91Ó°ÊÓ

Step1: Malonic ester synthesis

It’s a method in which a substituted derivative of acetic acid is formation occur in the presence of sodium ethoxide from dimethyl malonate followed by alkylation or acylation then hydrolysis followed by decarboxylation to form a derivate of acetic acid as a product.

Ethoxide is used as a base to form an enolate ion which in further reaction with the alkyl halide the alkylation occur means the by removal of the halide ion the alkyl group attached at the alpha position to the carbonyl.

It is the reaction which lead to the removal of the carbonyl group and releases carbon di-oxide$\left({\mathrm{CO}}_2\right)$ . Decarboxylation occurs by providing heat in the reaction.

As per the formation of the desired product the alkylation occur twice followed by the sodium ethoxide then decarboxylation occur to form desired product.

1. Acidic hydrogen protonated
2. Formation of enolate ion
3. Alkylation
4. Formation of again enolate ion
5. Alkylation again
6. Decarboxylation
7. Derivative of acetic acid formed

Mechanism