8-Hydroxyquinoline salts

Under an inert atmosphere, prepare a suspension of sodium hydride (0.96 g, 20 mmol [50 per cent in mineral oil]) in dry THF (50 mL) in a 250 mL twonecked round-bottomed flask fitted with a reflux condenser and pressure equalized addition funnel. Stir for 30 min under an inert atmosphere. Slowly add a solution of 8-hydroxyquinoline (2.90 g, 20 mmol) in dry THF (50 mL) to this through the addition funnel. Make up a solution of triethylene glycol ditosylate, 2, (4.60 g, 10 mmol) in dry THF (50 mL), ensuring that no solids remain (filter if necessary) or the addition funnel may become blocked. Once the effervescence subsides following the formation of the sodium 8-hydroxyquinolinate salt, add the ditosylate solution and reflux for 24 h. After 24 h, allow the solution to cool to room temperature, filter off the precipitated sodium tosylate and remove the THF by rotary evaporation. Dissolve the residue in dichloromethane (30 mL) and wash with distilled water (3 x 30 mL). Dry the organic phase over anhydrous sodium sulphate, filter and remove dichloromethane by rotary evaporation to give the crude product, l,9-bis(8-quinolinyloxy)-3,6-dioxanonane (4) as a pale brown oil. Further purification may be afforded by column chromatography (silica, elute with acetone/dichloromethane). 

Hydroxyquinoline salt, Ilentazol, Colitiazolo. Yellow crystals from dil methanol, dec ahove 220°. Split into its components by dil acids. 

Traditionally, antibacterial properties have been imparted to textile materials by chemically or physically incorporating chemical agents onto fabrics by means of coating processes. After World War II, the fungicides used on cotton fabrics were compounds such as 8-hydroxyquinoline salts, copper naphthenate, copper ammonium... 

Copper quinolinolate (oxine copper) is the chelate of divalent copper and 8-hydroxyquinoline and shares most of its market with copper naphthenate, which is a complex copper salt of mixed naphthenic acids. The principal uses are in wood treatments and some military textiles, where the green color is not objectionable. Copper naphthenate has an odor but is cheaper than oxine. Both copper naphthenate and 2inc naphthenate have performed well in environment tests, with exposure to soil above-ground, as well as concrete (33). 

Direct. Some radionucHdes are packaged in solution for direct sampling (qv) via a septum and injection into the patient. GalHum-67 is a marker of inflammation, infection, and various tumor types. Its half-life is 78.3 h and it is suppHed as the gallium citrate salt. Indium-111 chloride is suppHed for the labeling of white blood ceUs. The In chloride is mixed with oxine (9-hydroxyquinoline) to form a lipophilic, cationic In oxine complex, which enters the white blood ceU. The complex dissociates within the ceU, and the cationic In " ion is trapped within the ceU, owing to its charge. 

Traces of calcium can be removed from solutions of sodium salts by precipitation at pH 9.5-10 as the 8-hydroxyquinolinate. The excess 8-hydroxyquinoline acts as a collector. 

Until recent years the only syntheses of 3-hydroxy quinoline involved multistep processes, the last step of which consisted of the conversion of 3-aminoquinoline to 3-hydroxyquinoline via the diazonium salt. " Small quantities of quinoline have been oxidized to 3-hydroxyquinoline in low yields by using oxygen in the presence of ascorbic acid, ethylenediaminetetraacetic acid, ferrous sulfate, and i)hosi)halc buffer. The decarboxylation of 3-hydroxycinchoninic, acid in boiling nitrobenzene has been re-... 

In 1975, Weber and Vogtle showed that open-chained polyethers, 2,6-pyridine-dimethanol, and ortho-xylene derivatives terminated in an 8-quinolinyl group could form stable, 1 1, crystalline complexes with a variety of metal salts. The podands were prepared from 8-hydroxyquinoline and the corresponding dihalides. A typical example is shown in Eq. (7.10). 

Among the nucleophilic processes available for introduction of bromine to quinolines are reactions of the diazonium salts (87JHC181) and syntheses based on hydroxyquinolines or quinolones (91M935) (Scheme 36). The former processes are especially useful for making 5-, 6-, 7-, and 8-bromo derivatives. Halogen-halogen exchange reactions have also been reported, but they are not common. When perfluoroquinoline was heated... 

