Coal-tars quinoline

Eastman Kodak Company white label synthetic quinoline was used. The use of coal tar quinoline introduces non-extract-able aromatic impurities which contaminate the product. 

Replacing one carbon atom of naphthalene with an a2omethene linkage creates the isomeric heterocycles 1- and 2-a2anaphthalene. Better known by their trivial names quinoline [91-22-5] (1) and isoquinoline [119-65-3] (2), these compounds have been the subject of extensive investigation since their extraction from coal tar in the nineteenth century. The variety of studies cover fields as diverse as molecular orbital theory and corrosion prevention. There is also a vast patent Hterature. The best assurance of continuing interest is the frequency with which quinoline and isoquinoline stmctures occur in alkaloids (qv) and pharmaceuticals (qv), for example, quinine [130-95-0] and morphine [57-27-2] (see Alkaloids). 

Mesophase formation in coal-tar pitch is encouraged by a reduction of the natural quinoline-insoluble matter content, which resembles carbon black but is not optically anisotropic and is characterized by an atomic carbon hydrogen ratio of 4 1. In contrast, the atomic carbon hydrogen ratio of mesophase is about 2 1. 

Coal-Tar Pitch Coke. Coal-tar pitch is used to produce needle coke primarily in Japan. Processes for producing needle coke from pitch have also been developed in Germany (4). The key to producing needle coke from coal tar or coal-tar pitch is the removal of the high concentrations of infusible sohds, or material insoluble in quinoline (QI), which are present in the original tar. The QI inhibits the growth of mesophase and results in an isotropic, high CTE coke from coal-tar pitch. After removal of the QI, very anisotropic and low CTE cokes are obtained from coal-tar-based materials. 

Coal-tar pitches generally soften around 110°C, are about 70 wl% soluble in toluene and 12 wt% insoluble m quinoline. Excessive amounts of primary qumohne insolubles (QI) would contribute to increased carbon yield, but such a pitch may not wet coke well and could hinder the penetration of pitch into the coke voids. 

N— compounds used as acid inhibitors include heterocyclic bases, such as pyridine, quinoline and various amines. Carassiti describes the inhibitive action of decylamine and quinoline, as well as phenylthiourea and dibenzyl-sulphoxides for the protection of stainless steels in hydrochloric acid pickling. Hudson e/a/. refer to coal tar base fractions for inhibition in sulphuric and hydrochloric acid solutions. Good results are reported with 0-25 vol. Vo of distilled quinoline bases with addition of 0 05m sodium chloride in 4n sulphuric acid at 93°C. The sodium chloride is acting synergistically, e.g. 0-05m NaCl raises the percentage inhibition given by 0-1% quinoline in 2n H2SO4 from 43 to 79%. Similarly, potassium iodide improves the action of phenylthiourea . 

Still bottom residues produced in the distillation of quinoline from coal tar can be oxidized and are suitable as a metal corrosion inhibitor for use in aqueous acid solutions [244]. 

E. Jacobson in 1882 fused phthalic anhydride with quinoline bases obtained from coal tar, which also contained quinaldine (136). He thus received quinophthalone (137). Quinophthalone derivatives bearing sulfonic or carboxylic acid functions represent suitable anionic dyes. Derivatives carrying basic side chains containing quarternary nitrogen, on the other hand, provide cationic dyes. The compounds are used especially as disperse dyes [1]. 

Philip L. Walker, Jr. Dr. Taylor has been describing results for the carbonization of a coal tar pitch which was very low in quinoline insolubles (QI). In this case the mosaic unit which he finds in the cokes is quite large. I am wondering if he has looked at pitches of a higher QI content and if the mosaic size in the cokes decreases with increasing QI content in the original pitch ... 

Coal-tar distillates -quinoline from [QUINOLINES AND ISOQUINOLINES] (Vol 20)... 

Manufacture From Coal Tar. Commercially, quinoline is isolated from coaltar distillates. Tar acids are removed by caustic extraction, and the oil is distilled to produce the methylnaphthalene fraction (230-280°C). 

Quinoline is isolated from coal-tar distillates in a process in which the tar acids are removed by caustic extraction, and the oil is distilled to produce the methylnaphthalene fraction (230 to 280°C). Washing with dilute sulfuric acid produces sulfate salts, from which the tar bases are liberated by treatment with caustic followed by distillation. The composition of this product is typically 92% quinoline and 5% iso-quinoline by weight with smaller amounts of all monomethylquinolines, 2,8-dimethylquinoline, and some homologues of iso-quinoline. 

The simplest member of the quinoline family is quinoline itself. It is a hygroscopic, yellowish oily liquid that is slightly soluble in water, soluble in alcohol, ether, carbon disulfide, and readily soluble in many other organic solvents. It can be obtained through the distillation of coal tar [2]. Quinoline can be prepared from aniline with acrolein under heated sulfuric acid (the Skraup synthesis [3-6], shown in Scheme 1) [ 1]. Isoquinoline was also isolated from coal tar in 1885 [2]. Both of these bases have been known about for a long time. 

Polycyclic aromatic nitrogen compounds, such as quinoline, indole, acridine, and carbazole, are the main nitrogen-containing compounds in oil fractions, and monocyclic pyridine and pyrrole as well as anilines are present in coal tar (Scheme 11). Saturated cyclic amines are found as products of ring hydrogenation of the compounds shown in Scheme 11 after HDN. Aliphatic amines are rarely found in fuels and only in low concentrations after HDN since their nitrogen atoms are easily removed. 

Coal-tar creosote is a mixture of aromatic hydrocarbons containing appreciable amounts of tar acids and bases (up to about 5% of each), and has a boiling range between 200 and 355°C. The important hydrocarbons present include fluorene, anthracene, phenan-threne, and some naphthalene. The tar acids are mainly phenols, creosols, xylenols, and naphthols the tar bases consist of pyridines, quinolines, and acridines. 

Quinoline is a colorless liquid, b.p. 239°, with a characteristic odor. It possesses the properties of a tertiary amine base forming salts as pyridine does. It is present with the latter in coal tar and in bone oil but is usually not obtained from these sources being prepared by Skraup s synthesis. 

Runge, F. F., (1795-1867) rediscovered aniline in coal tar oil in 1834, but named it kyanol, because a bright blue color appeared whenever it was mixed with a bleaching powder (chloride of lime)11. Note that in his pioneer work, Runge also discovered, for the first time, phenol (called then carbolic acid ), pyrrole, quinoline, naphthalene, rosolic acid and some other bases12. 

Cram and Allinger employed in place of the Lindlar catalyst a palladium-on-barium sulfate catalyst poisoned by synthetic quinoline (quinoline from coal tar was unsatisfactory). Thus on hydrogenation of dimethyl 5-decynedioate (I) in methanol the mildly exothermal reaction ceased abruptly after 20 min. with uptake... 

Pitch, product of coal tar distillation Pulp colors, organic Quinoline dyes Resorcinol Scarlet 2 R lake Stilbone dyes Styrene... 

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