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JEE Main levelSingle correct optionDifficulty 2 of 3ap173

1-Methylcyclohexene undergoes hydroboration with in THF, followed by /. The major product is

  1. Acis-2-methylcyclohexan-1-ol (racemic, methyl and OH on the same face)
  2. B1-methylcyclohexan-1-ol
  3. Ctrans-2-methylcyclohexan-1-ol (racemic, methyl and OH on opposite faces)
  4. D3-methylcyclohexan-1-ol

Answer: C

Hydroboration is anti-Markovnikov and syn: boron goes to C-2 (the less substituted carbon) and H to C-1 on the same face. Oxidation replaces B by OH with retention, so the new H on C-1 and OH on C-2 are cis, which makes the methyl group on C-1 trans to OH.
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