Compounds Containing Nitrogen

A hydrocarbon \(A\left(\mathrm{C}_4 \mathrm{H}_8\right)\) on reaction with \(\mathrm{HCl}\) gives a compound \(\mathrm{B}\left(\mathrm{C}_4 \mathrm{H}_9 \mathrm{Cl}\right)\) which on reaction with \(1 \mathrm{~mol}\) of \(\mathrm{NH}_3\) gives compound \(\mathrm{C}\left(\mathrm{C}_4 \mathrm{H}_{10} \mathrm{N}\right)\). On reacting with \(\mathrm{NaNO}_2\) and \(\mathrm{HCl}\) followed by treatment with water, compound \(C\) yields an optically active compound \(D\). The compound \(D\) is