Ferric chloride with oxygen

Mercaptoimidazoles resemble the hydroxy compounds in that they exist in the thione tautomeric forms. The thione group is readily removed with nitric acid,461 ferric chloride,462 oxygen in the presence of Pt-C catalyst,460 nickel boride,463 or, most commonly, Raney nickel.118,460... 

HCl gas reacts with metal oxides to form chlorides, oxychlorides, and water. Therefore, all the steel equipment should be pickled to remove the oxide scales before it is put in service. Because oxidi2ing agents in the HCl gas such as oxygen or chlorine significantly affect the corrosion rate, it is essential that the operating temperature of the steel equipment be kept below the temperature (316°C) at which ferric chloride is vapori2ed from the metal surface. 

Neutral aqueous salt solutions react slowly with tin when oxygen is present but oxidizing salt solutions, such as potassium peroxysulfate, ferric chloride and sulfate, and aluminum and stannic chlorides dissolve tin. Nonaqueous organic solvents, lubricating oils, and gasoline have Httle effect. 

Chlorine and bromine add to benzene in the absence of oxygen and presence of light to yield hexachloro- [27154-44-5] and hexabromocyclohexane [30105-41-0] CgHgBr. Technical benzene hexachloride is produced by either batch or continuous methods at 15—25°C in glass reactors. Five stereoisomers are produced in the reaction and these are separated by fractional crystallization. The gamma isomer (BHC), which composes 12—14% of the reaction product, was formerly used as an insecticide. Benzene hexachloride [608-73-17, C HgCl, is converted into hexachlorobenzene [118-74-17, C Clg, upon reaction with ferric chloride in chlorobenzene solution. 

For operations producing 30,000 tons or less of copper annuaHy, hydrometaHurgy offers an alternative to smelting that avoids problems associated with sulfur dioxide recovery and environmental controls. Techniques include the Anaconda oxygen—ammonia leaching process, the Lake Shore roast-leach-electrowin process, and ferric chloride leaching processes for the treatment of copper sulfides. AH the facHities that use these techniques encountered serious technical problems and were shut down within a few years of start-up. 

Very little is known concerning the simple, monocyclic 3-hydroxy-furans (cf. reference 15). Both the oxo and hydroxy forms of the substituted 3-hydroxyfurans 26 and 27 (R = H, CcHn) have been isolated/ but the individual tautomers slowly undergo interconversion. The enol forms give a positive reaction with ferric chloride, react rapidly with bromine, and form a peroxide with oxygen. From chemical evidence, the benzo derivatives of 3-hydroxyfuran, 28 and 29, appear to exist predominantly in the oxo form, and this is further supported by ultraviolet spectral data. Stefanye and Howard- ... 

The first addition step—specifically, the direct catalytic chlorination of ethylene [Eq. (6.40)]—is almost always conducted in the liquid phase.188-190 272 273 1,2-Dichloroethane is used as solvent with ferric chloride, an efficient and selective catalyst. Ionic addition predominates at temperatures of 50-70°C. The conversion is usually 100% with 1,2-dichloroethane selectivity higher than 99%. The primary byproduct is 1,1,2-trichloroethane, believed to be formed by subsequent radical chlorination of 1,2-dichloroethane. A low amount of oxygen (below 1%), therefore, is added to the chlorine feed to suppress radical side reactions. 

Careful examination of the oxygen-uptake curves with ferric acetylacetonate or ferric chloride present, failed to reveal an induction period... 

When an alkali perarsenate is added to aqueous solutions of metallic salts, precipitates containing active oxygen are obtained thus salts of the alkaline earths, zinc, cadmium, silver, mercurous mercury, lead and bismuth yield white precipitates, mercuric salts give red precipitates, copper blue, manganese pink, nickel greenish-white and ferrous salts bluish-green. With auric chloride oxygen is liberated, and with ferric chloride feme hydroxide is precipitated. 

Hydrazoic acid and permanganate mutually reduce each other with the evolution of a mixture of nitrogen and oxygen. The acid and its salts give with ferric chloride solution a deep red coloration, similar to tnat produced by thiocyanates, but the color is discharged by hydrochloric acid. 

Sulfoxides were found in the weak bases and the neutral Lewis bases. The presence of sulfoxides in the bases is explained by their weakly basic character (21). The presence of sulfoxides in the neutral Lewis bases probably results because the sulfur-oxygen bond is extremely polar and may complex with ferric chloride. Elemental analysis of the subfractions (discussed later) suggests that the sulfoxides are concentrated by the separation scheme and are not oxidation products that occur after the separation. The totals which are in excess of 100% reflect the degree of multifunctionality as well as possible errors in VPO molecular weight. 

E. P. Alvarez 2 found that the pemitrates react with soln. of lead acetate (white precipitate), silver nitrate (white precipitate), mercurous nitrate (white precipitate with rapid decomposition), mercuric chloride (red precipitate), copper sulphate (blue precipitate), zinc and cadmium sulphates (white precipitate), bismuth nitrate (white precipitate), gold chloride (slight effervescence and escape of oxygen), manganous chloride (pink precipitate), nickelous chloride or sulphate (greenish-white precipitate), cobaltous nitrate and chloride (pink precipitate), ferrous sulphate (green or bluish-green precipitate), ferric chloride (red ferric hydroxide), and alkaline earth chlorides (white precipitates). The precipitates are all per-salts of the bases in question. 

Regioselective debenzylation can be achieved by treatment with Lewis acids such as ferric chloride and S11CI4 or under acetolysis conditions with acetic anhydride and sulfuric acid, and several examples are depicted in Scheme 2.3.9 Acetolysis results in cleavage of the most acid-sensitive benzyl group. In general, primary benzyl ethers can be selectively acetolysed in the presence of secondary benzyl ethers. The regioselectivity of the reaction can be explained as follows sulfuric acid protonates acetic anhydride followed by the formation of an acetyl ion and acetic acid. The acetyl ion reacts with the sterically most accessible oxygen which is at... 

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