Fundamentals of Organic ChemistryChemistryGeneral Organic Chemistry
What is the correct order of relative yields for the following products obtained in the electrophilic aromatic nitration of tert -butylbenzene? (i) (ii) (iii)
Options
- A(ii) > (iii) > (i)
- B(iii) > (i) > (ii)
- C(i) > (ii) > (iii)
- D(i) > (iii) > (ii)
Correct answer
B. (iii) > (i) > (ii)
Step-by-step solution
The -C(CH ₃ ) ₃ (tert-butyl) group is an electron-donating group due to its +I effect, making it an ortho/para-directing group for electrophilic aromatic substitution. Due to the large, bulky nature of the tert-butyl group, there is significant steric hindrance at the ortho positions. As a result, the incoming electrophile ( NO ₂^+ ) preferentially attacks the less sterically hindered para position, making the para-isomer the major product. Although the ortho position is sterically hindered, it is still electronica