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Question 1 of 10
What are the two starting materials for a Robinson Annulation?
Correct answer: B. The two starting materials are an α-enolisable ketone (Michael donor) and methyl vinyl ketone, MVK (Michael acceptor, but-3-en-2-one).
Question 2 of 10
What role does methyl vinyl ketone (MVK) play in Robinson Annulation?
Correct answer: B. MVK is the Michael acceptor. Its β-carbon is electrophilic due to conjugation with the carbonyl. The donor enolate attacks this β-carbon in a 1,4-addition.
Question 3 of 10
What is the final product of a Robinson Annulation?
Correct answer: C. The product is a cyclohex-2-enone, a six-membered ring containing a conjugated α,β-unsaturated ketone, formed after aldol condensation and dehydration.
Question 4 of 10
Who discovered the Robinson Annulation?
Correct answer: C. Sir Robert Robinson published the reaction in 1935. He received the 1947 Nobel Prize in Chemistry for his work on alkaloids and natural products.
Question 5 of 10
How many key mechanistic steps does the Robinson Annulation involve?
Correct answer: C. 4 steps: (1) enolate formation, (2) Michael addition, (3) intramolecular aldol addition, (4) dehydration to cyclohex-2-enone.
Question 6 of 10
MVK stands for:
Correct answer: B. MVK = methyl vinyl ketone, IUPAC name but-3-en-2-one, formula CH₂=CH–CO–CH₃. It is the canonical Michael acceptor for Robinson Annulation.
Question 7 of 10
What base is commonly used in a simple Robinson Annulation?
Correct answer: A. Mild bases such as KOH or NaOEt in ethanol are used for simple substrates. LDA is used when regioselective enolate formation is required.
Question 8 of 10
What intermediate is formed after the Michael addition step in Robinson Annulation?
Correct answer: B. After Michael addition, a 1,5-diketone is formed. The two carbonyl groups are exactly five carbons apart, which is the ideal geometry for intramolecular aldol ring closure to a six-membered ring.
Question 9 of 10
Robinson Annulation is a combination of which two reactions?
Correct answer: C. Robinson Annulation is a tandem reaction: Michael addition (1,4-conjugate addition) followed by intramolecular aldol condensation (ring closure + dehydration).
Question 10 of 10
Which donor ketone is used to make the Wieland–Miescher ketone?
Correct answer: C. 2-Methyl-1,3-cyclohexanedione reacts with MVK in a Robinson Annulation to give the Wieland–Miescher ketone, a key building block in steroid and terpenoid total synthesis.