Making kinetic and thermodynamic enolates via solvent-free high speed ball milling

Abstract

We investigated the ability to selectively form products arising from a kinetic or a thermodynamic enolate under solvent-free high speed ball milling conditions. Using 2-methylcyclohexanone as the substrate and sodium hydroxide or lithium hexamethyldisilazide as the base, we were able to trap the thermodynamic or kinetic enolate in high selectivity. Although all the reagents were ball milled simultaneously, we observed no products resulting from aldol condensation.