Cupric permanganate

Cupric permanganate, Cu(Mn04)2 8H20, is commercially available and oxidizes primary alcohols and aldehydes to acids, secondary alcohols to ketones, and sulfides to sulfones in very high yields [894]. 

Similar results are obtained when saturated and benzylic alcohols are stirred at room temperature or refluxed in dichloromethane with cupric permanganate octahydrate, Cu(Mn04)2 8H20. The octahydrate reacts faster than the anhydrous salt. Decanol and benzyl alcohol give 91 and 84% yields of decanoic acid and benzoic acid, respectively, at room temperature after 24 h [894. ... 

The immediate outcome of the Hantzsch synthesis is the dihydropyridine which requires a subsequent oxidation step to generate the pyridine core. Classically, this has been accomplished with nitric acid. Alternative reagents include oxygen, sodium nitrite, ferric nitrate/cupric nitrate, bromine/sodium acetate, chromium trioxide, sulfur, potassium permanganate, chloranil, DDQ, Pd/C and DBU. More recently, ceric ammonium nitrate (CAN) has been found to be an efficient reagent to carry out this transformation. When 100 was treated with 2 equivalents of CAN in aqueous acetone, the reaction to 101 was complete in 10 minutes at room temperature and in excellent yield. 

A SELECTIVE, HETEROGENEOUS OXIDATION USING A MIXTURE OF POTASSIUM PERMANGANATE AND CUPRIC SULFATE (3aS,7aR)-HEXAHYDRO-(3S,6R)-DIMETHYL-2(3H)-BENZOFURANONE (2(3H)-Benzofuranone, hexahydro-3,6-dimethyl-,... 

Sulphates of the alkali and alkaline earth metals, when heated with sulphur, are converted into sulphide, polysulphide and thiosulphate, with simultaneous formation of sulphur dioxide many other sulphates, e.g. those of copper, mercury, silver and lead, yield only sulphide.7 Other salts of the metals behave in a similar- manner, undergoing transformation into sulphides, the change being effected more readily with the salts of the heavy metals, many of which indeed react slowly with sulphur even at 100° C. in the presence of water.8 At 150° to 200° C. mercuric, stannic and ferric salts in aqueous solution are quantitatively reduced by sulphur mercurous, cupric, bismuth and lead salts arc slowly but quantitatively precipitated as sulphides. Nitrates, permanganates and iodates cause oxidation of the sulphur to sulphuric acid. 

Hydrogen trisulphide is much more easily combustible than the crude parent hydrogen polysulphide. Exposure to light tends to accelerate its decomposition. It slowly reduces concentrated sulphuric acid to sulphur dioxide, whilst on contact with dry silver oxide, cupric oxide, lead dioxide or mercuric oxide, it bursts into explosive combustion,2 a residue of the metallic sulphide being obtained. Many other metallic oxides and most salts bring about a less vigorous decomposition metals in the massive condition only react with it slowly. With potassium permanganate or dichromate the reaction is violent. 

Tropolone itself can be prepared in a number of ways, the most convenient of which involves oxidation of 1,3,5-cycloheptatriene with alkaline potassium permanganate. The yield is low but the product is isolated readily as the cupric salt ... 

Cupric sulfate-quinine-pyridine A solution that is 0.4% in cupric sulfate, 0.04% in quinine hydrochloride, and 4% in pyridine in water is sprayed on the plate followed by a 0.5% aqueous potassium permanganate solution. A variety of colors (white, yellow, violet) are detected on the chromatogram. 

Preparations of the required activity were also obtained when a hot solution containing cupric and manganous sulfates in the molar ratio of 3 2 was treated with potassium permanganate. 

The oxidation of silanes also can be accomplished by solutions of potassium permanganate, mercuric salts, ferric compounds, and cupric salts. Plain water also will oxidize the silicon-hydrogen bond in the presence of hydroxyl ions as catalysts 6... 

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