Question

Match Column-I with Column-II

	Column-I (Reaction)		Column-II (Reagents)
A		P	Conc. KOH, $\Delta$
B		Q	CHCl$_3$, NaOH/H$_3$O$^+$
C		R	Br$_2$, NaOH
D		S	Zn-Hg/HCl

Choose the correct answer from the options given below:

	A	B	C	D
(1)	Q	S	P	R
(2)	R	S	Q	P
(3)	Q	P	R	S
(4)	R	S	P	Q

• A. Q S P R
• B. R S Q P
• C. Q P R S
• D. R S P Q

Answer 1

Answer: (D)

The correct match is A-R, B-S, C-P, D-Q. This corresponds to option (4).

Answer 2

The solution involves identifying each organic reaction given in Column-I and matching it with the appropriate reagents from Column-II.

A. Benzamide to Aniline:

This reaction involves the degradation of an amide to a primary amine with one carbon atom less. This is a characteristic reaction called Hofmann Bromamide Degradation. The reagents required for this reaction are Br₂, NaOH. Therefore, A matches with R.

B. Cyclopentanone-2-carbaldehyde to Cyclopentane:

This reaction involves the complete reduction of both a ketone group and an aldehyde group to alkane (methylene) groups. This type of reduction is achieved by Clemmensen reduction or Wolff-Kishner reduction. The reagents for Clemmensen reduction are Zn-Hg/HCl. Therefore, B matches with S.

C. Benzaldehyde to Potassium benzoate and Benzyl alcohol:

Benzaldehyde does not have an alpha-hydrogen atom. In the presence of a concentrated strong base, aldehydes without alpha-hydrogens undergo disproportionation, where one molecule is oxidized to a carboxylic acid salt and another molecule is reduced to an alcohol. This reaction is known as the Cannizzaro reaction. The reagents required are Conc. KOH, Δ. Therefore, C matches with P.

D. Phenol to Salicylaldehyde:

This reaction is the ortho-formylation of phenol, resulting in the formation of salicylaldehyde. This is a named reaction known as the Reimer-Tiemann reaction. The reagents required are CHCl₃, NaOH, followed by H₃O⁺. Therefore, D matches with Q.

Summary of Matches:

• A → R
• B → S
• C → P
• D → Q

Comparing these matches with the given options, the correct option is (4).