Example 9.1

Example . Write chemical equations for the following reactions: (i) Reaction of ethanolic NH with C H Cl. (ii) Ammonolysis of benzyl chloride and reaction of amine so formed with two moles of CH Cl. . Gabriel phthalimide synthesis Gabriel synthesis is used for the preparation of primary amines. Phthalimide on treatment with ethanolic potassium hydroxide forms potassium salt of phthalimide which on heating with alkyl halide followed by alkaline hydrolysis produces the corresponding primary amine. Aromatic primary amines cannot be prepared by this method because aryl halides do not undergo nucleophilic substitution with the anion formed by phthalimide. . Hoffmann bromamide degradation reaction Hoffmann developed a method for preparation of primary amines by treating an amide with bromine in an aqueous or ethanolic solution of sodium hydroxide. In this degradation reaction, migration of an alkyl or aryl group takes place from carbonyl carbon of the amide to the nitrogen atom. The amine so formed contains one carbon less than that present in the amide. Write chemical equations for the following conversions: (i) CH –CH –Cl into CH –CH –CH –NH (ii) C H –CH –Cl into C H –CH –CH –NH