Potassium permanganate hydrazines

Effluents from conventional oxidations with classical stoichiometric inorganic oxidants, such as potassium dichromate and potassium permanganate, are very difficult to process and represent out-of-date chemistry. Replacement of conventional oxidations with catalytic oxidation using inexpensive and environmentally acceptable air as the oxidant is crucial. The same applies to hydrogenations using hydrides or the Wolf-Kizhner method with hydrazine. These methods of hydrogenation involve amounts of deleterious effluents and should be avoided. 

Chemical/Physical. Reacts with strong acids forming water-soluble salts. Also reacts with potassium permanganate forming tetraphenyl hydrazine (Zbozinek, 1984). In water, diphenylamine reacted with OH radicals at a rate of 4.9 x lO /M-h at 25 °C (Armbrust, 2000). 

A -Aryl substituents which are activated by nitro groups can be removed by nucleophilic di.splacement of the triazolyl anion by potassium hydroxide or by hydrazine. Oxidative removal of a p-aminophenyl substituent by potassium permanganate has also been reported. ... 

Alkylthio com ounds 16 (R = Ph) are oxidized by 30% hydrogen peroxide,or by potassium permanganate to the corresponding A -imidaz-olin-5-one sulfuryl chloride transforms disulfide 19 into 24. Alkylthio groups are not displaced by hydrazine ... 

Tetrazines (39) are readily attacked by nucleophiles such as ammonia or hydrazine. If the tetrazine is unsubstituted at position 6, 6-amino adducts (97) can be oxidized by potassium permanganate to give the 6-amino-l,2,4,5-tetrazines (98) (81JHC123, 81JOC5102, 81JOC3805). 

Extraction of the elemental form of bromine is used to separate short-lived bromine activities from fission products. Potassium chlorate in 8 N nitric acid solution (255)s potassium permanganate in nitric acid solution (106,248), and a bromlde-bromate-hypofchlorite mixture in acidic solution (247) have been used as the oxidizing agent. The bromine is extracted into carbon tetrachloride and can be back-extracted into the aqueous solution by reducing agents, such as potassium nitrate (255)> hydrazine hydrochloride (106,248), or sodium hydrosulphite (106). 

Disubstituted-l,3,4-oxadiazoles (xx) were prepared by the oxidation of l-aroyl-2-arylidine hydrazines (xix) with potassium permanganate on the surface of silica gel as well as in mixtures of acetone and water under microwave irradiation [27]. 

The reaction of 9-ethylcarbazol-3-carbaldehyde (xxxiii) with aroylhydrazines (xxxiv) under microwave condition gave the intermediate, l-aroyl-2-(9 -ethyl-carbazol-3 -yl-methylidene) hydrazines (xxxv). The further treatment of xxxv with potassium permanganate in DMF under microwave irradiation afforded the 2-aryl-5-(9 -ethylcarbazol-3 -yl)-l,3,4-oxadiazoles (xxxvi) in excellent yields [35]. 

Diamino-2-phenyltriazole and nitrosobenzene, stirred in an emulsion of benzene and 12 N sodium hydroxide, gave 4-amino-2-phenyl-5-phenylazotriazole (60°C, 10 min, 72%) (70BCJ3587). Potassium permanganate in dilute acetic acid oxidized 4-amino-3,5-diphenyltriazole to 3,3, 5,5 -tetraphenyl-4,4 -azotriazole (25 °C, 30%). This product, stirred with hydrazine hydrate and palladized carbon in chloroform, gave 4-amino-3,5-diphenyltriazole (25°C, 1 hr, 91%) (70JOC2215). 

Unsubstituted 1,2,4,5-tetrazine is attacked by ammonia or hydrazine to give 6-aminodihydro adducts, which can be oxidized with potassium permanganate to yield the 6-amino-l,2,4,5-tetrazine (84MI5). 

While oxidative amination of 1,2,4,5-tetrazines 1 occasionally proceeds with high yield (18-81%) to give l,2,4,5-tetrazin-3-amines 2,17 the Chiehibabin hydrazination of 1 affords hydrazines 3 in 9-15% yield. For the oxidative amination ammonia and primary amines are used while for the Chiehibabin hydrazination only hydrazine itself is used. The oxidizing agent of choice is potassium permanganate. 

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