What is Hinsberg reagent?
Benzene sulphonyl chloride $\left(\mathrm{C}_6 \mathrm{H}_5 \mathrm{SO}_2 \mathrm{Cl}\right)$ is known as Hinsberg reagent. It is used to distinguish between primary, secondary and tertiary amine.
Why is benzene diazonium chloride not stored and is used immediately after its preparation?
Benzene diazonium chloride are highly unstable and stable for a very short time span in solution at low temperature. Due to its instability, it is used immediately after its preparation.
Why does acylation of $-\mathrm{NH}_2$ group of aniline reduces its activating effect?
Acylation of $-\mathrm{NH}_2$ group of aniline reduces its activity due to resonance of lone pair of nitrogen towards the carbonyl group hence $0-, p^{-}$directive influence of amino group get disturbed.
Explain why $\mathrm{MeNH}_2$ is stronger base than MeOH ?
Basicity of $\mathrm{MeNH}_2$ and MeOH can be explained on the basis of electronegativity of N and O atom. $\mathrm{MeNH}_2$ is stronger base than MeOH because of low electronegativity value of N , it is easy for nitrogen to loose its lone pair readily than compared to MeOH .
What is the role of pyridine in the acylation reaction of amines?
Pyridine being a base, is used to remove the side product i.e., HCl from reaction mixture.
