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JEE Main levelOne or more correct optionsDifficulty 2 of 3o4119

2-Bromo-2-methylbutane is warmed in ethanol with no added base. Which statements are correct?

  1. AThe reaction is first order in the halide.
  2. B2-Methylbut-2-ene is the major alkene.
  3. C2-Ethoxy-2-methylbutane is formed as a competing SN1 product.
  4. DDoubling the concentration of added doubles the rate of the E1 path.

Answer: A, B, C

E1 and SN1 share the rate-determining ionisation to the tertiary cation, so the rate is first order and an ether accompanies the alkenes. Saytzeff elimination gives 2-methylbut-2-ene as the major alkene. In E1 the rate is independent of base concentration, so the last statement is false.
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