What two reactions are involved in Robinson annulation?
The Robinson Annulation is the name for a process that combines two key reactions you’ve learned previously into one longer sequence. The reaction begins with a Michael reaction, followed by an intramolecular aldol condensation to give a new six-membered ring containing an alpha, beta unsaturated ketone.
What is the product of Robinson annulation reaction?
The Robinson annulation is a chemical reaction used in organic chemistry for ring formation. It was discovered by Robert Robinson in 1935 as a method to create a six membered ring by forming three new carbon–carbon bonds….
| Robinson annulation | |
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| RSC ontology ID | RXNO:0000380 |
What is the difference between Michael addition and Robinson annulation?
The key difference between Michael addition and Robinson annulation is that Michael addition forms an aliphatic compound, whereas Robinson annulation forms a ring structure. Overall, Michael addition and Robinson annulation are organic synthesis reactions.
Can the Robinson annulation be done under acidic conditions?
Mechanism of the Robinson Annulation The first step in the process is the Michael Addition to an α,β-unsaturated ketone, such as methyl vinyl ketone (ethyl vinyl ketone is shown above): The Robinson Annulation can also proceed under acidic catalysis, with the entire process occurring in one pot, as shown below.
Which are the application of Robinson annulation?
The Robinson annulation is a chemical reaction used in organic chemistry for ring formation. It was discovered by Robert Robinson in 1935 as a method to create a six membered ring by forming three new carbon–carbon bonds.
Why is dehydration favored at the end of Robinson annulation?
Why is dehydration favored at the end of the reaction? Water is eliminated (dehydration) under basic conditions to form the enone. The proton is pretty acidic and the leaving group is bad meaning a e1 cb reaction necessary.
What is a Michael donor?
Michael reaction (Michael addition): The conjugate addition of a carbanion, enolate, enamine, or other carbon nucleophile to the β-carbon of an enone, enal, or other α, β-unsaturated compound. This results in a new carbon-carbon bond at the β-carbon. The Michael reaction nucleophile is called the Michael donor.
What are the two starting materials for a Robinson annulation?
The two starting materials for a Robinson annulation are an α,β-unsaturated carbonyl compound and an enolate. The Robinson annulation forms a six-membered ring and three new carbon-carbon bonds—two σ bonds and one π bond.
Why is dehydration favored at the end of the reaction?