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Which of the following will undergo easy dehydrohalogenation on reaction with alc. KOH ? I.  2-chloropropane II.  chloroethane III.  2-chloro 2-methyl propane

Options

  1. AIII > I > II
  2. BI > II > III
  3. CIII > II > I
  4. DII > I > III

Correct answer

A. III > I > II

Step-by-step solution

This problem includes includes conceptual mixing of dehydrohalogenation and stability of alkene according to Sytzeff's rule. Student are advised to complete the elimination reaction first and then choose the correct stable product using Sytzeff's rule. Dehydrohalogenation reaction The Dehydrohalogenation reaction of alkyl halide occurs by removal of hydrogen and halogen from adjacent position. Sytzeff's rule : According to Sytzeff's rule, the more substituted alkene is formed in major amount due to

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