Benzyltriethylammonium permanganate

Warning Explosions with benzyltriethylammonium permanganate J. Graefe and R. Rienac-ker, Angew. Chem., Int. Ed. Engl., 22, 625 (1983). 

Benzyltriethylammonium permanganate has also been used for the mild oxidation of sulphoxides to sulphones at — 10 °C in methylene chloride in the presence of keto, amino and ester groups in > 65% yields142. 

Aluminium tetrahydroborate, Alkenes, Oxygen Benzeneseleninic acid, Hydrazine derivatives Benzyltriethylammonium permanganate Bis(4-hydroxyphenyl) sulfone... 

Aluminium chloride, Nitrobenzene, 0062 Ammonium hydrogen sulfite, 4545 Benzyltriethylammonium permanganate, 3617 Bis(4-hydroxyphenyl) sulfone, 3497 2-Chloro-5-nitrobenzenesulfonic acid, 2144 1,3 -Dichloro-5,5-dimethyl-2,4-imidazolidindione, 1865 f Dimethyl sulfoxide, 0921... 

EXPLOSIVELY UNSTABLE compounds [4, 6-9]. It has been reported that solid benzyltriethylammonium permanganate is considerably less stable than the tetra-butylammonium salt both compounds are sensitive to impact, but the benzyl-ammonium salt may explode violently at room temperature [4] and it is more readily handled by absorption on alumina [4]. 

Allyl and aryl ethers produce carboxylic esters in good yields (60-80%) upon oxidation by benzyltriethylammonium permanganate in dichloromethane [33], e.g. dibenzyl ether gives benzyl benzoate (80%). 

Primary and secondary alcohols are oxidized slowly at low temperatures by benzyltriethylammonium permanganate in dichloromethane primary alcohols produce methylene esters (60-70%), resulting from reaction of the initially formed carboxylate anion with the solvent, with minor amounts of the chloromethyl esters and the carboxylic acids. Secondary alcohols are oxidized (75-95%) to ketones [34] the yields compare favourably with those obtained using potassium permanganate on a solid support. 1,5-Diols are oxidized by potassium permanganate under phase-transfer catalytic conditions to yield 8,8-disubstituted-8-valerolactones [35] (Scheme 10.1). 

Ethers in which at least one group is primary alkyl can be oxidized to the corresponding carboxylic esters in high yields with ruthenium tetroxide.297 Cyclic ethers give lactones. The reaction, a special case of 9-16, has also been accomplished with CrO, in sulfuric acid.39" with benzyltriethylammonium permanganate,299 and with trichloroisocyanuric acid in the presence of an excess of water.300 In a similar reaction, cyclic tertiary amines (e.g., 28) can... 

Aluminium chloride, Nitrobenzene, 0062 Ammonium hydrogen sulfite, 4540 Benzyltriethylammonium permanganate, 3611... 

The relatively most frequent reaction is oxidation at the methinegroup giving tertiary alcohols as main products and secondary alcohols and ketones as minor products [902]. The hydroxylation occurs predominantly with retention of configuration [329, 620]. The oxidation of 3-ethylpentane with benzyltriethylammonium permanganate yields 24% of 3-ethyl-3-pen-tanol, 25% of 3-ethyl-2-pentanone, and 25% of 3-pentanone [902]. Under the same conditions, methylcyclohexane yields 72% of 1-methylcyclo-hexanol and 3% of 2-methylcyclohexanone [902]. 

On the other hand, potassium permanganate is frequently used to prepare carboxylic acids from both aliphatic [86S] and aromatic aldehydes [555]. High yields of carboxylic acids are also obtained by oxidation with tetrabutylammonium permanganate [599] or benzyltriethylammonium permanganate [903] (equation 350). Recently, doubts about the safety of work with quaternary ammonium permanganates have been raised [967]. 

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