Long-chain dicarboxylic acids

Long-chain dicarboxylic acids are produced by a number of reactions ... 

This new hydrotrope posed an intriguing problem the explanation of the hydrotropic action of such a long chain dicarboxylic acid. The problem was solved in a series of articles (11-14) which contain the essential experimental information for this article. These articles each provided a part of the total framework of the problem and we considered a unified treatment essential in order to present a systematic pattern for the different aspects Involved. 

As a model experiment to see the effect of orthoesters in reducing the content of terminal carboxyl, aliphatic long-chain dicarboxylic acid and a large excess of various additives reacted in biphenyl at 250°C, and the rate constants of the pseudo-first-order reaction were compared. The reaction rate constant decreases in the order of tetraphenyl... 

Kolbe electrolysis is generally useful for the formation of hydrocarbons from monocarboxylic acids and for the preparation of many difunctional compounds as well. A specific illustration is the synthesis of esters of long-chain dicarboxylic acids from monoesters of appropriate dicarboxylic acids (see p. 33). A number of these syntheses are discussed by Fichter.4 In the present preparation, a two-compartment cell is employed to avoid, or at least greatly reduce, undesired reduction of the nitro group at the cathode. It seems likely that the procedure could be adapted to the preparation of other difunctional compounds containing groups that are easily reduced. 

Brown-Walker reaction — Important generalization and extension of the Kolbe reaction (1891) (- Kolbe synthesis) leading to the synthesis of a variety of long-chain dicarboxylic acids and esters using monoesters of dicar-boxylic precursors. Among the most used application belongs the production of sebacic acid diethylester from hydrogen ethyladipate... 

An acute catabolic state with hypoglycemia, hjrper-ammonemia, raised activities of serum aspartate transaminase and creatine phosphokinase, and increased urinary nitrogen and serum long chain dicarboxylic acid. 

Ruzicka cyclisation The reaction of a long chained dicarboxylic acid with Th02 to form a cyclic... 

If free co-unsaturated fatty acids were oxidized, the resulting long chain dicarboxylic acids precipitated as white solids after the reaction mixture had been cooled to 0°C and were isolated by filtration. Their purity, considering the oxidative cleavage of 9decenoic and 10-undecenoic acid, was about 95% ... 

Many of these disorders are associated with the urinary excretion of acylcarnitines, acyl conjugates of glycine, and dicarboxylic acids that are characteristic of the metabolic block. A general conclusion derived from studies of these disorders is that an impairment of p-oxidation makes fatty acids available for microsomal (o-oxidation by which fatty acids are oxidized at their terminal (to) methyl group or at their penultimate (o) - 1) carbon atom. Molecular oxygen is required for this oxidation and the hydroxylated fatty acids are further oxidized to dicarboxylic acids. Long-chain dicarboxylic acids can be... 

On the other hand, also two CO2 molecules may react with a different number of ethene molecules yielding for instance maleic acid, succinic acid, adipic acid or long-chain dicarboxylic acids. Also these products are either bulk or fine chemicals of high commercial value. 

K. Kato and N. Uemura, Process for the preparation of long-chain dicarboxylic acids by fermentation, US Patent 4 339 536, assigned to Nippon Mining Co., Ltd. (Tokyo, JP), July 13,1982. 

A. Kamal, S. Gurrala, and W.N. Fadnavis, Process for preparing long-chain dicarboxylic acids, US Patent 8 383 373, assigned to Council of Scientific Industrial Research (New Delhi, IN), February 26,2013. 

Picataggio S, Rohrer T, Deanda K, Lanning D, Reynolds R, Mielenz J, Eirich LD. (1992). Metabolic engineering of Candida tropicalis for the production of long-chain dicarboxylic acids. Biotechnology (N Y), 10, 894-898. 

The intensity of microbial growth on plastic material depends on the type of synthetic polymer, but also on the type of additives, especially plasticizers used to improve the processing characteristics of the polymer. There are plasticizers such as fatty acid esters and long-chain dicarboxylic acid esters which are most susceptible to fungal growth while phthalate and phosphate esters with alkylol substituents are generally resistant. However, as plastic materials in operation are always subject to contamination with traces of nutrients for micro-organisms. 

In recent years, Novamont developed a family of aliphatic-aromatic copolyesters with its aliphatic dicarboxylic acid component predominantly based on long chain dicarboxylic acids of natural origin (sebacic acid, azelaic acid and brassylic acid) [56-58]. Compared with aliphatic-aromatic polyesters where the aliphatic dicarboxylic component is a shorter carbon chain length, such as BTA polyesters, these copolyesters do not show the sudden decrease of biodegradation properties above... 

Origo-Bi is based on a range of aliphatic and aliphatic-aromatic copolyesters mainly composed of terephthalic acid, long chain dicarboxylic acids of renewable source and 1,4-butanediol. Depending on the dicarboxylic acid used, the ratio of terephthalic acid can be tuned, in order to fulfil biodegradability and specific performance criteria. 

Deuterated fatty acids can be separated from non-deuterated in part at least on WCOT columns coated with polar stationary phases [693,695], t-Butyldimethylsilyl ester derivatives (see Chapters 4 and 7) are useful for GC-mass spectrometric estimation of these compounds [692,709,1004], Long-chain dicarboxylic acids have been separated by GC and identified by GC-MS in the semm of patients suffering from Reye s syndrome [663] and in the lipids of royal Jelly [542,543], Brominated vegetable oils are added to soft drinks to disperse flavouring agents after acid-catalysed methanolysis, the methyl ester derivatives of fatty acids containing two, four and six bromine atoms have been separated on packed [538] or fused silica [151] columns with non-polar silicone stationary phases. 

Liu, S. Li, C. Xie, L. Cao, Z. Intracellular pH and metabolic activity of long-chain dicarboxylic acid-producing yeast Candida tropicalis. J. Biosci. Bioeng. 2003,96, 349-353. 

A long-chain dicarboxylic acid may also form a cyclic acid anhydride, in which the -CO.O.CO- group forms part of a ring. Acid anhydrides can be prepared by reaction of an acyl halide with the sodium salt of a carboxylic acid, e.g. ... 

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