Nitrates and nitrites are first reduced to nitrosyl chloride with thionyl chloride. The volatile nitrosyl chloride then reacts with 4-aminobenzenesulfonic acid to yield a diazonium salt that then couples with 8-hydroxyquinoline to form a colored azo compound. Hence, the coupling reagent is applied to the chromatogram first. 

The list ends here other heterocycles have failed to gain significance as coupling components for diazonium salts. The only exception is 2,4-hydroxyquinoline, which is used as a starting material for a copper complex pigment (Sec. 2.10.1.1). 

Potassium salt of ethyl 7-chloro-6-fluoro-4-hydroxyquinoline-3-carbox-ylate (759, R = Cl, R1 = F) was isolated in pure form from a mixture of isomeric ethyl 5-chloro-6-fluoro- and 7-chloro-6-fluoro-4-hydroxyquino-line-3-carboxylates (758 and 759, R = Cl, R1 = F) by heating in DMF in the presence of an excess of potassium carbonate (89USP4868305). 

SWV has been applied to study electrode reactions of miscellaneous species capable to form insoluble salts with the mercury electrode such as iodide [141,142], dimethoate pesticide [143], sulphide [133,144], arsenic [145,146], cysteine [134, 147,148], glutathione [149], ferron (7-iodo-8-hydroxyquinolin-5-sulphonic acid) [150], 6-propyl-2-thiouracil (PTU) [136], 5-fluorouracil (FU) [151], 5-azauracil (AU) [138], 2-thiouracil (TU) [138], xanthine and xanthosine [152], and seleninm (IV) [153]. Verification of the theory has been performed by experiments at a mercury electrode with sulphide ions [133] and TU [138] for the simple first-order reaction, cystine [134] and AU [138] for the second-order reaction, FU for the first-order reaction with adsorption of the ligand [151], and PTU for the second-order reaction with adsorption of the ligand [137]. Figure 2.90 shows typical cathodic stripping voltammograms of TU and PTU on a mercuiy electrode. The order of the... 

Oxidation of appropriate mono- and di-hydroxyquinolines leads to quinones. This can be achieved by a variety of oxidizing agents including chromic acid and Fremy s salt (dipotassium nitrosodisulfonate, (KS03)2N0-) (67CB2077, 67CB2918). Examples are shown in Scheme 92. 9-Acridonequinones result from analogous oxidations of dihydroxy-9-acridones. 

The specific gravity of an 80% solution of hydrogen peroxide is 1.34. The solution is fairly stable at room temperature and decomposes only at an elevated temperature (the stability of hydrogen peroxide will be descussed later). To increase the stability of this solution, stabilizing substances such as phosphoric acid and its salts or 8-hydroxyquinoline were added. 

Chemical interference is caused by any component of the sample that decreases the extent of atomization of analyte. For example, SO and PO hinder the atomization of Ca2+, perhaps by forming nonvolatile salts. Releasing agents are chemicals that are added to a sample to decrease chemical interference. EDTA and 8-hydroxyquinoline protect Ca2+ from the interfering effects of SO and PO. La3+ also can be used as a releasing agent, apparently because it preferentially reacts with PO and frees the Ca2+. A fuel-rich flame reduces certain oxidized analyte species that would otherwise hinder atomization. Higher flame temperatures eliminate many kinds of chemical interference. 

D is found in compounds like quinolyl esters of N-substituted dithio-carbamic acids. A wide variety of compounds containing the quinoline system are herbicides. Derivatives and salts of 8-quinolinecarboxylic acid as well as quinolyl carbamates are each useful insecticides. The copper salt of 8-hydroxyquinoline is an effective fungicide. 

Terminally metallizable dyes (30) are obtained by the interaction of a diazonium salt and a coupling component containing a chelating system, for example salicylic acid, catechol, salicyl-aldoxime or 8-hydroxyquinoline, and their coordination chemistry is typical of these compounds. Such dyes were rarely used as preformed metal complexes but were usually applied to cotton and then converted to their copper complexes on the fibre to improve their fastness to wet treatments. A typical example is the blue dyestuff (31). 

Hydroxyquinoiine Chinosol (K salt of ethereal sulfate of 8-hydroxyquinoline) or P A. K salt -83.8 130... 

An analogous reaction took place with some 6-substituted-2-methyl-4-quinolones and [hydroxy(tosyloxy)iodo]benzene [162] and also between 5-nitro-7-hydroxyquinoline and (diacetoxyiodo)benzene [163]. Depending on the solvent or the presence of alkali, either the iodonium salt or the 1,4-dipole could be isolated. 

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