Question

How will you convert:
(i) Benzene into Aniline
(ii) Aniline into Benzene.

Answer 1

Take your benzene. Add 1.HNO3 and H2SO4. This will put a nitro group onbenzene through electrophilic aromatic substitution, giving you nitrobenzene. Next, you can reduce this by using H2(g)/Pd over C, or Zn metal with HCl, this will give you aniline.

Treat aniline with nitrous acid which changes NH2 group to N2+Cl to form diazonium salt
C6H5NH2 + HNO2 ------------> C6H5N2+Cl
2.Now treat this diazonium salt with hypophosphorous acid(H3PO2),this will remove the diazonium group and replaces it with hydrogen to generate benzene.
C6H5N2+Cl + H3PO2 -------------> C6H6