NEET 2021 · ChemistryPrevious Year Question
The major product formed in the dehydrohalogenation of 2-bromopentane is pent-2-ene. This product formation is based on:
Answer: (C) (C) Saytzeff's Rule. In -elimination (dehydrohalogenation) of with alc.
- A.(A) Hofmann Rule
- B.(B) Huckel's Rule
- C.(C) Saytzeff's Rule✓
- D.(D) Hund's Rule
Correct Answer
(C) (C) Saytzeff's Rule
Solution & Explanation
In -elimination (dehydrohalogenation) of with alc. KOH, two alkenes are possible: pent-1-ene (less substituted) and pent-2-ene (more substituted). Saytzeff's rule states that the major product is the more substituted, more stable alkene, i.e. . Hofmann's rule (less substituted alkene) applies only with bulky bases.
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