Potassium permanganate properties

Chakactkrisation of Unsaturatkd Aliphatic Hydrocarbons Unlike the saturated hydrocarbons, unsaturated aliphatic hydrocarbons are soluble in concentrated sulphuric acid and exhibit characteristic reactions with dUute potassium permanganate solution and with bromine. Nevertheless, no satisfactory derivatives have yet been developed for these hydrocarbons, and their characterisation must therefore be based upon a determination of their physical properties (boiling point, density and refractive index). The physical properties of a number of selected unsaturated hydrocarbons are collected in Table 111,11. 

Chemical Properties. The most significant chemical property of L-ascorbic acid is its reversible oxidation to dehydro-L-ascorbic acid. Dehydro-L-ascorbic acid has been prepared by uv irradiation and by oxidation with air and charcoal, halogens, ferric chloride, hydrogen peroxide, 2,6-dichlorophenolindophenol, neutral potassium permanganate, selenium oxide, and many other compounds. Dehydro-L-ascorbic acid has been reduced to L-ascorbic acid by hydrogen iodide, hydrogen sulfide, 1,4-dithiothreitol (l,4-dimercapto-2,3-butanediol), and the like (33). 

Phaeanthine, C3JH42O0N2. (Item 8 list, p. 350.) This alkaloid was isolated by Santos.It has m.p. 210°, [a]u°° — 278° (CHCI3), yields a hydriodide, m.p. 268°, picrate, m.p. 263°, aurichloride, m.p. 170-1°, and a platinichloride, m.p. 280° (dec.), and contains four methoxyl and two methylimino groups. By the Hofmann degradation process it yields an optically inactive methine base A, m.p. 173°, which is oxidised by potassium permanganate in acetone to 2-methoxy-5 4 -dicarboxydiphenyl ether (p. 348). A comparison of the properties of phseanthine and tetrandrine by Kondo and Keimatsu indicates that these two alkaloids are optical antipodes, so that phseanthine will be represented by either (XXXIX) or (XL) as given on p. 348, 1 and of these two formula (R = Me) one must represent oxyacanthine methyl ether and the other berbamine methyl ether (centres of asymmetry d- and 1-) tetrandrine (centres of asymmetry both d-) and phseanthine (centres of asymmetry both 1-). 

Condensation of p-chlorobenzaldehyde with 3-mercaptopropionic acid in the presence of ammonium carbonate leads to the thiazi-none, 179. The reaction very probably proceeds by the intermediacy of the carbonyl addition product, I7S lactamization completes formation of the observed product. Oxidation of 179 to the sulfone by means of potassium permanganate in acetic acid gives chlormezanone (180), a minor tranquilizer with muscle-relaxant properties. 

They have also carried out the oxidation of selinene by means of ozone and potassium permanganate and have thus been able to establish that the regenerated selinene is not absolutely identical with the natural selinene. They are the first to record the existence of a hemi-cyclic-sesquiterpene this compound is termed pseudo-()3)-selinene. By passing a current of ozone into a solution of natural selinene (pseudo-( 8)-selinene). in acetic acid, there is obtained a diketone, CjjHogOj, which is purified by treatment with permanganate in acetone solution. Its properties are as. follows —... 

The constitution of the new compound was proved22 by the isolation of an acid XX after oxidation at low temperature with potassium permanganate in alkaline solution. This acid was converted to its diethyl ester (XXI), the melting point and other properties of which coincide with those of a compound synthesized by Fischer and Hussong.23... 

A method [62] has been described for the determination of down to 2.5pg kg-1 alkylmercury compounds and inorganic mercury in river sediments. This method uses steam distillation to separate methylmercury in the distillate and inorganic mercury in the residue. The methylmercury is then determined by flameless atomic absorption spectrophotometry and the inorganic mercury by the same technique after wet digestion with nitric acid and potassium permanganate [63]. The well known adsorptive properties of clays for alkylmercury compounds does not cause a problem in the above method. The presence of humic acid in the sediment did not depress the recovery of alkylmercury compounds by more than 20%. In the presence of metallic sulphides in the sediment sample the recovery of alkylmercury compounds decreased when more than lmg of sulphur was present in the distillate. The addition of 4M hydrochloric acid, instead of 2M hydrochloric acid before distillation completely, eliminated this effect giving a recovery of 90-100%. 

