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Acidity, also compounds

The imides, primaiy and secondary nitro compounds, oximes and sulphon amides of Solubility Group III are weakly acidic nitrogen compounds they cannot be titrated satisfactorily with a standard alkaU nor do they exhibit the reactions characteristic of phenols. The neutral nitrogen compounds of Solubility Group VII include tertiary nitro compounds amides (simple and substituted) derivatives of aldehydes and ketones (hydrazones, semlcarb-azones, ete.) nitriles nitroso, azo, hydrazo and other Intermediate reduction products of aromatic nitro compounds. All the above nitrogen compounds, and also the sulphonamides of Solubility Group VII, respond, with few exceptions, to the same classification reactions (reduction and hydrolysis) and hence will be considered together. [Pg.1074]

Carboxylic acid anhydrides compounds of the type RCOCR can also serve as sources of acyl cations and m the presence of aluminum chloride acylate benzene One acyl unit of an acid anhydride becomes attached to the benzene ring and the other becomes part of a carboxylic acid... [Pg.485]

See also pyrophosphorous acid.) [PHOSPHORUS COMPOUNDS] (Vol 18) Diphosphoric(III,V) acid [14902-77-3]... [Pg.333]

Deodorization can be carried out ki batch, continuous, or semicontkiuous systems. Figure 4 shows a typical design for a semicontkiuous deodorizer. The heated ok is passed through a series of trays under vacuum. Steam is passed through the ok through a steam sparge ki the bottom of the tray. Volatiles are carried through the headspace and condensed. In addition to fatty acids and compounds responsible for odor, some tocopherols and sterols are also distilled kito the condensate. The amount of tocopherols distilled depends on deodorization temperature and vacuum. [Pg.127]

Zirconium trifluoride [13814-22-7], ZrP, was first prepared by the fluorination of ZrH2 using a mixture of H2 and anhydrous HP at 750°C (2). It can also be prepared by the electrolysis of Zr metal in KF—NaF melts (3). Zirconium trifluoride is stable at ambient temperatures but decomposes at 300°C. It is slightly soluble in hot water and readily soluble in inorganic acids. This compound is of academic interest rather than of any industrial importance. [Pg.262]

The term naphthenic acid, as commonly used in the petroleum industry, refers collectively to all of the carboxyUc acids present in cmde oil. Naphthenic acids [1338-24-5] are classified as monobasic carboxyUc acids of the general formula RCOOH, where R represents the naphthene moiety consisting of cyclopentane and cyclohexane derivatives. Naphthenic acids are composed predorninandy of aLkyl-substituted cycloaUphatic carboxyUc acids, with smaller amounts of acycHc aUphatic (paraffinic or fatty) acids. Aromatic, olefinic, hydroxy, and dibasic acids are considered to be minor components. Commercial naphthenic acids also contain varying amounts of unsaponifiable hydrocarbons, phenoHc compounds, sulfur compounds, and water. The complex mixture of acids is derived from straight-mn distillates of petroleum, mosdy from kerosene and diesel fractions (see Petroleum). [Pg.509]

In addition to the conventional mixed acids commonly used to produce DNT, a mixture of NO2 and H2SO4 (8), a mixture of NO2 and oxygen (9), and just HNO (10) can also be used. TerephthaUc acid and certain substituted aromatics are more amenable to nitrations using HNO, as compared to those using mixed acids. For compounds that are easily nitratable, acetic acid and acetic anhydride are sometimes added to nitric acid (qv). Acetyl nitrate, which is a nitrating agent, is produced as an intermediate as follows ... [Pg.33]

In addition to the materials shown in Table 1, other organic materials find a minor portion of their use in mbber processing, such as waxes and fatty acids. Also, the mbber industry uses modest amounts of inorganic compounds, notably elemental sulfur, zinc oxide, magnesium oxide, and sodium bicarbonate. [Pg.219]

However, the yields are usuaHy poor because of the oxidation of the Grignard reagent by thaHium(III). Reaction of R3TI with acids also affords a convenient route to this type of compound. [Pg.469]

Methoxy-2-trimethylsilyloxyfuran is also a highly efficient diene under the influence of Lewis acids this compound is substituted readily at position 5 with a wide variety of agents (Scheme 74) (82TL353). [Pg.77]

Numerous variations of this reaction have been studied, principally those involving a prior inclusion of the nuclear sulfur atom in a thioacylamino compound. Thus, thiobenz-amido acetaldehyde diethyl acetal (8) underwent ring closure to 2-phenylthiazole (9) on gentle heating (57JCS1556). Similarly, iV-thioacyl a-amino acids also undergo ready ring closure to thiazoles. [Pg.113]

Bromination of y-dinitrobutanoic acids and base treatment produced 3-nitroisoxazoline A-oxides (Scheme 139) (75MIP41601). Alkylation of the potassium salt of y-dinitro-2-butenoic acid also gave a similar compound (Scheme 139) (74KGS571). [Pg.102]

Alkylperoxy (RO2) and peroxyacyi (RC(O)OO) radicals react with NO to form NO2. The alkylperoxy radicals (RO2) react with NO2 to form pemitric acid-type compounds, which decompose thermally as the temperature increases. The peroxyacyi radical reacts with NO2 to form PAN-type compounds, which also decompose thermally. [Pg.175]

