Amines Test - 8

Its molecular formula is C₄H₈O₂ and its chemical formula is CH₃COOC₂H₅.

Due to the presence of lone pair on nitrogen, methyl amine acts as a Lewis base and reacts with HCl, H+ ion from HCl forms an adduct (salt) methyl ammonium chloride, CH₃NH₃⁺Cl^-.

Direct nitration of aniline yield significant amount of meta derivative, this is because the use of HNO₃ during nitration of aniline causes the formation of anilinium ion(C₆H₅NH₃⁺). Anilinium ion is responsible for the formation of metra nitro aniline. To prevent this, initial reaction of aniline with acetic anhydride acetylates -NH₂ group.

C₆H₅NH₂ + CH₃COOCOCH₃ →  C₆H₅NHCOCH₃.

Now, -NHCOCH₃ is an activating group, which on nitration followed by hydrolysis form para nitro aniline as a major product.

AlCl₃ being a lewis acid reacts with the lone pair of -NH₂ group of aniline forming an adduct (C₆H₅NH₂⁺AlCl₃) which deactivates the benzene system hence no friedal craft reaction occurs.

Base hydrolysis of ester produces the salt of carboxylic acid and alcohols as the product, and soaps are salts of carboxylic acids. Therefore, this reaction is called as saponification reaction.

In Gabriel Pthalamide reaction, the sodium or potassium salt of pthalimide is N-alkylated with a primary alkyl halide to give the corresponding N-alkylphthalimideis for producing primary amines. This is because of the reaction of sodium or potassium salt of phthalimide with alkyl halide impure SN₂ reaction.

In Gabriel phthalimide reaction, a potassium salt of phthalimide is formed. It reacts readily with the primary alkyl halide to form the corresponding alkyl derivative. But aryl halide (C₆H₅X) does not react with potassium salt of phthalimide. Because C-X bond in haloarene (alkyl halide) is difficult to be cleaved due to a partial double bond character and hence, do not undergo SN₂ reaction with potassium salt of phthalimide. So, aromatic primary amines cannot be prepared by Gabriel phthalimide synthesis.