Architecture of Hydrates and Local Structure of Acetic Acid Aqueous Solution Ab Initio Calculations and Car-Parrinello Molecular Dynamics (CPMD) Simulations on Hydrogen-Bonding Rings, Network, and Intra-Hydrate Protonation in Multi-Hydrates of Acetic Acid Monomer... [Pg.271]

Both the experimental and theoretical studies indicate that the interactions between acetic acid and water molecules are more competitive in dilute aqueous solution. However to our knowledge, the specific interactions between acetic acid and water molecules are still not well understood, especially in such as the nature of hydrogen bonding, the bonds networking, the rule in architecture of larger hydration compounds, deprotonation of acetic acid in solution, stability of the hydrated proton, the local structure of its aqueous solution, and so on. In the present work, we have performed ab initio calculations on multi-hydrates (rich water hydration compounds) of acetic acid, and ab initio Car-Parrinello molecular dynamics (CPMD) [20] simulations on acetic acid monomer and water system (at dilute aqueous solution condition) to find something helpful for interpreting the nature of acetic acid aqueous solution. [Pg.274]

Let us now consider Scheppele s discussion of the solvolysis of 2-d-exo- and -endo-bicyclo[2.2.1] hept-2-yl p-nitrobenzoates and p-toluenesulfonates. A maximum a isotope effect of 1 22 is suggested for kH/kD for the limiting solvolysis of simple secondary sulphonates (solvolyses where the rate is not affected by the nucleophilicity of the medium). The endo-esters yield a similar value which might be taken to imply the absence of steric hindrance in their reaction. However, whereas the maximum isotope effect for the simple sulphonates is believed to arise partly from an activated complex in the conversion of the internal ion pair into a solvent-separated ion pair, B - C, the effect in the endo-norbomyl compounds is suggested to arise during the transition state involved in the formation of the intimate ion pair, A - B. The latter is deduced from the fact that polarimetric and titrimetric rate constants are the same in acetic acid, aqueous acetone and ethanol (Winstein and Trifan, 1949 and 1952). If this is the case, the endo-effect of 1-20 should be... [Pg.191]

Plant Alkaloids Poppy Papaver somniferum 5% Acetic acid aqueous 10 [37]... [Pg.83]


See other pages where Aqueous acetic acid is mentioned: [Pg.138]    [Pg.434]    [Pg.65]    [Pg.155]    [Pg.602]    [Pg.271]    [Pg.322]    [Pg.191]    [Pg.342]    [Pg.141]    [Pg.141]    [Pg.63]    [Pg.220]    [Pg.434]    [Pg.94]    [Pg.94]    [Pg.272]    [Pg.273]    [Pg.274]    [Pg.280]    [Pg.294]    [Pg.229]    [Pg.5]   
See also in sourсe #XX -- [ Pg.324 ]




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