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Phosphoric acid synthesis

Phosphitylation with Azolides of Phosphorous Acid Synthesis of Oligonucleotides... [Pg.261]

Most of the phosphoms produced as the element is later converted to high purity phosphoric acid and phosphate compounds the remainder is used in direct chemical synthesis to produce high purity products. In contrast, phosphoric acid produced by the wet process is used in lower purity apphcations, especially in fertiliser and to a lesser degree in animal feed (see Feeds AND FEED ADDITIVES). More recendy, a small portion of wet acid is purified in a second process and then also used in high purity acid and phosphate compound apphcations. [Pg.347]

Synthesis. Hydroxyhydroquiaone is not produced on a large scale, but many uses for it are being developed. The most convenient preparation of hydroxyhydroquiaone is the reaction of -benzoquiaone with acetic anhydride ia the preseace of sulfuric acid or phosphoric acid. The resultant triacetate (29) can be hydrolyzed to hydroxyhydroquiaone (86). [Pg.380]

A Methylamino)phenol. This derivative (15) is easily soluble ia ethyl acetate, ethanol, diethyl ether, and benzene. It is also soluble ia hot water, but only spatingly soluble ia cold water. Industrial synthesis is by heating 3-(A/-methylamino)benzenesulfonic acid with sodium hydroxide at 200—220°C (179) or by the reaction of resorciaol with methylamiae ia the presence of aqueous phosphoric acid at 200°C (180). [Pg.315]

Apphcations include ka olin clay dewatering, separation of fish oils from press Hquor, starch and gluten concentration, clarification of wet-process phosphoric acid, tar sands, and concentrations of yeast, bacteria, and fungi from growth media in protein synthesis (14). [Pg.411]

Acid-Gatalyzed Synthesis. The acid-catalysed reaction of alkenes with hydrogen sulfide to prepare thiols can be accompHshed using a strong acid (sulfuric or phosphoric acid) catalyst. Thiols can also be prepared continuously over a variety of soHd acid catalysts, such as seoHtes, sulfonic acid-containing resin catalysts, or aluminas (22). The continuous process is utilised commercially to manufacture the more important thiols (23,24). The acid-catalysed reaction is commonly classed as a Markownikoff addition. Examples of two important industrial processes are 2-methyl-2-propanethiol and 2-propanethiol, given in equations 1 and 2, respectively. [Pg.10]

The Grewe synthesis of /V-methylmorphinan [3882-38-0] (40), which paved the way for the preparation of dextromethorphan and numerous analogues, follows standard reactions to 2-meth5l-l-benzyl-l,2,3,4,5,6,7,8-octahydroisoquinoline. Cyclization of this compound with phosphoric acid gave a mixture of isomers from which /V-methylmorphinan was separated. [Pg.523]

Imidazole-5-thione, 4,4-diphenyl-tautomerism, 5, 368 3 H-Imidazole-2-thione, 1,3-dimethyl-structure, 5, 367 Imidazole-2-thiones acidity, 5, 367 betaines, 5, 372 synthesis, 5, 481 tautomerism, 5, 367 3H-Imidazole-2-thiones synthesis, 5, 473, 6, 992 Imidazolides deacylation, 5, 453 mass spectra, 5, 360 phosphoric acid reactions, 5, 454 reactions, 5, 451-453 Imidazolidine, l-alkyl-3-phenyl-N-oxidation, 5, 427 Imidazolidine, 1,3-benzyl-2-phenyl-oxidation, S, 427... [Pg.657]

On treatment of N-methylpapaverine, formed by the lithium aluminum hydride reduction of papaverine methiodide with phosphoric acid, N-methylpavine is formed which is identical with the racemic alkaloid argemonine. This reaction was used for the synthesis of the alkaloid (-h)-coreximine (268) (174) and similar compounds containing the proto-berberine grouping in the molecule (269,270). [Pg.292]

Tlie condensation of nitromalonic aldehyde (26) with 2,6-diaminopyridine (27) in the presence of phosphoric acid, affording 2-amino-6-nitro-l,8-naphthyridine (28,37%) (77TL2087), is another example of a successful application of a nitro aliphatic compound in the synthesis of nitronaphthy-ridines. [Pg.290]