Your company receives toluene, a listed toxic chemical, from another facility, reacts the toluene with air to form benzoic acid, and further reacts the benzoic acid with a cadmium catalyst to form terephthallc acid. Cadmium compounds and terephthallc acid are also listed toxic chemicals. Your company processes toluene, and otherwise uses (not processes) the cadmium catalyst (see the definition of "otherwise use" below). Your company manufactures benzoic acid and terephthallc acid. Benzoic acid, however, is not a listed chemical and thus does not trigger reporting requirements. [Pg.26]

The formation of adducts of enamines with acidic carbon compounds has been achieved with acetylenes (518) and hydrogen cyanide (509,519,520) (used as the acetone cyanohydrin). In these reactions an initial imonium salt formation can be assumed. The addition of malonic ester to an enamine furnishes the condensation product, also obtained from the parent ketone (350,521). [Pg.420]

The term Knoevenagel reaction however is used also for analogous reactions of aldehydes and ketones with various types of CH-acidic methylene compounds. The reaction belongs to a class of carbonyl reactions, that are related to the aldol reaction. The mechanism is formulated by analogy to the latter. The initial step is the deprotonation of the CH-acidic methylene compound 2. Organic bases like amines can be used for this purpose a catalytic amount of amine usually suffices. A common procedure, that uses pyridine as base as well as solvent, together with a catalytic amount of piperidine, is called the Doebner modification of the Knoevenagel reaction. [Pg.176]

In the petrochemical field, hydrogen is used to hydrogenate benzene to cyclohexane and benzoic acid to cyclohexane carboxylic acid. These compounds are precursors for nylon production (Chapter 10). It is also used to selectively hydrogenate acetylene from C4 olefin mixture. [Pg.113]

Despite the above-mentioned short-comings, this approach to the estimation of those deoxy sugars which yield malonaldehyde when oxidized with periodate, seemed promising, since, as has been seen (58,59), the dye is formed quantitatively in the reaction of malonaldehyde with 2-thiobarbituric acid also, more recently, its constitution (49,57) and molar extinction coefficient (36) have been established. Thus, if conditions could be found in which malonaldehyde, while being formed quantitatively from the deoxy sugars, would be stable, an ideal method, independent of standard compounds, would be available for the quantitative determination of all of these sugars. [Pg.106]

Both the malonic ester synthesis and the acetoacetic ester synthesis are easy to cany out because they involve unusually acidic dicarbonyi compounds. As a result, relatively mild bases such as sodium ethoxide in ethanol as solvent can be used to prepare the necessary enolate ions. Alternatively, however, it s also possible in many cases to directly alkylate the a position of monocarbonyl compounds. A strong, stericaliy hindered base such as LDA is needed so that complete conversion to the enolate ion takes place rather than a nucleophilic addition, and a nonprotic solvent must be used. [Pg.861]

The biogenetic scheme for endiandric acids also predicts the plausible existence in nature of endiandric acids E (5), F (6), and G (7). Even though they are still undiscovered, their synthesis has been achieved (Scheme 6). For endiandric acids E and F, key intermediate 24 is converted, by conventional means, to aldehyde 35 via intermediate 34. Oxidation of 35 with silver oxide in the presence of sodium hydroxide results in the formation of endiandric acid E (5) in 90 % yield, whereas elaboration of the exo side chain by standard olefination (85 % yield) and alkaline hydrolysis (90 % yield) furnishes endiandric acid F (6). The construction of the remaining compound, endiandric acid G (7), commences with the methyl ester of endiandric acid D (36) and proceeds by partial reduction to the corresponding aldehyde, followed by olefination and hydrolysis with aqueous base as shown in Scheme 6. [Pg.275]

Different optical enantiomers of amino acids also have different properties. L-asparagine, for example, tastes bitter while D-asparagine tastes sweet (see Figure 8.3). L-Phenylalanine is a constituent of the artificial sweetener aspartame (Figure 8.3). When one uses D-phenylalanine the same compound tastes bitter. These examples clearly demonstrate the importance of the use of homochiral compounds. [Pg.239]

Nitric acid also undergoes reactions with organic compounds wherein the acid serves neither as an oxidizing agent nor as a source of hydrogen ions. The formation of organic nitrates by esterification (O-nitration) involves reaction with the hydroxyl group ... [Pg.279]

Monoamidotriphosphate compounds have been evaluated for their combined detergent-sequestrant action [65,66]. Good surfactant properties are also attributed to organoaminodialkylenephosphonic acids. Typical compounds of this kind are the tetra- and trialkali salts of decyl-, dodecyl-, and tetradecylaminodi (methylphosphonate). Values of surface tension and detergency are given in Refs. 118 and 216-219. Wash test results, foam behavior, wetting performance, and surface tensions of aqueous solutions of phosphate esters have been tabulated [12,17,18,33,37,50,52,56,90,220]. [Pg.599]


See other pages where Acidity, also compounds is mentioned: [Pg.259]    [Pg.313]    [Pg.107]    [Pg.99]    [Pg.241]    [Pg.39]    [Pg.219]    [Pg.137]    [Pg.457]    [Pg.505]    [Pg.375]    [Pg.458]    [Pg.502]    [Pg.337]    [Pg.99]    [Pg.334]    [Pg.150]    [Pg.474]    [Pg.300]    [Pg.179]    [Pg.230]    [Pg.102]    [Pg.41]    [Pg.153]    [Pg.566]    [Pg.310]   
See also in sourсe #XX -- [ Pg.622 , Pg.633 ]




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Acidity, also

Acids, also

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