4. Michael addition reaction
• It is the conjugate addition reaction between an ἀ, ẞ- unsaturated carbonyl
compound and a compound with an active methylene group in the presence of
base (ex: NaOEt or secondary amine pyridine).
• Reaction:
5. The michael reaction nucleophile is called michael acceptor.
Ex:
The michael reaction electrophile is called michael acceptor.
Ex:
7. • Strong bases are poor Michael donars.
Ex- EtMgBr, LiAlH4,Organolithium etc.
• Weak bases are good Michael donars.
Ex- NaOEt
* kinetic product, less stable,
reversible, loses the stronger C=O
ℼ-bond.
* Thermodynamic product, more
stable, irreversible, loses the C=C
ℼ-bond, forms stable enolate.
10. Gilman reagent would alkylate the beta-position giving a carbonyl which
selectively alkylate on the target position. Here none of the sides is less substituted
to make the use of LDA or NaH beneficial for a regioselective alkylation. So, add on
alkyl halide before acid work up. In this case, the intermediate enolate is still
reactive and alkylation occurs on the side where the organocuprate had reacted.
11. • Dimedone is a cyclic ketone used in organic chemistry to determine
whether a compounds contains an aldehyde group.
• They are used as catalysts in the formation of transition metal-
complexes.
• This Reaction is performed in three steps that involve classical carbonyl
reactions, such as the Michael addition and Claisen condensation.
12. Conclusion
• The michael reaction is a useful method forming C-C bonds.
• Use of Michael addition followed by aldol condensation is an important route for
the synthesis of bicylic ketone and is known as Robinson annulation.
• Michael addition reaction has been a very classical reaction in the field of organic
synthesis, that is all kind of natural products and drugs.
13. Reference:
1. Organic chemistry - Jonathan clayden, Nick greeves and stuart warren
2. Organic reaction mechanisms -V.K. Ahluwalia
- Rakesh kumar Parashar