Read the passage carefully and answer the questions.
Alcohols and phenols are formed when a hydrogen atom in a hydrocarbon, aliphatic and aromatic respectively is replaced by - OH group. These are further classified on the basis of number of hydroxy groups and according to the hybridization of the carbon atom \( sp^2 \) or \( sp^3 \) to which the -OH group is attached. They find applications in industry as well as in day-to-day life. One of the most commercially obtained alcohol also known as wood spirit is obtained by destructive distillation of wood. Both alcohols and phenols are acidic in nature. The acidity of alcohols and phenols vary according to the nature of substituent(s) attached to them. Alcohols and phenols react with carboxylic acids, acid chlorides and acid anhydrides to form esters. Introduction of acetyl group in alcohols and phenols is called acetylation. Phenol undergo electrophilic aromatic substitution reaction because the -OH activates the benzene ring. It undergoes nitration, halogenation and sulphonation reactions.
The final product of the following reaction is:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Aspirin
Salicylic acid (2-hydroxybenzoic acid) has a phenolic –OH group. Acetic anhydride acetylates it (puts a \( \ce{CH3CO} \) group on the –OH oxygen), giving acetylsalicylic acid (2-acetoxybenzoic acid) and acetic acid:
\( \displaystyle \ce{HOC6H4COOH + (CH3CO)2O} \xrightarrow{\ce{H+}} \ce{CH3COOC6H4COOH + CH3COOH} \)
Acetylsalicylic acid is aspirin, a drug with analgesic, anti-inflammatory and antipyretic properties.
Why the other options are incorrect
Option (1) Paracetamol — Incorrect. Paracetamol is N-(4-hydroxyphenyl)acetamide; it is made by acetylating the –\( \ce{NH2} \) group of p-aminophenol, not from salicylic acid.
Option (2) Ibuprofen — Incorrect. Ibuprofen is 2-(4-isobutylphenyl)propanoic acid; it has no acetyl ester group and is not made by acetylation.
Option (4) Salicylaldehyde — Incorrect. Salicylaldehyde (2-hydroxybenzaldehyde) is made from phenol by the Reimer-Tiemann reaction with chloroform and sodium hydroxide; acetylation does not turn –COOH into –CHO.
NCERT (2026-27 edition):
Esterification
