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JEE Main levelSingle correct optionDifficulty 2 of 3o4099

3,3-Dimethylbutan-2-ol is treated with in pyridine. The principal product is

  1. A2,3-dimethylbut-1-ene
  2. B2-chloro-3,3-dimethylbutane
  3. C3,3-dimethylbut-1-ene
  4. D2,3-dimethylbut-2-ene

Answer: C

POCl3 converts the OH into a dichlorophosphate leaving group, and pyridine removes a beta hydrogen in a concerted E2 step with no carbocation. The only beta hydrogens are on C-1, so 3,3-dimethylbut-1-ene is formed without methyl shift. With conc. the carbocation route would give 2,3-dimethylbut-2-ene.
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