Oxidation of a side chain

Oxidation of a side chain by alkaline permanganate. Aromatic hydrocarbons containing side chains may be oxidised to the corresponding acids the results are generally satisfactory for compounds with one side chain e.g., toluene or ethylbenzene -> benzoic acid nitrotoluene -> nitrobenzoic acid) or with two side chains e.g., o-xylene -> phthalic acid). 

By the oxidation of a side chain, provided the molecule contains no other groups (e.g., amino NH, and hydroxyl OH) which are affected by oxidising agents, for example ... 

It is expected and has been clarified experimentally that there are two reaction pathways depending on which amino group is oxidized first and that the oxidation of a side-chain -amino group and an a-aminc group leads to a (S)-L-isomer and racemate, respectively. The apparent catalyst dependence, L-isomer from Ti02 and... 

From Hydrocarbons, Friedel-Craft.—The aromatic hydrocarbons yield ring carboxy acids by other reactions than those effecting oxidation of a side chain. Carbon dioxide may be introduced directly into a benzene ring, thus converting a hydrogen into.carboxyl. This may be accomplished in the presence of aluminium chloride, Friedel-Craft reagent. 

The oxidation of pyridines to pyridones ° and the selective oxidation of a side-chain in aUcyl-pyridines and other azines, have been well studied. ... 

Isoeugenol to Vanillin. The formation of vanillin from eugenol is an example of an oxidation of a side chain to an aldehydic group in which it is convenient to protect one substituent against oxidation. Eugenol obtained from oil of cloves is heated with an alkali such as sodium hydroxide to convert it to isoeugenol, the hydroxyl group is protected by acetylation, and the substance is oxidized and then saponified to vanillin. 

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