Considering the reaction sequence given below, the correct statement(s) is(are)
← JEE Advanced 2022 · Paper 1![CH3CH2COOH → [1. Br2, red phosphorous; 2. H2O] → P → [1. potassium phthalimide; 2. NaOH; 3. H3O+] → Q + phthalic acid (benzene-1,2-dicarboxylic acid).](/figures/ja-2022-p1/ja-2022-p1-che-q13-f1.png)
ChemistryMultiple correct+4 / -2Question 49 of 54
JEE Advanced 2022 · Paper 1, Chemistry question 13
![CH3CH2COOH → [1. Br2, red phosphorous; 2. H2O] → P → [1. potassium phthalimide; 2. NaOH; 3. H3O+] → Q + phthalic acid (benzene-1,2-dicarboxylic acid).](/figures/ja-2022-p1/ja-2022-p1-che-q13-f1.png)
Answer and worked solution
Official answer: B, C, D
P. The Hell-Volhard-Zelinsky reaction gives 2-bromopropanoic acid, .
Q. The Gabriel synthesis (potassium phthalimide, then hydrolysis) gives alanine, , along with phthalic acid.
The options.
- (A) False: does not reduce carboxylic acids.
- (B) True: ammonia displaces bromide, giving alanine.
- (C) True: a primary aliphatic amine and give .
- (D) True: the -Br withdraws electrons, so P is more acidic than propanoic acid.