CH₃ - CH₂ - CH = CH - CH₃ When oxidized with acidified KMnO₄ at 100^oC forms

${\mathrm{CH}}_3-{\mathrm{CH}}_2-\mathrm{CH}=\mathrm{CH}-{\mathrm{CH}}_3+4\left(\mathrm{O}\right)\underset{\mathrm{acid},{100}^{\circ }\mathrm{C}}{\overset{KMn{O}_4}{\to }}{\mathrm{CH}}_3{\mathrm{CH}}_2\mathrm{COOH}+{\mathrm{CH}}_3\mathrm{COOH}$
With hot and concentrated KMnO₄ solution the reaction is drastic. This leads to cleavage of both $\mathrm{\sigma }$ and $\mathrm{\pi }$ bonds in alkene. The resultant products are acids, ketones, carbon dioxide and water depending on the nature of double bond.