Oxidation reactions toluene agents

Ambulgekar et al. [30] investigated the oxidation of toluene using aqueous KMn04 as an oxidizing agent in the hydrodynamic cavitation reactor with an objective of optimization of the operating parameters. The reaction scheme can be depicted as follows ... 

Disproportionation. A chemical reaction in which a single compound serves as both an oxidizing and reducing agent such as the dealkylation of toluene to give benzene (the more reduced product) and xylene (the more oxidized product). 

Selective monoprotection of diols is moderately effective. Fluoride ion-promoted monoalkylation of tartrate diesters that have been activated as the stannylene acetal is an extremely effective method for the efficient monoalkylations of diols. An equimolar mixture of dimethyl tartrate (la) and dibutyltin oxide in toluene, heated under reflux to azeotropically remove the formed water, provides a stannylene acetal. The crude acetal in DMF is treated with cesium fluoride and then benzyl bromide to provide in 85% yield the dimethyl (2J ,37 )-2-0-ben-zyltartrate (421). Reaction of la with benzyl bromide and CsF in DMF proceeds to provide 421 in only 5% yield. Benzyl iodide is generally a better alkylating agent, providing 421 in 99% yield [147]. 

Supercritical CO2 is a non-polar, aprotic solvent and promotes radical mechanisms in oxidation reactions, similar to liquid-phase oxidation. Thus, wall effects might occur as known, e.g. from olefin epoxidation with 02 or H202 which may decrease epoxide selectivities. The literature covers the synthesis of fine chemicals by oxidation either without catalysts (alkene epoxidation, cycloalkane oxidation, " Baeyer-Villiger oxidation of aldehydes and ketones to esters ), or with homogeneous metal complex catalysts (epoxidation with porphyrins, salenes or carbonyls ). Also, the homogeneously catalysed oxidation of typical bulk chemicals like cyclohexane (with acetaldehyde as the sacrificial agent ), toluene (with O2, Co +/NaBr ) or the Wacker oxidation of 1-octene or styrene has been demonstrated. 

When the alkyl group is one oxidizable to COOH (19-11), cupric salts are oxidizing agents, and the OH group is found in a position ortho to that occupied by the alkyl group.This reaction is used industrially to convert toluene to phenol. 

Conversion of toluenes to the benzoic acid is also accomplished by anodic oxidation in acetic acid containing some nitric acid. It is not clear if this reaction involves the aromatic radical-cation or if the oxidising agents are nitrogen oxide radicals generated by electron transfer from nitrate ions [66, 67]. Oxidation of 4-fluorotoluene at a lead dioxide anode in dilute sulphuric acid gives 4-fluorobenzoic acid in a reaction which involves loss of a proton from the aromatic radical-cation and them in further oxidation of the benzyl radical formed [68]. 

HNS (7.5) can be prepared by many methods these include the reaction of nitro derivatives of toluene with benzaldehyde, the reaction of nitro derivatives of benzyl halogenides with alkaline agents by removing hydrogen halogenide, and the oxidation of nitro derivatives of toluene. 

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