MCQ
The mechanism of $S _{ N } 1$ reaction is given as

$R - X \rightarrow R ^{\oplus} X ^{\ominus} \rightarrow R ^{\oplus} \| X ^{\ominus} \stackrel{ Y^\ominus }{\rightarrow} R - Y + X ^{\ominus}$

                     Ion pair       Solvent separated ion pair

A student writes general characteristics based on the given mechanism as:

$(a)$ The reaction is favoured by weak nucleophiles

$(b)$ $R^ \oplus$ would be easily formed if the substituents are bulky

$(c)$ The reaction is accompained by recemization

$(d)$ The reaction is favoured by non-polar solvents.

Which observations are correct $?$

  • A
    $b$ and $d$
  • $a, b$ and $c$
  • C
    $a$ and $c$
  • D
    $a$ and $b$

Answer

Correct option: B.
$a, b$ and $c$
b
$S _{ N }{ }^{1}$ favours

$(a)$ The reaction is favoured by weak nucleophiles

$(b)$ $R^ \oplus$ would be easily formed if the substituents are bulky

$(c)$ The reaction is accompained by recemization

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