- 2019: The correct answer is (C).
The reaction is:
R-NH2 + CHCl3 + 3KOH → R-NC + 3KCl + 3H2O
This reaction is known as the Hofmann reaction. It is a method for converting an amine to an isocyanide. The reaction is carried out by heating the amine with chloroform and potassium hydroxide. The chloroform is converted to the highly reactive dichlorocarbene, which reacts with the amine to form the isocyanide.
- 2020: The correct answer is (B).
The reaction is:
R-NH2 + NaNO2 + HCl → R-N2 + NaCl + 2H2O
This reaction is known as the Sandmeyer reaction. It is a method for converting an amine to an azo compound. The reaction is carried out by treating the amine with sodium nitrite and hydrochloric acid. The sodium nitrite is converted to nitrous acid, which reacts with the amine to form the diazonium ion. The diazonium ion is then treated with hydrochloric acid to form the azo compound.