The Arbuzov reaction,also called the Michaelis-Arbuzov reaction, allows for the synthesis of pentavalent alkyl phosphoric acid esters 4 from trivalent phosphoric acid esters 1 (Z,Z = R,OR) by treatment with alkyl halides 2. [Pg.14]

Phosphine(s), chirality of, 314 Phosphite, DNA synthesis and, 1115 oxidation of, 1116 Phospholipid, 1066-1067 classification of, 1066 Phosphopantetheine, coenzyme A from. 817 structure of, 1127 Phosphoramidite, DNA synthesis and, 1115 Phosphoranc, 720 Phosphoric acid, pKa of, 51 Phosphoric acid anhydride, 1127 Phosphorus, hybridization of, 20 Phosphorus oxychloride, alcohol dehydration with. 620-622 Phosphorus tribromide, reaction with alcohols. 344. 618 Photochemical reaction, 1181 Photolithography, 505-506 resists for, 505-506 Photon, 419 energy- of. 420 Photosynthesis, 973-974 Phthalic acid, structure of, 753 Phthalimide, Gabriel amine synthesis and, 929... [Pg.1311]

The acidic catalysts used for these reactions include formic acid, HX (X = F, Cl, Br), oxalic acid, phosphoric acid, sulfuric acid, sulfamic acid, and p-toluenesulfonic acid.4 Oxalic acid is preferred since resins with low color can be obtained. Oxalic acid also decomposes at high temperatures (>180°C) to C02, CO, and water, which facilitates the removal of this catalyst thermally. Typically, 1-6 wt % catalyst is used. Hydrochloric acid results in corrosive materials and reportedly releases carcinogenic chloromethyl ether by-products during resin synthesis.2... [Pg.379]

In 1950 the Fischer-Tropsch synthesis was banned in Germany by the allied forces. Sinarol, a high paraffinic kerosene fraction sold by Shell, was used as a substitute. This ban coincided with the rapid development of the European petrochemical industry, and in due time Fischer-Tropsch synthesis applied to the production of paraffins became uneconomic anyway. After the war there was a steady worldwide increase in the demand for surfactants. In order to continually meet the demand for synthetic detergents, the industry was compelled to find a substitute for /z-paraffin. This was achieved by the oligomerization of the propene part of raffinate gases with phosphoric acid catalyst at 200°C and about 20 bars pressure to produce tetrapropene. Tetrapropene was inexpensive, comprising a defined C cut and an olefinic double bond. Instead of the Lewis acid, aluminum chloride, hydrofluoric acid could now be used as a considerably milder, more economical, and easier-to-handle alkylation catalyst [4],... [Pg.42]

Orthophosphoric acid containing three acid OH groups in the molecule offers many opportunities for the realization of surface-active molecular structures. But phosphoric acid also possesses the ability to form polyacids in an widespread manner. Pyrophophoric acid and triphosphoric acid are substances that have been known for a long time. This presents further possibilities for interesting synthesis. [Pg.552]

There are some means for synthesis of defined primary or secondary esters. Monoester salts of phosphoric acid, for instance, are prepared by addition of alcohol or ethoxylated alcohol, alkali fluoride, and pyrophosphoryl chloride (C12P0)20 in a molar ratio of 0.9-1.5 0.05-1 1.0 at -50 to +10°C and hydrolysis of the Cl-containing intermediates with base. Thus, 32.3 g (C12P0)20 was treated at -50°C with 23.9 g lauryl alcohol in the presence of 0.7 g KF and the mixture was slowly warmed to room temperature and hydrolyzed with H20 and 40% NaOH to give 83% sodium monolauryl phosphate. The monoester salts showed comparable or better washing and foaming efficiency than a commercial product [12]. [Pg.557]

The catalyst is phosphoric acid. The laboratory synthesis of alcohols is by nucleophilic substitution of haloalkanes. [Pg.875]

