Question

Which of the following compounds will given racemic mixture on nucleophilic substitution by $O{H}^{\ominus }$ ion?
(a) $C{H}_3-\underset{\stackrel{|}{C_2{H}_5}}{CH}-Br$
(b) $C{H}_3-\stackrel{\underset{|}{Br}}{\underset{\stackrel{|}{C_2{H}_5}}{C}}-C{H}_3$
(c) $C{H}_3-\underset{\stackrel{|}{C_2{H}_5}}{CH}-C{H}_{2}Br$

• A. $\left(a\right)$
• B. $\left(a\right),\left(b\right),\left(c\right)$
• C. $\left(b\right),\left(c\right)$
• D. $\left(a\right),\left(c\right)$

Answer 1

The correct option is A $\left(a\right)$

$C:$ $1^{\circ }$ Alkyl halide can directly forms substitution product without inversion.

$B:$ $3^{\circ }$ Alkyl halide allows $O{H}^{-}$ to attack only from one side d after leaving of halide $O{H}^{-}$ attacks due steric hinderance.

$A:$ $2^{\circ }$ Alkyl halide allows $O{H}^{-}$ to attack while leaving of $B{r}^{-}$ hence inversion of molecule occurs forms racemic mixture.