UPSC Combined Geo-Scientist, Mains · 2016 · Mains Paper III
Q9(b). Robinson annulation
Question
Give the product and mechanism for cyclohexanone plus methyl vinyl ketone under basic conditions.
Answer in brief
A fused bicyclic alpha,beta-unsaturated ketone forms by Michael addition followed by intramolecular aldol condensation.
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CoversRobinson annulationCarbon–carbon bond formation
All parts of Question 9
- 9(a) Meerwein–Ponndorf–Verley reduction5 marks
- 9(b) Robinson annulation5 marks
- 9(c) Stereochemistry of Hofmann rearrangement5 marks