BITSAT2019ChemistryHaloalkanes and HaloarenesActual
Identify compound C in the following reaction C 7 H 8 → 3 Cl 2 / Δ A → Br 2 / Fe B → Zn / HCl C
Options
- Ao -bromotoluene
- Bm -bromotoluene
- Cp -bromotoluene
- D3 -bromo, 2 ,   4 ,   6 trichlorotoluene
Correct answer
B. m -bromotoluene
Step-by-step solution
Side chain hydrogen atoms are substituted by halogens in presence of light or heat by free radical mechanism. Ring hydrogens are substituted in presence of Lewis acid by electrofile. Alkyl halide (R-X) are reduced by Zn/HCl into alkane. The degree of unsaturation for compound C 7 H 8 is three 3 , as it reacts with Cl 2 / Δ . Hence C 7 H 8 is toluene, i.e C 6 H 5 . CH 3 . The whole reaction occurs as follows: