Alkylation of Enolate Ions : Direct Alkylation

Both the malonic ester synthesis and acetoacetic ester synthesis can be preformed with relatively mild bases, such as sodium ethoxide, because of the unusually acidic nature of the dicarbonyl compounds. However, if a stronger base is used, such as LDA, monocarbonyl compounds can also be alkylated in the alpha position.

Mechanism

1) Enolate formation

2) S_N2 attack