On heating benzyl amine with chloroform and ethanolic \(\mathrm{KOH}\), the product obtained is: (a) Benzyl alcohol (b) Benzaldehyde (c) Benzonitrile (d) Benzyl isocyanide

The identification of primary amines in an organic compound is a staple in organic chemistry laboratories, with the Carbylamine test offering a definitive reaction to confirm their presence.

Primary amines react uniquely with chloroform and an alcoholic base, producing a distinctive and foul-smelling isocyanide, also known as an isonitrile. This pungent odour makes the test easily discernible even without sophisticated equipment. However, it's worth noting that this test is specific only to primary amines; secondary and tertiary amines do not undergo this reaction and are thus not detected by this method.

Students often seek clarity on why this specificity occurs. The underlying mechanism involves the deprotonation of the amine to form an amide ion, which subsequently attacks the chloroform that has been activated by the base. This reaction culminates in the formation of an isocyanide group, confirming a primary amine's presence in the original sample.

Chemical reactions form the cornerstone of organic chemistry, transforming substrates into products through a variety of mechanisms. The Carbylamine reaction is emblematic of such transformations, illustrating how reaction conditions and the nature of reactants dictate the products formed.

In this context, understanding the reactivity of functional groups provides insight into the array of chemical processes possible within organic chemistry. For instance, in the Carbylamine reaction, the reactivity of the primary amino group is key to forming the isocyanide product.

Gaining familiarity with these types of reactions not only helps in identification tests but also equips students with knowledge applicable to synthesizing complex organic molecules. Furthermore, these reactions emphasize the importance of maintaining stringent conditions to ensure specificity and yield of the desired product.

Benzyl isocyanide, an organic compound with a distinctive odour, can be synthesized through the Carbylamine reaction, which involves a primary amine, chloroform, and an alcoholic base. The preparation process demands careful control of reactants and conditions to favor the intended product over possible side products.

In teaching students about this synthesis, it is critical to stress the proportions of reagents, the temperature control necessary during heating, and the rigorous exclusion of moisture to prevent hydrolysis. The method's elegance lies in its simplicity and the clear visual and olfactive indication of success—the creation of benzyl isocyanide's unique scent signals the reaction's progression.

When examining mechanisms, it's essential to deconstruct each step of the reaction for students to understand how the reactants interact on a molecular level, eventually leading to the creation of benzyl isocyanide. This comprehensive understanding is beneficial for students as they encounter more complex synthetic pathways in their studies.