NEETChemistryHaloalkanes and Haloarenes
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): Reaction of but-1-ene with HBr in the presence of peroxide followed by reaction with KCN and subsequent reduction yields pentan-1-amine. Reason (R): The addition of HBr to but-1-ene in the presence of peroxide proceeds via the formation of a more stable primary free radical. In the light of the abo
Options
- ABoth (A) and (R) are true and (R) is the correct explanation of (A)
- BBoth (A) and (R) are true but (R) is not the correct explanation of (A)
- C(A) is true but (R) is false
- D(A) is false but (R) is true
Correct answer
C. (A) is true but (R) is false
Step-by-step solution
Assertion (A) is true: But-1-ene reacts with HBr in the presence of peroxide to undergo anti-Markovnikov addition, forming 1-bromobutane. Nucleophilic substitution of 1-bromobutane with KCN yields pentanenitrile. Reduction of pentanenitrile gives pentan-1-amine. Reason (R) is false: The peroxide effect proceeds via a free radical mechanism. The bromine free radical attacks the terminal carbon of but-1-ene to form a more stable secondary free radical intermediate, not a primary free radical. The formation of the sec