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Consider the following two statements: Assertion (A): A compound containing a carbonyl group (C=O) adjacent to a heteroatom or ring can be subjected to Wolff-Kishner reduction to convert the C=O group into CH2, giving the corresponding alkane. Reason (R): Wolff-Kishner reduction converts a carbonyl group (>C=O) into a methylene group (>CH2). Choose the correct option:

1. Both A and R are true, but R is NOT the correct explanation of A.
2. A is true but R is false.
3. A is false but R is true.
4. Both A and R are true and R is the correct explanation of A.

Correct answer: Both A and R are true and R is the correct explanation of A.

Solution

Wolff-Kishner reduction converts a ketone or aldehyde (>C=O) into the corresponding methylene (>CH2) using NH2NH2/KOH at high temperature. Assertion A describes such a reduction yielding an alkane from a carbonyl compound — this is correct. Reason R correctly states the mechanism: >C=O -> >CH2. Moreover, R directly explains A. Therefore both are true and R is the correct explanation of A.

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