Warm concentrated potassium permanganate (KMnO 4) will react with an alkene to form a glycol, and the KMnO 4 will can then easily cleave the glycol to give aldehydes or ketones.
Warm concentrated potassium permanganate (KMnO 4) will react with an alkene to form a glycol. Following this dihydroxylation, the KMnO 4 can then easily cleave the glycol to give aldehydes or ketones.