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JEE Main levelOne or more correct optionsDifficulty 2 of 3o2197

1-Methylcyclopentene is treated with and then . Which statements are correct?

  1. AThe carbon skeleton rearranges through a tertiary carbocation
  2. BThe new and bonds are on the same face of the ring
  3. CThe product is obtained as a single optically active enantiomer
  4. DThe product is trans-2-methylcyclopentan-1-ol

Answer: B, D

Boron adds to the less substituted carbon and H adds to the methyl-bearing carbon on the same face (syn), with no carbocation. OH replaces B with retention, so OH and are trans. Both enantiomers form equally, so the product is racemic.
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