MixedHardQuestion 820013
Question
The Sandmeyer reaction replaces the diazonium group (−N₂⁺) with:
- A−Cl, −Br, or −CN using CuCl/CuBr/CuCN as catalystCorrect
- B−OH only
- C−NO₂ only
- D−H only
Correct answer
−Cl, −Br, or −CN using CuCl/CuBr/CuCN as catalyst
Explanation
Sandmeyer reactions: ArN₂⁺ + CuCl → ArCl + N₂; + CuBr → ArBr; + CuCN → ArCN. The Cu(I) salt acts as catalyst in the radical mechanism. Also: + CuI → ArI (Finkelstein-type); + H₂O/H⁺ → ArOH (diazonium hydrolysis); + HBF₄ → ArF (Balz-Schiemann).