Match the neighbouring group in List I with the cyclic intermediate in List II. List I: P the carboxylate group of 2-bromopropanoate; Q the sulfide sulfur of CH3S-CH2CH2-Cl; R the tertiary nitrogen of (CH3)2N-CH2CH2-Cl; S the benzene ring of C6H5-CH2CH2-OTs. List II: 1 aziridinium ion; 2 phenonium ion; 3 alpha-lactone; 4 episulfonium ion.

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JEE Main levelSingle correct optionDifficulty 2 of 3o3140

Match the neighbouring group in List I with the cyclic intermediate in List II. List I: P the carboxylate group of 2-bromopropanoate; Q the sulfide sulfur of $CH X_{3} S - CH X_{2} CH X_{2} - Cl$ ; R the tertiary nitrogen of $(CH X_{3}) X_{2} N - CH X_{2} CH X_{2} - Cl$ ; S the benzene ring of $C X_{6} H X_{5} - CH X_{2} CH X_{2} - OTs$ . List II: 1 aziridinium ion; 2 phenonium ion; 3 alpha-lactone; 4 episulfonium ion.

AP-3, Q-1, R-4, S-2
BP-4, Q-3, R-1, S-2
CP-2, Q-4, R-1, S-3
DP-3, Q-4, R-1, S-2

Answer: D

Carboxylate oxygen gives a three-membered alpha-lactone; sulfur gives an episulfonium ion; nitrogen gives an aziridinium ion; the pi system of a phenyl ring gives a bridged phenonium ion (a spiro cyclohexadienyl cation).

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Answer: D

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