Potassium permanganate, as oxidant

The oxidation of diethyl 3,6-hexanooxepin-4,5-dicarboxylate with a mixture of sodium periodate and potassium permanganate as oxidizing agent gives diethyl 3-[(formyioxy)methylene]-l 0-oxocyclodec-l-en-l,2-dicarboxylate (2) in 91 % yield.130 A minor modification of the reaction conditions gives two products 2 (35 %) and a product which retains the oxepin structure (23 %) identified as the same lactone described in Section 1.2.1.1.129... 

Oxidative alkylamination of pteridine and its 2-chloro, 7-aryl, or 7-/-Bu derivative, using an alkylamine (Alkyl = Et or t-Bu) and potassium permanganate as oxidant, gave the corresponding 4-alkylamino pteridines (Scheme 32) (82JHC1527, 86JHC843). 

Quinoxaline (235) has been easily aminated in liquid ammonia with excess potassium amide and potassium permanganate as oxidant (82JHC1285). The ratio of monoamino to diamino products can be altered by varying the reaction time prior to addition of the oxidant (Scheme 78). When potassium permanganate was added 5-10 min after 235 was added to liquid ammonia containing potassium amide, the yield of 2-aminoquinoxaline (236) was 53% and 2,3-diaminoquinoxaline(237) was 23%. However, if the oxidant was not added until 30 min had elapsed, the yield of 236 was 4% and that of 237 was 57%. 

Aliphatic nitro-compounds, as their nitronate anions, react with molybdenum peroxide, MoO5.py.HMPA, to give carbonyl compounds. Primary nitroalkanes give the carboxylic acid. A re-appraisal of potassium permanganate as oxidant for primary nitroalkane salts indicates this can be an excellent reagent for the preparation of aldehydes, particularly quaternary aldehydes. ... 

An early study of the attempted phase-transfer catalysed oxidation of dibenzyl sulphoxide to the sulphone using a variety of conditions and oxygen, periodate, hypochlorate and permanganate as oxidants showed that only potassium permanganate gave any of the required product, albeit in low yields. A further study, using Adogen 464 as... 

Jurka and Carter [50] have described an automated determination of down to O.lpg L 1 mercury in river sediment samples. This method is based on the automated procedure of El-Awady [51] for the determination of total mercury in waters and waste waters in which potassium persulphate and sulphuric acid were used to digest samples for analysis by the cold vapour technique. These workers proved that the use of potassium permanganate as an additional oxidizing agent was unnecessary. 

The vital application of potassium permanganate as a potential oxidizing agent in an acidic medium mainly rests on the reactions designated by the following equations ... 

The corresponding syzz-isomer was, on the other hand, prepared from the potassium permanganate-mediated oxidation of trifluorocrotonate 10, derived from -hydroxy-butyrate. In this procedure, the diol ester with syn relative configuration was the only product detected. After acetylation, syn-11 was employed as a substrate for the enzymatic resolution affording both (2S,3S)-11... 

Irreversible degradation of the porphyrin nucleus can be accomplished with oxidants such as chromium trioxide or potassium permanganate. As shown in Scheme 3, the products from the Cr03 reaction are maleimides, and this procedure has been used extensively for structure elucidation, and for tracking down the fate of isotopic labels in biosynthetic studies (B-75MI30702). In the absence of side chains such as formyl and vinyl, which are labile towards Cr03, it is possible to identify the various substituents on porphyrin subunits. 

Asymmetric phase-transfer catalyzed oxidation of olefin using sodium hypochlorite or potassium permanganate as metal anion sources is the typical example of this category. 

To prepare 2-aminopyridine by treatment of pyridine with potassium amide in liquid ammonia at —33 °C and using permanganate as oxidant was not successful. No reaction takes place under these conditions. The aromaticity of the pyridine ring is too high to allow nucleophilic amide addition. It was surprisingly observed that treatment of a solution of 3-nitropyridine in liquid ammonia (thus without the presence of potassium amide) with potassium permanganate, gave after work-up a mixture of... 

In the oxidative amination of quinoline, using potassium amide in liquid ammonia and permanganate as oxidant, it was found that the site of ami-nation is strongly depending on temperature. When the amination is carried out at — 65 °C 2-aminoquinoline is isolated (52%) 4-aminoquinoline is formed (with some 2-aminoquinoline) when the amination is performed at room temperature. By NMR spectroscopy it was unequivocally observed that at — 65 °C addition of the amide ion occurs at position 2 of the quinoline ring, yielding the a-adduct 2-amino-1,2-dihydroquinolinide, which under the conditions of the reaction remained stable. When warming up the solution this C-2 adduct irreversibly converts into the... 

The usual oxidising media, such as permanganates, bichromates, etc.,4 react instantaneously with ferrous salts, yielding in acid solution the normal ferric salts. Many methods for the quantitative determination of iron are based on these reactions. Thus, for example, with potassium permanganate the oxidation of ferrous sulphate proceeds as follows —... 

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