[Unco]

I am currently running a series of reactions by reacting cycloalkyl ketones derived enolates with another electrophile. The question is what are some conditions that would favor the nucleophilic attack from the carbon anion over the oxygen anion (conditions like solvent, base used to deprotonate the ketone, temperature, etc.)?

Thank you for answering.

[phth]

it depends on the stability of the ketone, and the electrophile..  For example, strong base plus tBuCl-->isoprene instead of alkylation..  Morpholine eanamines alkylate the kinetic side: why?  What factors could favor thermodynamic alkylation?

[pgk]

The specific conditions depend on the desired regioselectivity and the chemical structure of the cycloketone, e.g.  enamines that work by Sn2 mechanism, favor α,α’- dialkylation; contrary to silyl enol ethers that work by Sn1 mechanism and favor α,α – dialkylation or alkylation of the α secondary carbon. Using very strong bases α-alkylation can occur directly and thus, avoiding enamines or silyl enol ethers. In presence of β-carbonyl, β-carboxyl οr any other β-electron attractive group, α-alkylation can occur by using less strong bases. And so on…
The best method is the preliminary literature search for α-alkylation of cycloketones with similar chemical structure.

[Unco]

thanks for the answers