Chapter 7, Problem 63P

Interpretation Introduction

(a)

Interpretation: The given compounds A, B and C are to be arranged in order of increasing ${\text{S}}_{\text{N}}\text{2}$ reactivity.

Concept introduction: An alkyl halide is classified as $1°$, $2°$ or $3°$ when a halogen atom is bonded to primary, secondary or tertiary carbon atom of a hydrocarbon chain, respectively. A primary, secondary and tertiary carbon atom is bonded to one, two and three other carbon atoms, respectively. The order of increasing reactivity of alkyl halide towards ${\text{S}}_{\text{N}}\text{2}$ reaction is $\text{vinyl}<3°<2°<1°$.

Interpretation Introduction

(b)

Interpretation: The given compounds A, B and C are to be arranged in order of increasing ${\text{S}}_{\text{N}}\text{1}$ reactivity.

Concept introduction: In ${\text{S}}_{\text{N}}\text{1}$ reaction mechanism, the removal of halide from alkyl halide leads to the formation of carbocation. The order of increasing stability of carbocation is $\text{vinyl}<1°<2°<3°$.