Enolates act as nucleophiles through carbon, attacking a large number of electrophiles (haloalkanes, epoxides, carbonyls, esters...).

At this point we will focus on the reaction between enlolates and haloalkanes, which allows the addition of carbon chains to the a position of the chain. Cyclohexanone is converted to 2-Methylcyclohexanone by treatment with LDA followed by methyl iodide.


Stages of the mechanism by which cyclohexanone is alkylated:

Stage 1. Formation of the enolate

Stage 2. N type reaction )

Alkylation reactions have two major problems.
1. Competition with aldol condensation.
Carbonyls in a basic medium tend to condense to form aldols. 2. The reaction is difficult to control and tends to polyalkylate the carbonyl.