Oxidation of aromatic carbon atom ||PharmaEasyNotes||@Pharmacy ||Medicin...

March 16, 2021

Oxidation of aromatic carbon atom

Aromatic hydroxylation refers to the mixed-function oxidation of aromatic compounds (arene)  to their corresponding phenols (arenol).

The reaction proceeds via the formation of reactive intermediate arene oxide or arene epoxide, which results in multiple reactions.

(i) Arene oxide rearranges, rapidly and spontaneously to arenol by an intermolecular hybrid migration called NIH shift.

(ii) Nucleophilic attack of water on the epoxide by a microsomal enzyme called epoxide hydrase yield inactive trans dihydro diol metabolite.

(iii) Nucleophilic ring opening by GSHS -S- transferase to glutathione adduct.

(iv) Because of electrophilic and reactive nature, arene oxide may also react with nucleophilic functionalities present in biomacromolecules. Such reaction leads to modify protein, DNA, and RNA structure that causes serious toxicity.



(Did you Know)
-An arene or aromatic hydrocarbon is a hydrocarbon with alternative double and single bonds between carbon atoms forming rings.
Hydroxylation describes a chemical process that introduces a hydroxyl group into an organic compound.
Oxidation is the loss of electrons and gain of oxygen.
Reduction is the gain of electrons.
An NIH shift is a chemical rearrangement where a hydrogen atom on an aromatic ring undergoes an intramolecular migration primarily during a hydroxylation reaction. This process is also known as a 1,2-hydride shift.
An epoxide is a cyclic ether with a 3 atom ring.
Arene oxide- In chemistry, an arene oxide is an epoxide of an arene.
Two important families of arene oxides are benzene oxides and naphthalene oxides as these 
are intermediates in the oxidative degradation of benzene and naphthalene two common pollutant.
Pollutant- A substance that pollutes air, rivers etc.