Potassium mono-oxide

The oxidation of fluorinated derivatives, which requires chromium trioxide and hot, fuming nitric acid, usually stops at the mono-sulfone stage,although 2,2,4,4-tetrafluoro-l,3-dithietane is converted directly to the disulfone by treatment with chromium trioxide and boiling, fuming nitric acid. The conversion of 2,2,4,4-tetrachloro- or 2,2,4,4-tetrabromo-dithietane to the disulfone may be effected by oxidation to the monosulfone with potassium permanganate followed by treatment which chromium trioxide- nitric acid. Potassium permanganate oxidizes the dimer of thiocyclohexanone to the disulfone in 78% yield. 

Dioxiranes are very efficient and versatile oxidants, which can be used as oxygen-transferring reagents for a large variety of reactions. They are readily available from suitable ketones and potassium mono-peroxysulfate (KHSO5, trade name Oxone ) in buffered solution. Dioxiranes can be used either generated in situ or as a solution in the parent ketone prepared in a former reaction. In the total synthesis of ZK-EPO (1), acetone-derived dimethyl dioxirane was used as 0.1 M solution in acetone. ... 

Cyclic vinyl epoxides are versatile building blocks (Table 11) which have been used in palladium-assisted routes to carbocyclic nucleosides. A formal synthesis of ( )-aris-teromycin101, the carbocyclic analog of adenosine, has been accomplished employing ni-tromethane as the nucleophile which serves as an acyl anion equivalent (Table 11. entry 2). The aldehyde is released by subsequent basic potassium permanganate oxidation. If nitromethane is used diluted in tetrahydrofuran, then a mixture of mono- and bis-alkylated product is formed. Whereas the alkylation of cyclohexenoxide with dimethyl malonate proceeds in a 1,4-crs fashion under palladium(O) catalysis, the 1.2-/ra/i.v-product is formed under basic conditions in the absence of the palladium(O) catalyst. 

The me.thods for the preparation of potassium mono-chlorochromate include the action of hydrochloric acid on potassium dichromate in aqueous solution/ the reaction of potassium chloride with chromium(VI) oxide in aqueous solution and the action of chromyl chloride on potassium chromate dissolved in water or glacial acetic acid. The last method is to be preferred, since it gives a good yield of the monochlorochromate of a fair degree of pimity. With the first or second method, the product often contains some greenish impurities. These impurities are probably produced by reduction of some of the chromate by hydrochloric add. 

Various 6- and 7-methyl- and 6,7-dimethyl-pteridines bearing either oxo or amino groups in the 2- and 4-positions can be oxidized to the corresponding carboxylic acids by alkaline potassium permanganate on heating. Various lumazine and pterin mono- and di-carboxylic acids have been prepared in this way (48JA3026, 78CB3790). 

Addendum. In a recent paper Bertho et al. have described a new process for the isolation of kurchi alkaloids. From the final residue a new base, C23H34N2, m.p. 129 5°, was isolated as the carbonate, m.p. 91° it provides the following salts B, 2HI, 2H2O, dec.) 174° B, 2HCIO4, 2.5H2O, m.p. 283°, and a mono-acetyl derivative, m.p. 254°. In a second paper Bertho, Schonberger and Kaltenbom describe further products obtained in the oxidation of conessine by chromic acid and by potassium permanganate. ... 

Mono-, di-, and trisubstituted olefins undergo osmium-catalyzed enantioselective dihydroxylation in the presence of the (R)-proline-substituted hydroquinidine 3.9 to give diols in 67-95% yields and in 78-99% ee.75 Using potassium osmate(VI) as the catalyst and potassium carbonate as the base in a tm-butanol/water mixture as the solvent, olefins are dihydroxylated stereo- and enantioselectively in the presence of 3.9 and potassium ferricyanide with sodium chlorite as the stoichiometric oxidant the yields and enantiomeric excesses of the... 

Condensation of 2-ethynylcyclohex-l-eneylcarbaldehyde 69 with an excess of acetone gave the ketone 544 Reaction of equimolar amounts of 85 and 86 in ethereal methanolic potassium hydroxide gave the ketone 87. Oxidative coupling of 87 under Glaser conditions afforded two separable isomeric bisdehydro[15]-annulenones 88 and 89. The mono-ds isomer 88 may have the structure 90 in which... 

All of the sulfone diols were able to form oligomers in the second step of the reaction sequence, the Ullmann ether synthesis. As with the synthesis of the mono(bromophenoxy)phenol products, two methods were used to form the dibromo materials. Method A used pyridine, potassium carbonate and cuprous iodide, while Method B employed collidine and cuprous oxide with the dibromobenzene and higher molecular weight diol (IV). The major difference between the syntheses of the mono(bromophenoxy)phenols described earlier and these lies in the stoichiometry of the reactions. In order to... 

Potassium Tetrachloro-dipyridino-iridite, [Ir "pv2Cl4]K, is formed in the same manner as the mono-pyridino-compound, but on longer heating. The substance occurs in two isomeric forms, one orange-yellow, the other red. On oxidation with chlorine or nitric acid, tetra-chloro-dipyridino-iridium, [Irrvpy2CI4], is produced. It is a crystalline body, and with potassium iodide yields potassium tetrachloro-dipyridino-iridite thus ... 

Reaction of an alkene with hot basic potassium permanganate (KMn04) results in cleavage of the double bond, and formation of highly oxidized carbons. Therefore, unsubstituted carbon atoms become CO2, mono-substituted carbon atoms become carboxylates, and di-substituted carbon atoms become ketones. This can be used as a chemical test (known as the Baeyer test) for alkenes and alkynes, in which the purple colour of the KMn04 disappears, and a brown Mn02 residue is formed. 

Unsubstituted carbon atoms are oxidized to CO2, and mono-substituted carbon atoms to carboxylic acids. Therefore, oxidation of 1-butyne with hot basic potassium permanganate followed by acidification produces propionic acid and carbon dioxide. 

Nitrosodisulphonic acid decomposes spontaneously into sulphuric acid, sulphur dioxide and nitric oxide. Its solution is rapidly decolorised on shaking with air or on mixing with hydrogen peroxide, per-mono- or perdi-sulphuric acid, nitric acid, chlorine or potassium chlorate. Most metallic oxides and carbonates decompose the solution, being converted into sulphates.7... 

Schmidt, Distelmaier, and Reinhard later applied the same oxidation technique to the elucidation of the structure of a di-O-methylene-D-glucose. After mono-O-acetylation, the derivative was oxidized at 95° by potassium permanganate, in dilute phosphoric acid, to give 6-0-acetyl-3,5-0-methyl-ene-D-glucofuranose 1,2-carbonate, the structure of which was subsequently proved. 

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