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Carboxylic acids From carboxylation reactions

Lukens, R.J. and Sisler, H.D. 2-Thiazolidinethione-4-carboxylic acid from the reaction of captan with cysteine. Science (Washington, DC), 127(3299) 650, 1958. [Pg.1689]

Haines et al. investigated the stereoselective formation of bisfethyienediamine)-cobaltflll) complexes containing optically active tartaric acid from a reaction of [Co(C03)(en)2]Cl and S(—)-tartaric acid in water at steam-bath temperature, two optically active complexes, A-[Co(S-C4H40g)(en)2] Cl and A-[Co(S-C4H306)(en ], were isolated by TLC with silica gel. In the former complex, the tartrate ion acts as a bidentate chelate agent with one free carboxylic acid (IV), and in the latter the tartrate is trinegative. [Pg.84]

Lukens, R. J. and H.D. Sisler. 2-Thiazolidinetliione-4-carboxylic Acid from the Reaction of Captan with Cysteine, Science (Washington, DC), 127(3299) 650 (1958). Lund-Hoie, K. and H.O. Friestad. Photodegradation of the Herbicide Glyphosate in Water, Bull. Environ. Contam. Toxicol, 36 723-729 (1986). [Pg.278]

Separation of a solid carboxylic acid from a reaction mixture. [Pg.719]

Carboxylic and a-dicarboxylic acids from hydrocarbons—Reactions with sodium dispersions s. 11, 725... [Pg.212]

The reaction of trivalent carbocations with carbon monoxide giving acyl cations is the key step in the well-known and industrially used Koch-Haaf reaction of preparing branched carboxylic acids from al-kenes or alcohols. For example, in this way, isobutylene or tert-hutyi alcohol is converted into pivalic acid. In contrast, based on the superacidic activation of electrophiles leading the superelectrophiles (see Chapter 12), we found it possible to formylate isoalkanes to aldehydes, which subsequently rearrange to their corresponding branched ketones. [Pg.165]

The haloform reaction is sometimes used for the preparation of carboxylic acids from methyl ketones... [Pg.766]

Although these humble origins make interesting historical notes m most cases the large scale preparation of carboxylic acids relies on chemical synthesis Virtually none of the 3 X 10 lb of acetic acid produced m the United States each year is obtained from vinegar Instead most industrial acetic acid comes from the reaction of methanol with carbon monoxide... [Pg.806]

Animal fats and vegetable oils are triacylglycerols, or triesters, formed from the reaction of glycerol (1,2, 3-propanetriol) with three long-chain fatty acids. One of the methods used to characterize a fat or an oil is a determination of its saponification number. When treated with boiling aqueous KOH, an ester is saponified into the parent alcohol and fatty acids (as carboxylate ions). The saponification number is the number of milligrams of KOH required to saponify 1.000 g of the fat or oil. In a typical analysis, a 2.085-g sample of butter is added to 25.00 ml of 0.5131 M KOH. After saponification is complete, the excess KOH is back titrated with 10.26 ml of0.5000 M HCl. What is the saponification number for this sample of butter ... [Pg.363]

Garboxylation Reaction. The carboxylation reaction represents the conversion of acetylene and olefins into carboxyHc acids (qv) or their derivatives. The industrially important Reppe process is used in the synthesis of P-unsaturated esters from acetylene. Nickel carbonyl is the catalyst of choice (134). [Pg.69]

The dimer acids [61788-89-4] 9- and 10-carboxystearic acids, and C-21 dicarboxylic acids are products resulting from three different reactions of C-18 unsaturated fatty acids. These reactions are, respectively, self-condensation, reaction with carbon monoxide followed by oxidation of the resulting 9- or 10-formylstearic acid (or, alternatively, by hydrocarboxylation of the unsaturated fatty acid), and Diels-Alder reaction with acryUc acid. The starting materials for these reactions have been almost exclusively tall oil fatty acids or, to a lesser degree, oleic acid, although other unsaturated fatty acid feedstocks can be used (see Carboxylic acids. Fatty acids from tall oil Tall oil). [Pg.113]

In some instances a carbon-carbon bond can be formed with C-nucleophiles. For example, 3-carboxamido-6-methylpyridazine is produced from 3-iodo-6-methylpyridazine by treatment with potassium cyanide in aqueous ethanol and l,3-dimethyl-6-oxo-l,6-dihydro-pyridazine-4-carboxylic acid from 4-chloro-l,3-dimethylpyridazin-6-(lH)-one by reaction with a mixture of cuprous chloride and potassium cyanide. Chloro-substituted pyridazines react with Grignard reagents. For example, 3,4,6-trichloropyridazine reacts with f-butyl-magnesium chloride to give 4-t-butyl-3,5,6-trichloro-l,4-dihydropyridazine (120) and 4,5-di-t-butyl-3,6-dichloro-l,4-dihydropyridazine (121) and both are converted into 4-t-butyl-3,6-dichloropyridazine (122 Scheme 38). [Pg.28]

Thiophene-2-carboxylic acid, 5-(alkylthio)-thiophenes from, 4, 892 Thiophene-2-carboxylic acid, 5-amino-reactions, 4, 810... [Pg.893]

