Question

$\begin{array}{ccc}& & C{H}_3\\ & & |\\ H& -& C\\ & & ||\\ H& -& C\\ & & |\\ & & C{H}_3\end{array}\underset{}{\overset{alkalineKMn{O}_4}{\to }}A$

Which is true about this reaction?

• A. A is meso 2, 3butandiol formed by syn addition
• B. A is meso 2, 3butandiol formed by anti addition
• C. A is a racemic mixture of d and l, 2, 3butandiol formed by anti addition
• D. A is a racemic mixture of d and l 2,3butandiol formed by syn addition

Answer 1

The correct option is A A is meso 2, 3butandiol formed by syn addition

The compound A is meso 2,3-butandiol formed by syn addition of two hydroxyl groups.
Alkaline $KMn{O}_4$. It is used for the dihydroxylation of C=C double bond.
Two hydroxyl groups are added on the same side of C=C double bond.