Consider the given molecule with four labeled C - Cl bonds (P, Q, R, and S). Which of these bonds will undergo heterolytic cleavage most readily to form a carbocation?

Step-by-step solution

The ease of heterolytic cleavage of a C - Cl bond depends on the stability of the carbocation formed after the departure of the chloride ion ( Cl ^- ). The more stable the carbocation, the more readily the bond will cleave. Let us analyze the carbocations formed by the cleavage of each labeled bond: 1. Bond P: Cleavage forms a tertiary benzylic carbocation. This carbocation is highly stabilized by resonance with the benzene ring and by hyperconjugation from the six -hydrogens of the two methyl groups. 2. Bond Q: Cl