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Dicarboxylic acids condensation

The bis(acid chloride) of 2,2 -dithienylmethane-5,5 -dicarboxylic acid condenses with 5-substituted 2-alkylaminothiophenols to give cyanine dyes of general structure 85.112... [Pg.115]

There are five primary methods to polymerize nylon. They are reaction of a diamine with a dicarboxylic acid, condensation of the appropriate amino acid, ring opening of a lactam, reaction of a diamine with a diacid chloride, and reaction of a diisocyanate with a dicarboxyhc acid. ... [Pg.28]

Nylon A class of synthetic fibres and plastics, polyamides. Manufactured by condensation polymerization of ct, oj-aminomonocarboxylic acids or of aliphatic diamines with aliphatic dicarboxylic acids. Also rormed specifically, e.g. from caprolactam. The different Nylons are identified by reference to the carbon numbers of the diacid and diamine (e.g. Nylon 66 is from hexamethylene diamine and adipic acid). Thermoplastic materials with high m.p., insolubility, toughness, impact resistance, low friction. Used in monofilaments, textiles, cables, insulation and in packing materials. U.S. production 1983 11 megatonnes. [Pg.284]

When cinnamaldehyde, succinic acid and acetic anhydride are heated in the presence of litharge (PbO), the aldehyde and the succinic acid condense to give the dicarboxylic acid (I), which undergoes decarboxylation to give the pale yellow crystalline 1,8-diphenyloctatetrene (II), Kuhn has shown that as the... [Pg.238]

This reaction consists of the condensation of two molecular equivalents of a 1,3 diketone (or a J3-keto-ester) with one equivalent of an aldehyde and one of ammonia. Thus the interaction of ethyl acetoacetate and acetaldehyde and ammonia affords the 1,4-dihy dro-pyridine derivative (1), which when boiled with dilute nitric acid readily undergoes dehydrogenation and aromatisation" to gb e the diethyl ester of collidine (or 2,4,6-trimethyl-pyridine-3,5 dicarboxylic acid (II)). For the initial condensation the solid aldehyde-ammonia can conveniently be used in place of the separate reagents. [Pg.295]

Trimethylene dibromide (1 mol) condenses with ethyl malonate (1 mol) in the presence of sodium ethoxide (2 mols) to form ethyl cydobutane-1 1-dksrboxylate (I). Upon hydrolysis of the latter with alcoholic potassium hydroxide, followed by acidification cyciobutane-1 1-dicarboxylic acid (II) is obtained. [Pg.857]

Polyesters are a second class of condensation polymers and the principles behind their synthesis parallel those of polyamides Ester formation between the functional groups of a dicarboxylic acid and a diol... [Pg.869]

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]

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... [Pg.873]

In addition several other materials have been reported by industrial companies, but have not at the time of writing been commercialised. These include the product of condensation of 2,2-bis-(p-aminocyclohexyl)propane (VI) (Figure 18.28) with a mixture of adipic and azelaic acid (Phillips Petroleum), a research material produced in the old German Democratic Republic obtained by melt condensation of /ranj -cyclohexane-l,4-dicarboxylic acid (VII) (Figure 18.28) and the two trimethylhexamethylenediamine isomers used in the manufacture of Trogamid T, and another amorphous material (Rilsan N by Ato Chimie). [Pg.512]

In 1978 Hiils (Mumcu et al ) described the properties of a block copolymer prepared by condensation of polytetramethylene ether glycol with laurin lactam and decane-1,10-dicarboxylic acid. The materials were introduced as XR3808 and X4006. The polyamide XR3808 is reported to have a specific gravity of 1.02, a yield stress of 24 MPa, a modulus of elasticity of 300 MPa and an elongation of break of 360%. The Swiss company Emser Werke also introduced similar... [Pg.526]

Condensation of polyhydroxy compounds with polybasic acids, e.g. a glycol with a dicarboxylic acid ... [Pg.694]

Esters of dicarboxylic acids undergo an intranolecular version of the Claisen condensation when a five- or six-membered ring can be fonned. [Pg.890]

The Hinsberg synthesis of thiophene derivatives describes the original condensation of diethyl thiodiglycolate and a-diketones under basic conditions which provides 3,4-disubstituted-thiophene-2,5-dicarboxylic acids upon hydrolysis of the crude ester product with aqueous acid. ... [Pg.199]

In 1910, Hinsberg described the reaction between benzil and diethylthiodiacetate, resulting in the preparation of the thiophene ring system. The reaction was run under Claisen condensation conditions, and after hydrolysis with aqueous acid at reflux, the free dicarboxylic acid 1 was produced. [Pg.199]

Tryptophan condenses with a-oxo acids at room temperature to yield l,2,3,4-tetrahydro-j8-carboline-l,3-dicarboxylic acids. Both gly-oxylic acid and pyruvic acid yield the expected products. [Pg.91]

If a Knoevenagel condensation with malonic acid is conducted in refluxing pyridine, a subsequent decarboxylation often occurs. It has been shown that the decarboxylation of a ,/3-unsaturated diesters 3 under these conditions is slow the decarboxylation of the corresponding free dicarboxylic acid is formulated as follows ... [Pg.177]

The first synthesis of a 3//-3-benzazepine, e.g. 65 (R1 = R2 = Me), was achieved by the condensation of phthalaldehyde with a bis[(alkoxycarbonyl)methyl]methylamine.24"25 With sodium methoxide as the base, A%V-bis[(methoxycarbonyl)methyl]pheiiylaniine condenses with the dialdehyde in a similar manner to give dimethyl 3-phenyl-3//-3-benzazepine-2,4-dicar-boxy late (65, Rl — Ph R2 — Me).99 However, replacement of methoxide by potassium tert-butoxide results in formation of 3-phenyl-3//-3-benzazepine-2,4-dicarboxylic acid (65, R1 = Ph R2 = H).25... [Pg.221]

