The conversion of Propyne to Benzene can be brought out in 4 steps. Choose the reagents to be used, in the proper sequential order, to bring out the conversion. Reagents provided: alc. KOH , H ₂ / Pd , Na / dry ether, HBr , HBr / ( C ₆ H ₅ CO )₂ O ₂ , Soda-lime, Cr ₂ O ₃ (high T and P), Conc. H ₂ SO ₄

Step-by-step solution

The conversion of propyne ( CH₃-C CH ) to benzene ( C₆H₆ ) involves the following steps: Partial hydrogenation of propyne to propene using H₂ / Pd (Lindlar catalyst or poisoned Pd). CH₃-C CH + H₂ Pd CH₃-CH=CH₂ Anti-Markovnikov addition of HBr to propene using peroxide ( HBr / (C₆H₅CO)₂O₂ ) to obtain 1-bromopropane. CH₃-CH=CH₂ + HBr peroxide CH₃-CH₂-CH₂Br Wurtz reaction using Na / dry ether to convert 1-bromopropane to n-hexane. 2 CH₃-CH₂-CH₂Br + 2 Na dry ether CH₃-CH₂-CH₂-CH₂-CH₂-CH₃ Aromatization of n-hexane to be