There are several schemes for the synthesis of cellulose formates (slow) reaction of the polymer with formic acid faster reaction in the presence of a mineral acid catalyst, e.g., sulfuric or phosphoric acid. The latter route is usually associated with extensive degradation of the polymer chain. Reaction of SOCI2 with DMF produces the Vilsmeier-Haack adduct (HC(Cl) = N (CH3)2C1 ) [145]. In the presence of base, cellulose reacts with this adduct to form the unstable intermediate (Cell - O - CH = N" (CH3)2C1 ) from which cellulose formate is obtained by hydrolysis. The DS ranges from 1.2 to 2.5 and the order of reactivity is 5 > C2 > C3 [140-143,146]. [Pg.125]

The synthesis of ATP from ADP and phosphoric acid is nonspontaneous. Consequently, ATP synthesis must be coupied to some more spontaneous reaction. Example 14-10 describes one of these reactions. [Pg.1028]

C21-0082. Calcium dihydrogen phosphate is a common phosphoras fertilizer that is made by treating fluoroapatite with phosphoric acid. Hydrogen fluoride is a by-product of the synthesis. Write a balanced equation for the production of this fertilizer and calculate the mass percent of phosphorus in the fertilizer. [Pg.1551]

The preparation of phosphate esters has been reviewed and full details have appeared of the use of 2-chloromethyl-4-nitrophenyl esters (reported last year) in the synthesis of monoesters and mixed dialkyl esters of phosphoric acid. [Pg.96]

When AMP is heated under reflux in DMF, the 2, 3 -cyclic phosphate is formed, and cyclic phosphates can also be obtained from nucleosides and ortho-, pyro-, or poly-phosphoric acids under the same conditions. Promotion of phosphorylation by DMF is well known and the reaction with AMP is probably intermolecular as no 3, 5 -cyclic AMP can be detected. Minor products in the latter reaction are the 2, 3 -cyclic 5 -diphosphate and the 2 (30,5 -diphosphate. The synthesis of adenosine 2 (3 )-phosphate 5 -pyrophosphate has been achieved by the phosphoromorpholidate method used in a synthesis of Co A. ... [Pg.123]

Cochineal pigments are extracted from dried bodies of female insects with water or with ethanol the result is a red solution that is concentrated in order to obtain the 2 to 5% carminic acid concentration customary for commercial cochineal. For carmine lakes, the minimum content of carminic acid is 50%. An industrial procedure applied in Spain uses ammonium hydroxide as the extracting agent and phosphoric acid as the acidifying agent. For analytical purposes the extraction is carried out with 2 N HCl at 100°C. The chemical synthesis of carminic acid has also been reported and is the subject of European and United States patents. ... [Pg.335]

Smith, M., Moffatt, J.G., Khorana, H.G. (1958) Carbodumides. VIII. Observations on the Reactions of Carbodiimides with Acids and Some New Applications in the Synthesis of Phosphoric Acid Esters. Journal of the American Chemical Society, 80, 6204-6212. [Pg.185]

Kenner, G.W., Todd, A.R., Weymouth, F.J. (1952) Nucleotides. Part XVII. N-Chloroamides as Reagents for the Chlorination of Diesters of Phosphorous Acid. A New Synthesis of Uridine-5 Pyrophosphate. Journal of the Chemical Society, 3675-3681. [Pg.190]

The condensation reactions are preferentially carried out in pyridine. As reactive species for phosphorylation of the nucleoside R OH (synthesis of a phosphortriester), the phosphoric acid azolide has been assumed. The mixed phosphoric sulfonic anhydride and a pyrophosphate tetraester have been suggested as intermediates leading to the phosphoric acid azolide. [Pg.272]


See other pages where Phosphoric acid synthesis is mentioned: [Pg.307]    [Pg.308]    [Pg.21]    [Pg.81]    [Pg.351]    [Pg.377]    [Pg.419]    [Pg.462]    [Pg.142]    [Pg.2106]    [Pg.164]    [Pg.5]    [Pg.293]    [Pg.555]    [Pg.580]    [Pg.134]    [Pg.245]   


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