JEE Main202623 January 2026Evening ShiftChemistryHydrocarbonsActual

Consider the following reaction of benzene. In compound (Q), the percentage of oxygen is _ _ _ _ %. (Nearest integer)

Correct answer

Step-by-step solution

Benzene reacts with CH ₃ -CO-CH ₂ -CH ₂ -CO-Cl in the presence of anhydrous AlCl ₃ (Friedel-Crafts acylation) to give product P (a keto-ketone). P on treatment with aq. NaOH and heating undergoes intramolecular aldol condensation to give a cyclic enone Q. Molecular mass of Q = 157 Percentage of oxygen in Q = 16 157 100 = 10.19 % 10 %

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