Q16 · CSIR NET Chemistry, December 2014
Paper: CSIR NET December 2014 · Subject: Organic Chemistry · Chapter: Reagents, Reaction Mechanisms & Named Reactions · Topic: Reagents, Reaction Mechanisms & Named Reactions – General · Marks: 2 · Difficulty: Medium
The products A and B in the following reaction sequence are: 
A $\xrightarrow[\mathrm{THF,\ EtOH}]{\mathrm{SmI_2}}$ B
A $\xrightarrow[\mathrm{THF,\ EtOH}]{\mathrm{SmI_2}}$ B(a)A = 
B = 
B = (b)A = 
B = 
B = (c)A = 
B = 
B = (d)A = 
B = 
B = Answer
Answer: A ✓ checked by 4AB · confidence high
Explanation
Co₂(CO)₈/NMO Pauson–Khand of the enyne gives the fused cyclopentenone with the TMS at the α-carbon (A); SmI₂ cleaves the N–O bond of the isoxazolidine, leaving the Boc-amine and the primary alcohol (B) — (a).
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