NEETChemistryHydrocarbons
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): Reaction of 2 -bromobutane with alcoholic KOH yields but- 2 -ene as the major product. Reason (R): In -elimination reactions, the preferred product is that alkene which has the greater number of alkyl groups attached to the doubly bonded carbon atoms. In the light of the above statements, choose th
Options
- ABoth (A) and (R) are correct but (R) is not the correct explanation of (A)
- BBoth (A) and (R) are correct and (R) is the correct explanation of (A)
- C(A) is correct but (R) is not correct
- D(A) is not correct but (R) is correct
Correct answer
B. Both (A) and (R) are correct and (R) is the correct explanation of (A)
Step-by-step solution
Assertion (A) is correct: When 2 -bromobutane is heated with alcoholic KOH , dehydrohalogenation occurs. It can form but- 1 -ene and but- 2 -ene. But- 2 -ene is the major product. Reason (R) is correct: Zaitsev's rule states that in dehydrohalogenation reactions, the preferred product is that alkene which has the greater number of alkyl groups attached to the doubly bonded carbon atoms. Since but- 2 -ene is a disubstituted alkene and but- 1 -ene is a monosubstituted alkene, Zaitsev's rule explains why but- 2 -ene i