According to Quinkert, photoexcited cyclic ketones may be transformed to open-chain unsaturated carboxylic acids in the presence of molecular oxygen. This reaction may compete efficiently with a-cleavage and secondary transformations thereof. Thus, both stereo iso meric 17-ketones (109) and (110) yield as much as 20% of the unsaturated acid (111) when irradiated in benzene under a stream of oxygen. This photolytic autoxidation has been used notably for partial syntheses of naturally occurring unsaturated 3,4-seco-acids from 3-oxo triterpenes (for references, see ref. 72). [Pg.316]

The first indolization of an arylhydrazone was reported in 1983 by Fischer and Jourdan" by treatment of pyruvic acid 1-methylphenylhydrazone 3 with alcoholic hydrogen chloride. However, it was not until the following year that Fischer and Hess identified the product from this reaction as 1-methyl indole-2-carboxylic acid 4. [Pg.116]

The mixture was stirred at ice bath temperature for 2 hours, 1 ml of methanol was added and the mixture was filtered to remove insoluble impurities. Two milliliters of water were added to the filtrate and the pH was adjusted momentarily to pH 1.5, to effect removal of theenamine block, and then to pH 4.5 with triethylamine. After stirring for an additional hour at ice bath temperature the reaction product,7-(D-0 -phenylglycylamido)-3-chloro-3-cephem-4-carboxylic acid (zwitterion) precipitated from the reaction mixture as a crystalline solid. [Pg.259]

The 3-o-ch orophenvl-5-methvlisoxa2ole4-carboxylic acid, from which the acid chloride was prepared, was obtained by hydrolysis of the ester product of the reaction between o-chloro-benzohydroxamic chlorideand ethyl acetoacetate in methanolic sodium methoxide. Reaction with thionyl chloride gave the starting material. [Pg.386]

Preparation of 2-Cyclopropylcarbony/amido-5-Chlorobenzophenone To 400.5 g (1.73 mols) of 2-amino-5-chlorobenzophenone dissolved in 220 g (2.18 mols) of triethylamine and 3.5 liters of tetrahydrofuran is added cautiously 181 g (1.73 mols) of cyclopropane-carboxylic acid chloride. The reaction is refluxed 2 /2 hours and allowed to cool to room temperature. The solvent is then removed under vacuum to obtain 2-cyclopropylcarbonyl-amido-5-chlorobenzophenone as a residue which is dissolved in 1 liter of methylene chloride, washed twice with 5% hydrochloric acid, and then twice with 10% potassium hydroxide. The methylene chloride solution is then dried over anhydrous magnesium sulfate, filtered and the solvent removed under vacuum. The residue is recrystallized from 1,500 ml of methanol, charcoal-treating the hot solution to give 356 g of 2-cyclopropylcarbonylamido-5-chlorobenzophenone, MP 105° to 105.5°C (69% yield). [Pg.1278]

The above methods occurred in 3 steps, therefore, these methods are not preferred. For instance, in the first step, o-, m-, and p-bromostyrene and its copolymer are synthesized. In the second step, Li-PS is synthesized from the reaction of copolymers with an organic compound containing LI. The abovementioned reactions are made with different compounds of Li-PS in the third step. These methods were also investigated by Ayres and Mann [34], who used the synthesis of PS containing chloro groups with chloromethylated PS as the first step. In the second step, formil resin was obtained by oxidation of chlorometylated PS. In the third step, carboxyl-ated PS was obtained by the oxidation of formol resin with acetic acid at 20°C for 48 h. There are some disad-... [Pg.263]

Alkynes, like alkenes, can be cleaved by reaction with powerful oxidizing agents such as ozone or KMnC, although the reaction is of little value and we mention it only for completeness. A triple bond is generally less reactive than a double bond and yields of cleavage products are sometimes low. The products obtained from cleavage of an internal alkyne are carboxylic acids from a terminal alkyne, CO2 is formed as one product. [Pg.270]

Carboxylic acids can be prepared from nitriles by reaction with hot aqueous acid or base by a mechanism that we ll see in Section 20.9. Since nitriles themselves are usually made by Sts 2 reaction of a primary or secondary7 alkyl halide with CN , the two-step sequence of cyanide displacement followed by nitiile hydrolysis is a good way to make a carboxylic acid from an alkyl halide (RBr —> RC=N RC02H). [Pg.762]


See other pages where Carboxylic acids From carboxylation reactions is mentioned: [Pg.74]    [Pg.1642]    [Pg.274]    [Pg.356]    [Pg.115]    [Pg.81]    [Pg.875]    [Pg.29]    [Pg.512]    [Pg.294]    [Pg.479]    [Pg.306]    [Pg.381]    [Pg.62]    [Pg.310]    [Pg.178]    [Pg.88]    [Pg.611]    [Pg.199]    [Pg.139]    [Pg.223]    [Pg.773]    [Pg.1281]    [Pg.1283]    [Pg.1284]    [Pg.1294]    [Pg.78]   


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Acid chloride, alcohols from reaction with carboxylate ions

Carboxylic Acids, isolation from salts reactions

Carboxylic acids From oxidative cleavage reactions

Carboxylic acids from amine-catalyzed condensation reactions

Carboxylic acids reactions

Friedel-Crafts acylation reactions synthesis from carboxylic acids

From acyl halides reaction with carboxylic acids

From carboxylic acids

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