Carboxylic dicarboxylic

Many workers have shown [3,19] that the gallery height in LDHs containing long chain aliphatic carboxylate, dicarboxylate, sulfonate or sulfate guests increases as the chain length increases. For the case of o, 6t)-dicarboxylate anions OOC(CH2)nCOO , the basal spacing shows a mean increase of 0.127 nm/CH2 from n = 3 to 12 as shown in Fig. 21 [213] for Mg/Al LDH... 

Oxidative fission of a carbon-carbon bond of aliphatic hydrocarbons is generally devoid of preparative interest because the chain may be broken at various places and mixtures of carboxylic, dicarboxylic, and hydroxy carboxylic acids with other oxidation products are formed. If, however, certain experimental conditions are precisely maintained, alkanes of high molecular weight can be oxidized catalytically by air, e.g., by the Fischer-Tropsch-Gatsch process, reasonably homogeneously to fatty acids of medium chain length (C10-C18), and this has assumed much industrial importance for the manufacture of soap. 

Electrolysis, under similar conditions, of a mixture of two carboxylic acids RCOOH and R COOH leads, in addition to normal coupling products R—R and R —R, to cross coupling R—R. If a mixture of a saturated carboxylic acid and a half ester of an ato-dicarboxylic acid is electrolysed, there are three main products, viz., a hydrocarbon (I), a mono-ester (II), and a di-ester (HI) and these are readily separable by distillation. Some unsaturated ester (IV) is often present in small quantity. 

Thiazole carboxylic acid (70), R, - Rj = H, can be also obtained from decarboxylation of 2,5-thiazole dicarboxylic acids. 

Hydrolysis of ethyl 4-methyl-2,5-thiazole dicarboxylate (9) or dicar-boxylic acid dichloride gives an excellent yield of 4-methyl-5 thiazole carboxylic acid (10) instead of the dicarboxylic acid (Scheme 6). This lability is a general Property of 2-thiazolecarboxylic acids. 

Compounds with two carboxyl groups as illustrated by entries 10 through 12 are distinguished by the suffix dioic acid or dicarboxylic acid as appropnafe The final e m fhe base name of fhe alkane is refamed... 

TABLE E Selected Physical Properties of Representative Carboxylic Acids and Dicarboxylic Acids... 

If a polyamide is prepared in the presence of a large excess of dicarboxylic acid, the average chain will have a carboxyl group at each end ... 

Ethylene—Dicarboxylic Acid Copolymers. Partial neutralization of copolymers containing carboxyls in pairs on adjacent carbons, eg, ethylene—maleic acid, has been described (11). Surprisingly, there is no increase in stiffness related to neutralization. Salts with divalent metal cations are not melt processible. The close spacing of the paired carboxyl groups has resulted in ionic cluster morphology which is distinct from that of the commercial ionomer family. 

Aluminum salts of carboxylic acids, aluminum carboxylates, may occur as aluminum tricarboxylates (normal aluminum carboxylates), Al(OOCR)2 monohydroxy (monobasic) aluminum dicarboxylates, (RCOO)2Al(OH) and dihydroxy (dibasic) aluminum monocarboxylates, RCOOAl(OH)2. Aluminum carboxylates are used in three general areas textiles, gelling, and pharmaceuticals. Derivatives of low molecular weight carboxyUc acids have been mainly associated with textile appHcations those of fatty carboxyUc acids are associated with gelling salts and more complex carboxylates find appHcations in pharmaceuticals. 

This group of aluminum carboxylates is characterized mainly by its abiUty to gel vegetable oils and hydrocarbons. Again, monocarboxylate, dicarboxylate, and tricarboxylate salts are important. The chemical, physical, and biological properties of the various types of aluminum stearates have been reviewed (29). Other products include aluminum palmitate and aluminum 2-ethylhexanoate (30). 

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). 

Pyridazine carboxylates and dicarboxylates undergo cycloaddition reactions with unsaturated compounds with inverse electron demand to afford substituted pyridines and benzenes respectively (Scheme 45). 

Practically all pyridazine-carboxylic and -polycarboxylic acids undergo decarboxylation when heated above 200 °C. As the corresponding products are usually isolated in high yields, decarboxylation is frequently used as the best synthetic route for many pyridazine and pyridazinone derivatives. For example, pyridazine-3-carboxylic acid eliminates carbon dioxide when heated at reduced pressure to give pyridazine in almost quantitative yield, but pyridazine is obtained in poor yield from pyridazine-4-carboxylic acid. Decarboxylation is usually carried out in acid solution, or by heating dry silver salts, while organic bases such as aniline, dimethylaniline and quinoline are used as catalysts for monodecarboxylation of pyridazine-4,5-dicarboxylic acids. 

A similar intramolecular trapping of the intermediate (511) from the photolysis of the corresponding methyl tetrazole-l,5-dicarboxylate (510) gave methyl 5-methoxy-l,2,4-oxadiazole-3-carboxylate (512). 

The treatment of 3-benzoyl-2-phenylisoxazolidine with strong base generated an aldehyde and a ketimine <74X1121). Under these conditions dimethyl 2-a-methoxyisoxazolidine-3,3-dicarboxylic acid (186) produced isoxazoline-2-carboxylic acid. Reaction of the monomethyl amide (187) gave the corresponding isoxazoline-2-carboxamide (Scheme 60). CD was used in the conformational studies <79X213). 

