Treatment of benzene with CO/HCl in the presence of anhydrous AIC1/CuCl followed by reaction with Ac0/NaOAc gives compound X as the major product. Compound X upon reaction with Br/NaCO3, followed by heating at 473 K with moist KOH furnishes Y as the major product. Reaction of X with H/Pd-C, followed by H3PO4 treatment gives Z as the major product. The compound Y is (A) (C) COBR (B) (D) OH HO Br Br Br O COBR