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JEE Main levelSingle correct optionDifficulty 2 of 3o3193

Cyclohexene oxide is treated with dilute aqueous $H X_{2} SO X_{4}$ . The product is

Aonly the $(1 R, 2 R)$ enantiomer of trans-cyclohexane-1,2-diol
Bracemic trans-cyclohexane-1,2-diol, i.e. an equimolar mixture of the $(1 R, 2 R)$ and $(1 S, 2 S)$ forms
Cmeso (cis) cyclohexane-1,2-diol
Dcyclohexane-1,1-diol

Answer: B

Water attacks the protonated epoxide from the side opposite the breaking

C - O

bond (anti opening), so the two OH groups end up trans. The achiral epoxide can be attacked at either carbon with equal probability, giving both enantiomers in equal amounts. The product is racemic trans-diol.

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