In an attempt to prepare an isothiazolobenzodiazepine, ethyl 5-o-aminoanilino-3-methyl-isothiazole-4-carboxylate was treated with sodium methoxide, but the only reaction was transesterification to the methyl ester 76UC(B)394). Only the 5-ester group of dimethyl 3-methylisothiazole-4,5-dicarboxylate reacts with iV,iV -diphenylguanidine, as with the corresponding isoxazole compound, but the product could not be cyclized, even under drastic conditions. This is in marked constrast to the isoxazole compound which cyclized at room temperature (80JCS(P1)1667). 

H-Azepine, 2,6,7-tri(methoxycarbonyl)-ring inversion, 7, 499 Azepine-1-carboxylic acid tricarbonylruthenium complexes, 7, 523 1 H-Azepine-2,3-dicarboxylic acid, 4,7-dihydro-6-phenyl-diethyl ester synthesis, 7, 539-540 1 H-Azepine-3,6-dicarboxylic acid... 

Chroman-6-carboxylic acid, 8-hydroxy-2-methyl-4-0X0—see Rosellinic acid, 718 Chroman-2,7-dicarboxylic acid, 2,4,4-trimethyl-formation, 3, 733... 

Lumazine-6-carboxylic acid, 7-hydroxy-tautomerism, 3, 271 Lumazine-7-carboxylic acid synthesis, 3, 304 Lumazine-6,7-dicarboxylic acid decarboxylation, 3, 304 reactions, 3, 304 synthesis, 3, 320 Lumazine-6,7-dione catabolism, 3, 322... 

Pteridine-7-carboxylic acid, 6-oxo-synthesis, 3, 310 Pteridinecarboxylic acids structure, 3, 276-277 Pteridine-4-carboxylic acids ethyl ester hydrolysis, 3, 276 Pteridine-6-carboxylic acids properties, 3, 277 reactions, 3, 304 Pteridine-7-carboxylic acids properties, 3, 277 reactions, 3, 304 Pteridine-6,7-dicarboxylic acid properties, 3, 277 Pteridine-2,4-dione, 7-hydroxy-tautomerism, 3, 271... 

Claisen ester condensation, 6, 279 Thiazolecarboxylic acid chlorides reactions, 6, 279-280 Thiazolecarboxylic acid hydrazides synthesis, 6, 280 Thiazolecarboxylic acids acidity, 6, 279 decarboxylation, 6, 279 reactions, S, 92 6, 274 Thiazole-2-carboxylic acids decarboxylation, S, 92 Thiazole-4-carboxylic acids stability, S, 92 Thiazole-5-carboxylic acids decarboxylation, S, 92 Thiazole-4,5-dicarboxylic acid, 2-amino-diethyl ester reduction, 6, 279 Thiazole-4,5-dicarboxylic acids diethyl ester saponification, 6, 279 Thiazolediones diazo coupling, 5, 59 Thiazoles, 6, 235-331 ab initio calculations, 6, 236 acidity, S, 49 acylation, 6, 256 alkylation, S, 58, 73 6, 253, 256 analytical uses, 6, 328 antifogging agents... 

Methylnorbornene-2,3-dicarboxylic anhydride (5-methylnorborn-5-ene-2-endo-3-endo-di-carboxylic anhydride) [25134-21-8] M 178.2, m 88.5-89 . Purified by thin layer chromatography on AI2O3 (previously boiled in EtOAc) and eluted with hexane- C6Hg (1 2) then recrystd from CgH -hexane. The free acid has m 118.5-119.5 . [Miranov et al. Tetrahedron 19 1939 1963.]... 

The present method for preparing aromatic dicarboxylic acids has been used to convert phthalic or isophthalic acid to tereph-thalic acid (90-95%) 2,2 -biphenyldicarboxylic acid to 4,4 -biphenyldicarboxylic acid 3,4-pyrroledicarboxylic acid to 2,5-pyr-roledicarboxylic acid and 2,3-pyridinedicarboxylic acid to 2,5-pyridinedicarboxylic acid. A closely related method for preparing aromatic dicarboxylic acids is the thermal disproportionation of the potassium salt of an aromatic monocarboxylic acid to an equimolar mixture of the corresponding aromatic hydrocarbon and the dipotassium salt of an aromatic dicarboxylic acid. The disproportionation method has been used to convert benzoic acid to terephthalic acid (90-95%) pyridine-carboxylic acids to 2,5-pyridinedicarboxylic acid (30-50%) 2-furoic acid to 2,5-furandicarboxylic acid 2-thiophenecar-boxylic acid to 2,5-thiophenedicarboxylic acid and 2-quinoline-carboxylic acid to 2,4-quinolinedicarboxylic acid. One or the other of these two methods is often the best way to make otherwise inaccessible aromatic dicarboxylic acids. The two methods were recently reviewed. ... 

Plasticizers can be classified according to their chemical nature. The most important classes of plasticizers used in rubber adhesives are phthalates, polymeric plasticizers, and esters. The group phthalate plasticizers constitutes the biggest and most widely used plasticizers. The linear alkyl phthalates impart improved low-temperature performance and have reduced volatility. Most of the polymeric plasticizers are saturated polyesters obtained by reaction of a diol with a dicarboxylic acid. The most common diols are propanediol, 1,3- and 1,4-butanediol, and 1,6-hexanediol. Adipic, phthalic and sebacic acids are common carboxylic acids used in the manufacture of polymeric plasticizers. Some poly-hydroxybutyrates are used in rubber adhesive formulations. Both the molecular weight and the chemical nature determine the performance of the polymeric plasticizers. Increasing the molecular weight reduces the volatility of the plasticizer but reduces the plasticizing efficiency and low-temperature properties. Typical esters used as plasticizers are n-butyl acetate and cellulose acetobutyrate. 

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