Question

Select the incorrect statement(s) from the following.

• A. Rate of sulphonation for $C_6{H}_6$ is higher than $C_6{D}_6$
• B. On treatment of salicylic acid with $B{r}_2/H_{2}O$ (in excess), it results in a dibromo product
• C. When $HCOOEt$ is treated with $MeMgBr$ in excess followed by hydrolysis, it will result in the formation of tertiary alcohol
• D.
  Products formed is a pair of enantiomer

Answer 1

Answer: (B), (C), (D)

Products formed is a pair of enantiomer
(a) The bond strength order is: $C-H<C-D<C-T$
During sulphonation electrophile react the benzene ring to form a sigma complex. To regain aromaticity, hydrogen atom is eliminated. Since $C-H$ bond is weaker than $C-D$ bond. Hence rate of sulphonation for $C_6{H}_6$ is relatively faster than $C_6{D}_6$.

(b) Salicylic acid gives 2,4,6-tribromophenol on treatment with $B{r}_2/H_{2}O$.

(c) When $HCOOEt$ is treated with excess of $MeMgBr$ followed by hydrolysis, it will result in the formation of secondary alcohol.

(d) $S_{N}2$ reaction proceeds through inversion of configuration. Since only isomers is taken so it will give a single product.