Known as crown ethers because of their crown-like shape, these ethers contain cavities that are ideal for forming complexes with metal ions. It is this property that allows ordinary salts to dissolve in organic solvents. For example, potassium permanganate is usually insoluble in benzene, but readily dissolves in benzene if [18]-crown-6 ether is added. This solution is useful because it allows oxidation with potassium permanganate to be carried out in organic solvents. The potassium ion (shown in green) is just the right size to fit into the cavity in the crown ether. 

The physical properties of many macrocyclic polyethers and their salt complexes have been already described. - Dibenzo-18-crown-6 polyether is useful for the preparation of sharpmelting salt complexes. Dicyclohexyl-18-crown-6 polyether has the convenient property of solubilizing sodium and potassium salts in aprotic solvents, as exemplified by the formation of a toluene solution of the potassium hydroxide complex (Note 13). Crystals of potassium permanganate, potassium Lbutoxide, and potassium palladium(II) tetrachloride (PdClj + KCl) can be made to dissolve in liquid aromatic hydrocarbons merely by adding dicyclohexyl-18-crown-6 polyether. The solubilizing power of the saturated macrocyclic polyethers permits ionic reactions to occur in aprotic media. It is expected that this [)ropcrty will find practical use in catalysis, enhancement of... 

Add a hydrogen peroxide solution to a potassium permanganate solution acidified with sulphuric acid. Comment on your observations. Write the molecular and electron equations of the reaction. What properties of hydrogen peroxide does this reaction indicate ... 

Pour bromine water, chlorine water, and acidified solutions of potassium permanganate and dichromate into separate test tubes. Pass a stream of hydrogen snlphide through all the tubes. What happens Write the equation of the reactions. What property of hydrogen sulphide is indicated by the occurring phenomena ... 

Add potassium permanganate and dichromate solutions respectively to two test tubes containing selenous acid solutions acidified with sulphuric acid. Heat the contents of the test tubes. What do you observe Write the equations of the reactions. What properties does selenous acid exhibit in this case ... 

Studying the Properties of Titanium(in) Compounds. Pour 2 ml of the titanium(III) sulphate solution prepared in the preceding experiment into each of two test tubes. Let one tube stand in the air. What is observed Add several drops of a potassium permanganate solution to the other tube. What happens Write the equations of the reactions. 

Uranium Compounds with Lower Oxidation States. Pour 5 ml of a uranyl nitrate solution into a test tube, add 1 ml of a 10% hydrochloric acid solution, and drop one or two small pieces of zinc into the tube. How can the change in the solution s colour be explained Pour the solution into three test tubes. Pour a potassium permanganate solution dropwise into one tube. What happens What properties do uranium(lV) compounds have ... 

Properties of Permanganates. 1. Put several potassium permanganate crystals into a test tube and heat them. What gas evolves Write the equation of the reaction. 

Preparation and Properties of Manganic Anhydride. (Perform the experiment in a fume cupboard, in the presence of your instructor ) 1. Triturate several potassium permanganate crystals into a powder and spill it into a small porcelain bowl. Use a pipette or glass tube to wet the salt with a few drops of a 96 % sulphuric acid solution. What forms ... 

Attempts to rearrange tne phenyl acid into the trane form by heating to 290° with fused alkali yielded a small amount of an isomeric acid. Tnis acid was unattacked by potassium permanganate and was probably the cls-phenyl cls-trans dlcarboxyllc acid not enough was at hand to Investigate its properties. 

The wetting properties of polyacetylene have been studied by Schonhom et al. 380) who measured a critical surface tension of 51 mN m 1, considerably higher than for other hydrocarbon polymers. This value was attributed to oxidation of the surface as no change was observed on further oxidation. Treatment of polyacetylene with aqueous potassium permanganate renders it hydrophilic, reduces the contact angle for water from 72° to 10° and renders the structure more water-permeable 381)... 

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