18.2 : ベンジル位での反応: 酸化と還元

Any carbon bonded to a benzene ring is called a benzylic carbon, and the attached hydrogens are called benzylic protons or hydrogens.

Benzene is inert to most strong oxidizing agents and is reduced only under harsh conditions.

However, the benzylic position is susceptible to oxidation and reduction.

Typical alkenes and alkynes at the benzylic position can be selectively reduced, while the benzene ring and the carbonyl groups remain unaffected.

Further, most alkylbenzenes can be readily oxidized to benzoic acid, irrespective of the alkyl chain length.

Notably, substituents like halogen and nitro groups remain unaffected.

If more than one alkyl side chain exists, each gets oxidized to a carboxylic acid group.

However, in the absence of a benzylic hydrogen, oxidation does not occur.