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JEE Main levelSingle correct optionDifficulty 2 of 3o4238

The compound shown is heated with sodium ethoxide in ethanol (E2). Which structure is the major alkene?

  1. AStructure A
  2. BStructure B
  3. CStructure C
  4. DStructure D

Answer: C

The compound is cis-1-bromo-2-methylcyclohexane. In the chair with bromine axial the methyl group is equatorial, so the hydrogen on C-2 is axial and anti-periplanar to bromine. Anti elimination toward C-2 gives the Saytzeff alkene 1-methylcyclohexene as the major product.
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