Past exam of the chemistry course of the year 1 of the natural sciences course of the University of Cambridge / 2024 / Paper 1 / 3 / c / i

The alcohol is oxidized to cyclohexanone through an alkyl hypochlorite intermediate. Acid converts hypochlorite into electrophilic hypochlorous acid. The alcohol oxygen attacks chlorine, with acid-assisted proton transfers and loss of water giving the O–Cl derivative ${\mathrm{R}}_2\mathrm{CH}-\mathrm{O}-\mathrm{Cl}$.

A base such as acetate then removes the hydrogen attached to the carbinol carbon. The three coupled electron-pair motions are: base → H; C–H → C–O to form C=O; and O–Cl → Cl to release chloride. The resulting carbonyl is cyclohexanone. This is an elimination-like oxidation of the hypochlorite ester: the original alcohol oxygen becomes the ketone oxygen, while loss of its O-bound H and the carbinol C-bound H effects the net oxidation.