The Baylis-Hillman Reaction Mechanism

                The Baylis-Hillman Reaction

The Baylis-Hillman Reaction form carbon-carbon bond between an alkene and an electron accepting molecule using catalyst like tertiary amine or phosphine

We use in Baylis-Hillman Reaction DABCO

IUPAC-1,4-diazobicyclo[2,2,2]octane
it is less basic and more nucleophile
it is good leaving group
it act as catalyst

Step-1 of The Baylis-Hillman Reaction
DABCO attack the activated alkene. This forms temporary bond between the catalyst and the alkene generating a zwitter-ion (Zwitter-ion is a molecule with

 both positive and negative charge)

Step-2 of The Baylis-Hillman Reaction
The doubly bonded carbon of zwitter -ion approach the aldehyde and form new C-C bond

Step-3 of The Baylis-Hillman Reaction
Proton transfer(Is a fundamental step in many organic reactions and involves the movement of a proton (H⁺) from an acid to a base)

Step-4 of The Baylis-Hillman Reaction
leaving group is leave(DABCO) is leaving group

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