Dihydroxylation of Alkenes
Cis-dihydroxylation of Alkenes: Proof of Mechanism
Hydroxylation of cyclohexene with osmium tetroxide or potassium permanganate exclusively gives cis-cyclohexan-1,2-diol with potassium permanganate.
This is proof that the permanganate ion attacks the alkene only from one side, resulting in the exclusive formation of cis diols .