NEET
- Exam
- NEET
- Subject
- Chemistry
- Chapter
- Carboxylic Acid Derivatives
NEET · Chemistry · Carboxylic Acid Derivatives
Which of the following reactions yield carboxylic acids. (A)...
Which of the following reactions yield carboxylic acids.
(A) (\mathrm{RMgX}+\mathrm{CO}_2 \xrightarrow{\mathrm{H}_2 \mathrm{O}})
(B) (\mathrm{Ph}-\mathrm{OH}+\mathrm{NaOH}+\mathrm{CO}_2 \longrightarrow)
(C) (\mathrm{PhCN}+\mathrm{H}_3 \mathrm{O}^{\oplus} \longrightarrow)
(D) (\mathrm{PhOH}+\mathrm{CHCl}_3+\mathrm{KOH} \longrightarrow)
Options
- AA, B and C are correct
- BA & B are correct
- CB & D are correct
- DA & C are correct
Correct answer
A. A, B and C are correct
Step-by-step solution
(A) (\mathrm{RMgX}+\mathrm{CO}_2 \rightarrow) (on hydrolysis) (\rightarrow \mathrm{R}-\mathrm{COOH})
Yes, this is a standard reaction of Grignard reagent with (\mathrm{CO}_2), giving carboxylic acid.
(B) (\mathrm{Ph}-\mathrm{OH}+\mathrm{NaOH}+\mathrm{CO}_2 \rightarrow) Salicylic acid (Kolbe-Schmitt reaction)
Yes, this is the Kolbe reaction, which yields ortho-hydroxybenzoic acid (salicylic acid).
(C) (\mathrm{Ph}-\mathrm{C} \equiv \mathrm{N}+\mathrm{H}_3 \mathrm{O}^{+} \rightarrow \mathrm{Ph}-\mathrm{COOH})
Hydrolysis of nitriles in acidic medium gives carboxylic acids.
(D) (\mathrm{PhOH}+\mathrm{CHCl}_3+\mathrm{KOH} \rightarrow) Salicylaldehyde (Reimer-Tiemann reaction)
This gives salicylaldehyde (-CHO group), not a carboxylic acid.