Table 2. 1,4-Diazocine Derivatives by the Condensation of 1,2-Dicarboxylic Acid Derivatives with Arene-1.2-diamines... Table 2. 1,4-Diazocine Derivatives by the Condensation of 1,2-Dicarboxylic Acid Derivatives with Arene-1.2-diamines...
The formation of porphyrins from 1,19-dideoxybi)enes-/r can be achieved starting either from the 1-methyl derivatives or from l,19-dideoxybilene-Z>-l,19-dicarboxylic acid esters. In the first case the desired methine bridge of the porphyrin stems from the 1-methyl group whereas in the latter case orthoformates have to be added in the condensation step as a precursor for the methine unit. The 1-methyl- and also 1,19-dimethyl-l,19-dideoxybilene- > salts can be cy-clized to the corresponding porphyrins with copper(II) acetate in methanol.56 However, when the bilenes contain /i-acceptor substituents, the yields of porphyrins obtained by this method are very low.57... [Pg.591]

Polyester polyols (Scheme 4.4) are prepared by condensation polymerization of dicarboxylic acids and diols. An excess of diol ensures OH functional product, minimizing die possibility of residual acid groups which react with isocyanates to generate C02 and act as inhibitors in catalyzed urethane reactions. The reactants are heated at 200-230°C under vacuum to remove the water by-product and drive the reaction to completion. The most common coreactants include adipic... [Pg.223]

Explain the process of condensation polymerization. How might the polymer obtained from benzene-1,2-dicarboxylic acid and ethylene glycol differ from Dacron ... [Pg.901]

Cortisone acetate has been incorporated into several polyanhydrides (15). The rates of release of cortisone acetate from microcapsules of poly(terephthaUc acid), poly(terephthaUc acid-sebacic acid) 50 50, and poly(carboxyphenoxypropane-sebacic acid) 50 50 are shown in Fig. 8. These microcapsules were produced by an interfacial condensation of a diacyl chloride in methylene chloride with the appropriate dicarboxylic acid in water, with or without the crosslinking agent trimesoyl chloride. This process produces irregular microcapsules with a rough surface. The release rates of cortisone acetate from these microcapsules varied correspondingly with the rate of degradation of the respective polyanhydrides. It can be expected that the duration of release of cortisone acetate from solid microspheres, such as those produced by the hot-melt process, would be considerably longer. [Pg.54]

Three other portions of the molecule which do not fit the polyketide combination pattern (Scheme 7B a,f,n) can be also explained by assuming they are derived from a dicarboxylic acid such as 3-hydroxy-3-methylglutaric acid (Scheme 8b). If that is the case, brevetoxins are a new type of mbced polyketides which are formed by condensation on both ends of dicarboxylic acids (Scheme 8c). In order to prove further the hypothesis, feeding experiments with such putative precursors as succinate, acetoacetate, and propionate are in progress. [Pg.28]

Esters of dicarboxylic acids having hydrogen on the 8 or e carbon atcans undergo intramolecular cyclisation when heated with sodium or with sodium ethoxide. This cyclisation is known as the Dieckmaim reaction. It is essentially an application of the Claiseu (or acetoacetic ester) condensation to the formation of a ring system the condensation occurs internally to produce s... [Pg.856]

Branched polyesters contain oxalkylated primary fatty amines or oxalkyl-ated polyamines together with at least trivalent oxalkylated alkanol that is responsible for branching. The condensation is achieved with a dicarboxylic acid or a dicarboxylic acid anhydride [216]. In this way, branched polyoxyalkylene mixed polyesters are formed. Suitable solvents are water or organic solvents, such as methanol, isopropanol, butanol, or aromatic hydrocarbons (e.g., toluene, xylene). [Pg.334]

Cationic condensation products, namely, the reaction products of a dicarboxylic acid or an ester or acid halide thereof and an aminoalkylamine, that are quatemized are recommended for breaking cmde oil emulsions from fireflooding [365],... [Pg.341]

In general, polyalkylene polyamides-amines are obtained by the condensation of polyalkylenepolyamines with dicarboxylic acids. The materials are alkoxylated with an excess of ethylene oxide or propylene oxide or 1,2-butylene oxide [149],... [Pg.341]

Ordinary dicarboxylic acids or dimeric fatty acids are condensed with fatty amines to give emulsion breakers [822,823,1029,1030]. Oxalkylated fatty amines and fatty amine derivatives have properties other than emulsion braking in particular, they can act as corrosion inhibitors and pour-point depressants. [Pg.342]

Another approach to improve the color formation properties of Malachite Green lactone has been the introduction of nitrogen atoms into the phthalide ring. Thus, condensation of pyridine-2,3-dicarboxylic acid anhydride with dimethylaniline in the presence of zinc chloride has been shown54 to yield a mixture of the 4- and 7-azaphthalides 11 and 12. [Pg.106]


See other pages where Dicarboxylic acids condensation is mentioned: [Pg.214]    [Pg.824]    [Pg.263]    [Pg.332]    [Pg.214]    [Pg.824]    [Pg.263]    [Pg.332]    [Pg.320]    [Pg.304]    [Pg.696]    [Pg.307]    [Pg.489]    [Pg.530]    [Pg.544]    [Pg.199]    [Pg.205]    [Pg.277]    [Pg.293]    [Pg.39]    [Pg.7]   
See also in sourсe #XX -- [ Pg.264 ]




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