Question

How will you convert:
(i) Propanoic acid into Ethanamine
(ii) Ethanamine into Propanoic acid.

Answer 1

(i) Reaction between Propanoic acid and Ammonia to form Amide

CH3CH2COOH ——NH3——-> CH3CH2CONH2

Reaction with Br2/KOH followed by Hofmann Bromide reaction or Hofmann Rearrangement, primary amide is formed.

CH3CH2CONH2 ——Br2/KOH——-> CH3CH2NH2

(ii) For Ethanamine to Propanoic acid, first convert Ethanamine to Ethanoic acid

CH3CH2NH2 ——NaNO2/HCl——-> CH3CH2N2Cl —H2O—->CH3CH2OH—KMnO4/H+—->CH3COOH

Now convert Ethanoic Acid to Propanoic Acid

CH3COOH——LiAlH4/ether/H+——->CH3CH2OH——PCl5——->CH3CH2Cl——Ethanolic NaCN——->CH3CH2CN——NaNO2/HCl——H+-> CH3CH2COOH