The synthesis of phenylalanine from benzyl chloride and ammonia can be achieved through a three-step process involving the formation of an intermediate compound, benzylamine. Here is the step-by-step mechanism:Step 1: Formation of Benzylamine1. Benzyl chloride C6H5CH2Cl reacts with ammonia NH3 in a nucleophilic substitution reaction.2. The nitrogen atom in ammonia acts as a nucleophile and attacks the electrophilic carbon atom in benzyl chloride, which is connected to the chlorine atom.3. The chlorine atom leaves as a chloride ion Cl- , and the nitrogen atom forms a bond with the carbon atom, resulting in the formation of benzylamine C6H5CH2NH2 and a chloride ion Cl- .Step 2: Formation of Phenylacetonitrile1. Benzylamine C6H5CH2NH2 reacts with cyanogen bromide BrCN in a nucleophilic substitution reaction.2. The nitrogen atom in benzylamine acts as a nucleophile and attacks the electrophilic carbon atom in cyanogen bromide, which is connected to the bromine atom.3. The bromine atom leaves as a bromide ion Br- , and the nitrogen atom forms a bond with the carbon atom, resulting in the formation of phenylacetonitrile C6H5CH2CN and a bromide ion Br- .Step 3: Hydrolysis of Phenylacetonitrile to Phenylalanine1. Phenylacetonitrile C6H5CH2CN undergoes hydrolysis in the presence of a strong acid e.g., HCl and water H2O .2. The nitrile group CN is hydrolyzed to a carboxylic acid group COOH by the addition of water and a proton from the acid.3. The resulting compound is phenylalanine C6H5CH2CH NH2 COOH .In summary, the synthesis of phenylalanine from benzyl chloride and ammonia involves the formation of benzylamine, followed by the reaction with cyanogen bromide to form phenylacetonitrile, and finally, hydrolysis of phenylacetonitrile to obtain phenylalanine.