The major product in the following reaction is CSA = camphorsulfonic acid · ABC26OR0440
Subject: Organic Chemistry · Chapter: Reagents, Reaction Mechanisms & Named Reactions · Topic: Named Reactions · Exam: CSIR NET DEC 2019 · Marks: 2 · Difficulty: Medium
The major product in the following reaction is 
CSA = camphorsulfonic acid
CSA = camphorsulfonic acid(a)
(b)
(c)
(d)
Answer
Answer: B ✓ checked by 4AB · confidence medium
Explanation
Formaldehyde and the secondary amine form an iminium (CSA); aza-Prins attack by the styrenic alkene, then a pinacol-type 1,2-shift of the ring bond onto the carbinol carbon expands the ring — the cis-fused cycloheptanone-pyrrolidine with the phenyl at the ring junction (b).
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