Question
Explain ẞ Elimination reaction with example. ### Explain Dihydrohalogenation reaction of Haloalkane ### Explain zaitsev or Saytzeff rule with example.
✓
Answer
→ When a haloalkane with ẞ-hydrogen atom is heated with alcoholic solution of potassium hydroxide, there elimination of hydrogen atom from ẞcarbon and a halogen atom from the a-carbon atom.
→ As a result, an alkene is formed as a product. Since ẞ-hydrogen atom is involved in elimination, it is ofte called ẞ-elimination.
→ If there is possibility of formation of more than one alkene due to the availability of more than one ẞ-hy drogen atoms, usually one alkene is formed as the major product.
→ These form part of a pattern was first observed by Russian chemist, Alexander Zaitsev (also pronounced Saytzeff).
→ A rule which can be summarised as "in dehydrohalogenation reactions, the preferred product is that alken which has the greater number of alkyl groups attached to the doubly bonded carbon atoms."
→ Thus, 2-bromopentane gives pent-2-ene as the major product.
→ As a result, an alkene is formed as a product. Since ẞ-hydrogen atom is involved in elimination, it is ofte called ẞ-elimination.
→ If there is possibility of formation of more than one alkene due to the availability of more than one ẞ-hy drogen atoms, usually one alkene is formed as the major product.
→ These form part of a pattern was first observed by Russian chemist, Alexander Zaitsev (also pronounced Saytzeff).
→ A rule which can be summarised as "in dehydrohalogenation reactions, the preferred product is that alken which has the greater number of alkyl groups attached to the doubly bonded carbon atoms."
→ Thus, 2-bromopentane gives pent-2-ene as the major product.
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