Which of the following cannot be identified by carbyl amine test? 1\. \(\mathrm{C}_{3} \mathrm{H}_{7} \mathrm{NH}_{2}\) 2\. \(\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{NH}_{2}\) 3\. \(\mathrm{C}_{6} \mathrm{H}_{5}-\mathrm{NH}-\mathrm{C}_{6} \mathrm{H}_{5}\) 4. \(\left(\mathrm{C}_{3} \mathrm{H}_{7}\right)_{3} \mathrm{~N}\) (a) 2,3 (b) \(1,2,4\) (c) 3,4 (d) \(1,3,4\)

The detection of primary amines in organic compounds is essential for chemists in various fields, from pharmaceuticals to material science. One popular method for this is the Carbyl Amine Test. In simple terms, this test is based on the chemical reactivity of primary amines, which contain the structural unit R-NH₂. When a primary amine is treated with chloroform (CHCl₃) and an alcoholic solution of potassium hydroxide (KOH), a reaction occurs producing a foul-smelling compound known as an isocyanide or carbyl amine.

This distinct odor serves as a qualitative indication that a primary amine is present. However, it is crucial to remember that the test does not give a positive result for secondary or tertiary amines, or amides, as their structure differs from that of primary amines, preventing them from undergoing the same chemical transformation. Recognizing the structure of the amine is the key to understanding whether the Carbyl Amine Test will be successful.

Identification of chemical reactions is a fundamental skill in organic chemistry. It involves understanding how different functional groups behave under certain conditions. In the context of the Carbyl Amine Test, the reaction in question is a nucleophilic substitution where the primary amine acts as a nucleophile and displaces chloride in chloroform. This reaction is facilitated by the basic environment provided by potassium hydroxide.

The product of this reaction, an isocyanide, is identified by its strong odor. It's essential to have a firm grasp on reaction mechanisms and to be able to predict the outcome of reactions based on the starting materials. This allows chemists to choose appropriate tests, like the Carbyl Amine Test for primary amines, and to interpret the results accurately.

Organic compounds analysis encompasses a range of techniques to determine the composition and structure of organic molecules. When faced with a mixture of compounds, such as amines of different classes, chemical tests like the Carbyl Amine Test can be extremely valuable. They allow chemists to deduce structural information from simple qualitative observations.

In the given exercise, understanding the test's specificity for primary amines allows one to categorize compounds without employing sophisticated instrumentation. The key to effective analysis lies in recognizing functional groups and predicting their reactivity, as well as knowing the limitations of each test. For instance, while the Carbyl Amine Test is excellent for detecting primary amines, it would not be useful for compounds such as amides or tertiary amines, which require different analytical approaches.