91Ó°ÊÓ

In this sodium ethoxide is used for condensation to avoid transesterification. Ethoxide is the base which protonates the acidic hydrogen to form $\mathbf{β}$keto ester.

Ethoxide is used as a base to form enolate ions which form $\mathrm{β}$keto ester on further reaction with the alkyl halide the alkylation occurs means the removal of halide ion in the alkyl group attached at the alpha position to the carbonyl.

1. Acidic hydrogen protonated
2. Formation of the enolate ion
3. Dieckmann’s reaction
4. Alkylation
5. Hydrolysis

Reaction Mechanism

1. Acidic hydrogen protonated
2. Formation of enolate ion
3. Alkylation
4. Formation of alkene by adding base to remove halogen
5. Hydrolysis

1. Acidic hydrogen protonated
2. Formation of the enolate ion
3. Robinson reaction followed by an aldol reaction
4. Formation of alkane by reducing alkene in presence of Lindlar’s catalyst

Substitution of phenyl ring

1. Acidic hydrogen protonated
2. Formation of enolate ion
3. Claisen condensation
4. Alkylation