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JEE Main levelSingle correct optionDifficulty 2 of 3o2017

1-Methylcyclohexene is treated with $BH X_{3} \cdot THF$ and then with $H X_{2} O X_{2} / NaOH$ . The major product is

Acis-2-methylcyclohexanol
B3-methylcyclohexanol
Ctrans-2-methylcyclohexanol (as a racemic mixture)
D1-methylcyclohexanol

Answer: C

Boron adds to the less substituted carbon C-2 and H adds to C-1, both from the same face (syn addition). Oxidation replaces B by OH with retention. The H on C-1 and the OH on C-2 are cis, so the

CH X_{3}

on C-1 and the OH on C-2 are trans. The product is trans-2-methylcyclohexanol, racemic.

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