Q20 · CSIR-NET Chemistry, December 2016
Paper: CSIR-NET December 2016 · Subject: Organic Chemistry · Chapter: Reagents, Reaction Mechanisms & Named Reactions · Topic: Named Reactions · Marks: 2 · Difficulty: Medium
Under review — part of this question (a structure or an option) is not clear in the source scan. 4AB is checking it against the original book; the answer shown may change.
Products of the following reaction is: 
(a)
(b)
(c)
(d)
Answer
Under review — not yet confirmed.
Answer: C
Explanation
BF₃ activates the alcohol and the indole alkylates intramolecularly. Attack at C-3 gives a spiroindolenine that rearranges (1,2-shift) to C-2, so the label ends up at either carbon: the two tetrahydrocarbazoles of (c).
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