Quinoline continued

The asymmetric hydrogenation of quinoline continues to be of interest. Li et al. reported the asymmetric hydrogenation of a variety of 2-substituted-quinolines to the corresponding tetrahydroquinolines using an Ir-catalyst with a BINOL-derived diphosphonite ligand... 

A = C9H7N 13551 C11H20O Quinoline (continued) Methyl a-terpineol ether 237.3 216.2 Nonazeotrope 256... 

The oxidation of appropriate alkylpyridines and quinolines continues to represent the most important process for the manufacture of nicotinic acid. All aspects of the field have seen continuing development, and a Czech review is available. A general developmental study comparing seven oxidizing agents on a quantitative basis has also appeared. ... 

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). 

A mixture of 26 parts of 3-carbethoxy-6,7-methylenedioxy-4-hydroxy-quinoline, 16 parts of sodium hydroxide and 50 parts of dimethylformamide is heated at 70° to 75°C for 2 hours, then 31 parts of ethyl iodide is added over 1 hour with continued heating and stirring. After an additional 3 to 4 hours of heating (at 70° to 75°C) and stirring, the mixture is diluted with 500 parts of water, refluxed for 3 to 4 hours, acidified with concentrated hydrochloric acid and filtered to yield 18 to 22 parts of 1-ethyl-1,4-dihydro-6,7-methylene-dioxy-4-oxo-3-quinoline-carboxylic acid, MP 309° to 314°C (decomposes). The analytical sample from dimethylformamide melts at 314° to 316°C (decomposes). 

Anhyd NH3(g) was bubbled through a stirring mixture of 6,7-di(phenylselanyl)naphthalene-2,3-dicarbo-nitrile (200 mg, 0.43 mmol), NaOMe (0.22 mmol) and 2-methoxyelhanol (5 mL) for 30 min. With continued NH3 introduction, the mixture was heated to 65 "C for 3 h. The solution was evaporated in vacuo. CuCl (21.8 mg, 0.22 mmol) and quinoline (5 mL) were added to the residue and refluxed for 2 h. MeOH was added and the precipitate was filtered, washed with acetone, CH2C12. and toluene yield 105 mg (51 %). 

In a flask was placed pyridine-2,3-dicarbonitrile (2.58 g, 20 mmol), Cu powder (0.32 g, 5 mmol) and quinoline (5mL). The suspension was stirred and heated to 212 C for 4h. Upon completion of the reaction, the mixture was suspended in MeOH and filtered. This solid was collected, was suspended in MeOH and stirred. The heavier unreacted Cu settled quickly and the solid was decanted off. This was continued repeatedly until the solid was removed from any unreacted Cu. The solid was filtered and dried at 195 C for 2 h yield 2.67 g (92 %). 

A two phase process, in which the feedstock (e.g., petroleum) was mixed with water and an organic solvent to improve denitrogenation of aromatic nitrogen compounds [102], led to an improvement of the process. Additionally, a surfactant was used to increase the interfacial area. Carbazole and quinoline and their alkyl derivatives were used as primary compounds for demonstration. The biocatalyst is used in resting stage and is continuously fed to the system to keep the reaction rate at an acceptable level. It was observed that quinoline was hardly removed under the conditions at which carbazole was decomposed and assimilated. 

Additions to quinoline derivatives also continued to be reported last year. Chiral dihydroquinoline-2-nitriles 55 were prepared in up to 91% ee via a catalytic, asymmetric Reissert-type reaction promoted by a Lewis acid-Lewis base bifunctional catalyst. The dihydroquinoline-2-nitrile derivatives can be converted to tetrahydroquinoline-2-carboxylates without any loss of enantiomeric purity <00JA6327>. In addition the cyanomethyl group was introduced selectively at the C2-position of quinoline derivatives by reaction of trimethylsilylacetonitrile with quinolinium methiodides in the presence of CsF <00JOC907>. The reaction of quinolylmethyl and l-(quinolyl)ethylacetates with dimethylmalonate anion in the presence of Pd(0) was reported. Products of nucleophilic substitution and elimination and reduction products were obtained . Pyridoquinolines were prepared in one step from quinolines and 6-substituted quinolines under Friedel-Crafts conditions <00JCS(P1)2898>. 

Deuterium gas experiments, continuous NMR and GC/MS analysis, in situ high-pressure NMR spectra and the isolation of some intermediates provided Fish with sufficient information to propose the mechanism shown in Scheme 16.16 for the hydrogenation of quinoline to THQ, catalyzed by [Rh(NCMe)3Cp ]2+ (40°C, 33 bar H2, CH2C12) [55]. 

Kido et al. [6] determined basic organic compounds such as quinoline, acridine, aza-fluorene, and their N-oxides in marine sediments found in an industrial area. The sediments were extracted with benzene by using a continuous extractor for 12h. Hydrochloric acid solution (IN) was added to the benzene extracts, and the mixture was shaken for 5min the acid layer separated from the benzene layer was made alkaline by the addition of sodium hydroxide, and the alkaline aqueous solution was extracted with diethyl ether the ether extracts were then dehydrated with anhydrous sodium sulphate and concentrated with a Kuderna-Danish evaporator. The concentrations were separated and analysed by gas chromatography-mass spectrometry and gas chromatography high-resolution mass spectrometry. 

By reacting quinoline first with benzoyl chloride and then with aqueous potassium cyanide, the corresponding Reissert compound is obtained. The reaction is normally carried out in one operation using a two-phase system plus a phase transfer catalyst. The N-benzoy group can then be removed by heating with sodium hydroxide solution, and the reaction is continued to hydrolyse the nitrile function to the acid ... 

The application of the dehydrogenation method for the preparation of 4//-cyclopenta[h]quinolines (39) can be seen in Scheme 8.49 The pseudoazulenes, however, continue to react with the chloranil. Thus, thialenes (28)... 

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