Question

1. (3p) Draw the mechanism and the expected reaction product for the following reaction: xo 2. (3p) Draw the mechanism and the expected Nucleophilic Substitution Reaction Product for the following reaction: 3. (3p) What reagent is necessary in the hydrolysis of carboxylic acid derivatives? Rank these derivatives in order of their reactivity.

Answer 1

1. Here, nitrogen atom with a positive charge on it acts as the electrophile and in the 2nd compound, ortho and para position of NMe₂ group are electron rich due to delocalisation of lone pair of electrons on nitrogen with the benzene ring. The meta position is electron deficient.

As the para position is already occupied by a ethyl group, ortho position is the only electron rich site and it acts as nucleophile and attacks the electrophile to create a positive charge on meta position. Then the aromaticity of the ring is restored by hydrogen atom at the ortho position.

'N في مصر I RN NEN + N=NO H >N Z NEN-