JEE MainChemistryAlcohols Phenols and Ethers
An organic compound 'A' with the molecular formula C ₇ H ₆ O ₂ reacts with hydroxylamine to form compound 'B'. Upon heating with P ₂ O ₅ , compound 'B' yields 2-hydroxybenzonitrile. Which of the following sets of reagents will produce compound 'A' as the major product when reacted with phenol?
Options
- ACO ₂ and aqueous NaOH under pressure, followed by acidification
- BCHCl ₃ and aqueous NaOH , followed by acidification
- CHCN , HCl and anhydrous AlCl ₃ , followed by hydrolysis
- DCH ₃ Cl and anhydrous AlCl ₃
Correct answer
B. CHCl ₃ and aqueous NaOH , followed by acidification
Step-by-step solution
Working backwards from the final product, heating an oxime with a dehydrating agent like P ₂ O ₅ yields a nitrile. Since the product is 2-hydroxybenzonitrile, compound 'B' must be 2-hydroxybenzaldehyde oxime. Compound 'B' is formed by the reaction of 'A' with hydroxylamine ( NH ₂ OH ). Thus, compound 'A' is 2-hydroxybenzaldehyde (also known as salicylaldehyde). The molecular formula of salicylaldehyde is C ₇ H ₆ O ₂ , which matches the given data. To synthesize salicylaldehyde as the major product starting from phe