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Question
Explain the dehydrohalogenation reaction of 2-chlorobutane.
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Solution
When 2-chlorobutane is boiled with an alcoholic solution of potassium hydroxide, it undergoes the elimination of the hydrogen atoms from β-carbon and chlorine atoms from α-carbon resulting in the formation of But-2-ene and But-1-ene.
Reaction:
But according to Saytzeff's rule, in dehydrohalogenation reaction, the preferred product is that alkene which has a greater number of alkyl groups attached to doubly bonded carbon atoms.
Hence, But-2-ene is obtained as the major product in the dehydrohalogenation reaction of 2-chlorobutane.
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