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Acidity, alcohols and

Thalliumilll) niirate, T1(N03)3,3H20. Formed Tl plus cone. HNO,. Immediately hydrolysed by water but is soluble in dilute mineral acids, alcohols and diglyme. Used in oxythallation. ... [Pg.392]

In addition to the preparation of l-alkenes, the hydrogenolysis of allylic compounds with formate is used for the protection and deprotection of carboxylic acids, alcohols, and amines as allyl derivatives (see Section 2.9). [Pg.368]

At the other end of the reaction, deviations from idealized rate laws are attributed to secondary reactions such as degradations of acids, alcohols, and amines through decarboxylation, dehydration, and deamination, respectively. The step-growth polymers which have been most widely studied are simple... [Pg.287]

Acryflc acid, alcohol, and the catalyst, eg, sulfuric acid, together with the recycle streams are fed to the glass-lined ester reactor fitted with an external reboiler and a distillation column. Acrylate ester, excess alcohol, and water of esterification are taken overhead from the distillation column. The process is operated to give only traces of acryflc acid in the distillate. The bulk of the organic distillate is sent to the wash column for removal of alcohol and acryflc acid a portion is returned to the top of the distillation column. If required, some base may be added during the washing operation to remove traces of acryflc acid. [Pg.154]

Infrared Spectroscopy (ir). Infrared curves are used to identify the chemical functionality of waxes. Petroleum waxes with only hydrocarbon functionality show slight differences based on crystallinity, while vegetable and insect waxes contain hydrocarbons, carboxyflc acids, alcohols, and esters. The ir curves are typically used in combination with other analytical methods such as dsc or gc/gpc to characterize waxes. [Pg.318]

Chirazymes. These are commercially available enzymes e.g. lipases, esterases, that can be used for the preparation of a variety of optically active carboxylic acids, alcohols and amines. They can cause regio and stereospecific hydrolysis and do not require cofactors. Some can be used also for esterification or transesterification in neat organic solvents. The proteases, amidases and oxidases are obtained from bacteria or fungi, whereas esterases are from pig liver and thermophilic bacteria. For preparative work the enzymes are covalently bound to a carrier and do not therefore contaminate the reaction products. Chirazymes are available form Roche Molecular Biochemicals and are used without further purification. [Pg.520]

Ameisen-. formic, -aldehyd, n. formaldehyde. -amylMther, -amylester, m. amyl formate, -ather, m. formic ether (ethyl formate), geist, m. (Pharm.) spirit of ants (a mixture of formic acid, alcohol and water), -naphta, n. = Ameisenather. -persaure, /. peroxy-formic acid, performic acid, ameisensauer, a. of or combined with formic acid, formate of. — ameisensaures Salz, formate. [Pg.20]

The Frumkin isotherm can be regarded as a general isotherm from which both the Temkin and Langmuir isotherms can be obtained as special cases. Szklarska-Smialowski and Wieczorek found that the adsorption of various aliphatic compounds (acids, alcohols and amines) on steel in H2SO4 conformed with the Frumkin isotherm. [Pg.1189]

Slater JH, AT Bull, DJ Hartman (1997) Microbial dehalogenation of halogenated alkanoic acids, alcohols and alkanes. Adv Microbial Physiol 38 133-174. [Pg.376]

Hydrogenolysis of esters to aldehydes or alcohols needs high temperatures and high pressures. Moreover, it leads to the formation of acids, alcohols, and hydrocarbons. In contrast, bimetallic M-Sn alloys (M = Rh, Ru, Ni) supported on sihca are very selective for the hydrogenolysis of ethyl acetate into ethanol [181]. For example while the selectivity to ethanol is 12% with Ru/Si02, it increases up to 90% for a Ru-Sn/Si02 catalyst with a Sn/Ru ratio of 2.5 [182]. In addition, the reaction proceeds at lower temperatures than with the classical catalysts (550 K instead of temperatures higher than 700 K). The first step is the coordination of the ester to the alloy (Scheme 46), and most probably onto the tin atoms. After insertion into the M - H bond, the acetal intermediate decomposes into acetaldehyde and an ethoxide intermediate, which are both transformed into ethanol under H2. [Pg.203]

Alcohols, Cj-Cg carboxylic acids, alcohols and sulfur gases. [Pg.108]

