Chapter 13, Problem 38P

Interpretation Introduction

Interpretation:

The structure of trifluralin and compound A in its given preparation reaction is to be identified.

Concept introduction:

Aryl halides (halogens attached to the $\text{benzene}$ ring) undergo nucleophilic aromatic substitution reaction only if there are strong deactivating groups present either ortho and para to the halogen in the ring.

Nitration of the substituted benzene follows electrophilic substitution reaction mechanism.

Nitro group ($-{\text{NO}}_2$) is a strong deactivating group, and it helps in the nucleophilic substitution of the halogens from the $\text{benzene}$ ring.

In the presence of sulfuric acid, concentrated nitric acid acts as a nitrating agent to the benzene ring.