Question

Primary amines react with benzoyl chloride to give:
(A) Benzamides
(B) Ethanamides
(C) Imides
(D) Imines

Answer 1

Hint: To answer this question, you must recall the reactions that take place in certain organic compounds when reacted with specific reagents. The reaction of a primary amine with a benzoyl chloride is a named reaction and is known as the Schotten- Baumann Reaction. The reaction is named after the German scientists Carl Schotten and Eugen Baumann as a sign of respect and consideration for their discovery. The reaction was described by them first in the year 1883. It results in formation of an aryl amide.

Complete step by step solution
The Schotten Bauman reaction is a condensation reaction which involves the reaction of a benzyl halide with a primary amine or that of an aliphatic acid halide with an amine in presence of a base. A water molecule is lost in the reaction and the product obtained in both the cases is an amide.
When primary amines react with benzoyl chloride, benzoylation occurs and benzamides are formed.
 $RN{H}_2+C_6{H}_{5}OCl\to C_6{H}_{5}CON{H}_2$
The correct answer is A.

Note
The mechanism of the Schotten- Bauman reaction is given as:
The first step of the reaction involves the attack of the nitrogen atom on the carbonyl carbon atom of the benzoyl chloride. Nitrogen in a primary amine carries a lone pair of electrons and the carbonyl carbon is highly electrophilic. As a result, a carbon- nitrogen bond is formed and the chloride ion is lost. Next, the nitrogen atom combines with the hydroxyl ions of the base present in the reaction mixture and loses a hydrogen ion. Nitrogen being more electronegative attracts the bond pair and an amide is formed as a result.