The reaction of a carboxylic acid with N,Af -carbonyldiimidazolellH33 (abbreviated as CDI), forming an imidazolide as the first step followed by alcoholysis or phenolysis of the imidazolide (second step), constitutes a synthesis of esters that differs from most other methods by virtue of its particularly mild reaction conditions.t41,[5] It may be conducted in two separate steps with isolation of the carboxylic acid imidazolide, but more frequently the synthesis is carried out as a one-pot reaction without isolation of the intermediate. Equimolar amounts of carboxylic acid, alcohol, and CDI are allowed to react in anhydrous tetrahydrofuran, benzene, trichloromethane, dichloromethane, dimethylformamide, or nitromethane to give the ester in high yield. The solvents should be anhydrous because of the moisture sensitivity of CDI (see Chapter 2). Even such unusual solvent as supercritical carbon dioxide at a pressure of 3000 psi and a temperature of 36-68 °C has been used for esterification with azolides.[6]... [Pg.39]

Since the imidazolide method proceeds almost quantitatively, it has been used for the synthesis of isotopically labeled esters (see also Section 3.2), and it is always useful for the esterification of sensitive carboxylic acids, alcohols, and phenols under mild conditions. This advantage has been utilized in biochemistry for the study of transacylating enzymes. A number of enzymatic transacylations (e.g., those catalyzed by oc-chymo-trypsin) have been shown to proceed in two steps an acyl group is first transferred from the substrate to the enzyme to form an acyl enzyme, which is then deacylated in a second step. In this context it has been shown[21] that oc-chymotrypsin is rapidly and quantitatively acylated by Af-fraw.s-cinnamoylimidazole to give /ra/w-cinnamoyl-a-chymotrypsin, which can be isolated in preparative quantities and retains its enzymatic activity (see also Chapter 6). [Pg.42]

One of the main problems of the pyrolysis technique is related to the low volatility of pyrolysis products arising from natural and some synthetic macromolecules. In fact, the polar acidic, alcoholic and aminic moieties are not really suitable for gas chromatographic analysis. Their poor volatility and their polarity cause a rather low reproducibility of the pyrograms, low sensitivity for specific compounds, and strong memory effects. Memory effects need to be borne in mind when the pyrolysis of polar molecules is performed. Polar pyolysis products may not be completely eluted by the gas chromatographic column, and... [Pg.304]

Potassium iodate is a fairly strong oxidizing agent that may be used in the assay of a number of pharmaceutical substances, for instance benzalkonium chloride, cetrimide, hydralazine hydrochloride, potassium iodide, phenylhydrazine hydrochloride, semicarbazide hydrochloride and the like. Under appropriate experimental parameters the iodate reacts quantitatively with both iodides and iodine. It is, however, interesting to observe here that the iodate titrations may be carried out effectively in the presence of saturated organic acids, alcohol and a host of other organic substances. [Pg.219]

Hydrogen bond donor solvents are simply those containing a hydrogen atom bound to an electronegative atom. These are often referred to as protic solvents, and the class includes water, carboxylic acids, alcohols and amines. For chemical reactions that involve the use of easily hydrolysed or solvolysed compounds, such as AICI3, it is important to avoid protic solvents. Hydrogen bond acceptors are solvents that have a lone pair available for donation, and include acetonitrile, pyridine and acetone. Kamlet-Taft a and ft parameters are solvatochromic measurements of the HBD and HBA properties of solvents, i.e. acidity and basicity, respectively [24], These measurements use the solvatochromic probe molecules V, V-die lliy I -4-n i in tan iline, which acts as a HBA, and 4-nitroaniline, which is a HBA and a HBD (Figure 1.17). [Pg.24]

More recent developments in the field of the Pirkle-type CSPs are the mixed r-donor/ r-acceptor phases such as the Whelk-Of and the Whelk-02 phases.The Whelk-Of is useful for the separation of underiva-tized enantiomers from a number of families, including amides, epoxides, esters, ureas, carbamates, ethers, aziridines, phosphonates, aldehydes, ketones, carboxylic acids, alcohols and non-steroidal anti-inflammatory drugs.It has been used for the separation of warfarin, aryl-amides,aryl-epoxides and aryl-sulphoxides. The phase has broader applicability than the original Pirkle phases. The broad versatility observed on this phase compares with the polysaccharide-derived CSPs... [Pg.464]

