The Carbylamine reaction (also known as the Hoffman isocyanide test) is a specific chemical test used to detect the presence of primary amines. When a primary amine is heated with chloroform ($\mathrm{CHCl}_3$) and alcoholic potassium hydroxide (KOH), it produces an isocyanide (carbylamine), which is easily identified by its extremely foul, characteristic odor.$\mathrm{R-NH}_2 + \mathrm{CHCl}_3 + 3\mathrm{KOH} \xrightarrow{\Delta} \mathrm{R-NC} + 3\mathrm{KCl} + 3\mathrm{H}_2\mathrm{O}$Therefore, the major product is Isocyanide.