Baeyer-Villiger oxidations in ionic liquids. A facile conversion of ketones to esters and lactones

A variety of cyclic and acyclic ketones underwent readily oxidation with m-chloroperbenzoic acid (m-CPBA) in ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate [bmim]BF4 to afford esters/lactones with high selectivity, ease of product separation and in excellent chemical yields. The reaction proceeded smoothly in ionic liquid without the need of any additional acid or base catalyst. The ketones show enhanced reactivity in ionic liquids thereby reducing reaction times and improving the yields significantly.