Bell, G.H. Solubilities of normal aliphatic acids, alcohols and alkanes in water, Chem. Phys. Lipids, 10 1-10, 1973. [Pg.25]

Miscible with acetic acid, alcohol, and ether (Hawley, 1981)... [Pg.62]

Soluble in acetic acid, alcohols, and ketones (Windholz et ah, 1983)... [Pg.691]

Compared with tin stannous chloride is only one half as efficient since it furnishes only two electrons per mole (tin donates four electrons). This disadvantage is more than offset by the solubility of stannous chloride in water, hydrochloric acid, acetic acid, alcohols and other organic solvents. Thus reductions with stannous chloride can be carried out in homogeneous media (Procedure 36, p. 214). [Pg.30]

The anaerobic digestion of fatty acids, alcohols and organic compounds is accomplished by a syntrophy between H2-producing and H2-consuming methanogenic archaea [6] that favors the better use of the energy content of primary substrates [7]. [Pg.271]


See other pages where Acidity, alcohols and is mentioned: [Pg.137]    [Pg.395]    [Pg.498]    [Pg.482]    [Pg.988]    [Pg.116]    [Pg.134]    [Pg.794]    [Pg.1282]    [Pg.279]    [Pg.50]    [Pg.50]    [Pg.67]    [Pg.341]    [Pg.1689]    [Pg.14]    [Pg.329]    [Pg.252]    [Pg.811]    [Pg.55]    [Pg.56]    [Pg.318]    [Pg.16]    [Pg.22]    [Pg.361]    [Pg.366]    [Pg.383]   
See also in sourсe #XX -- [ Pg.603 ]

See also in sourсe #XX -- [ Pg.603 ]

See also in sourсe #XX -- [ Pg.505 , Pg.506 ]

See also in sourсe #XX -- [ Pg.624 , Pg.625 ]




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Acidity alcohols and phenols

Acidity and Basicity of Alcohols

Acidity of Alcohols and Phenols

Acidity, alcohols and amines

Acids and Bases in Alcohol-Water Mixtures

Alcohols and Olefins in Strong Bronsted Acids

Alcohols and acid anhydrides

Alcohols as acids and bases

Alcohols carboxylic acids and

Alcohols, Ethers and Carboxylic Acid Esters

Alcohols, Phenols and Carboxylic Acids as Asymmetric Organocatalysts

Alcohols, Phenols, and Carboxylic Acids

Aldehydes, Ketones, Alcohols, and. Carboxylic Acids

Benzoic acid and benzyl alcohol from benzaldehyde

Benzyl alcohol and benzoic acid (Cannizzaro reaction)

Carboxylic Acids and Derivatives to Alcohols

Esterification of carboxylic acids and alcohols

Esters from carboxylic acid and alcohol

Esters of Araliphatic Alcohols and Aliphatic Acids

Ethyl acetate from acetic acid and alcohol

FROM CARBOXYLIC ACID AND ALCOHOLS

Fatty Acids, Alcohols, and Esters

Fatty acids and alcohols

Fatty acids and esters of monohydric alcohols

Furfuryl alcohol and furoic acid

Gas phase acidity of alcohols and phenols

Hydrogenation of Acids and Esters to the corresponding Alcohols

Inductive effect alcohol acidity and

Kinetic Resolution of Alcohols, Amines, and Amino Acids

Organic alcohols and acids

Oxidation of Alcohols to Aldehydes and Acids

Oxidation of Alcohols to Aldehydes, Ketones, and Carboxylic Acids

Oxidation of alcohols and aldehydes to carboxylic acids

Photoaddition of Water, Alcohols, and Carboxylic Acids

Reaction CV.—Action of Acid Anhydrides on Alcohols and Phenols

Recovery of Methanol and Acetic Acid in Poly (Vinyl Alcohol) Production

Solubility of fatty acids and alcohols

Synthesis of Ethers Alcohols and Mineral Acids

Tabulation of Known Acids and Alcohols

The Acidity of Alcohols and Phenols

The Enhanced Acidity of Carboxylic Acids and Enols Relative to Alcohols

Transesterification polylactic acid and allyl alcohol

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