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JEE Main levelOne or more correct optionsDifficulty 2 of 3o3258

The primary bromide shown is solvolysed in hot ethanol with no strong nucleophile. Select all correct statements.

  1. AMigration of a methyl group avoids a discrete primary cation
  2. B2-Methylbut-2-ene is among the products
  3. CThe main substitution product keeps the neopentyl skeleton
  4. DIt ionises faster than 2-bromo-2-methylpropane

Answer: A, B

The compound is neopentyl bromide. Ionisation is accompanied (or immediately followed) by a 1,2-methyl shift, so a discrete primary cation is not required. The tertiary cation formed can lose a proton to give 2-methylbut-2-ene. The main substitution product is the rearranged 2-ethoxy-2-methylbutane, not the unrearranged ether, and ionisation is much slower than for tert-butyl bromide. Correct: first two.
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