Catalytic Oxidation with Hydrogen Peroxide in Ionic Liquids

Catalytic oxidation reactions in ionic liquids using H2O2 as oxidant are reviewed and transition metal catalysts as well as metal-free catalysts are considered. Different ionic liquids, catalyst systems and substrates are compared. The surveyed reactions comprise the oxidation of alcohols, aromatic aldehydes and ketones, oximes, alkanes, benzene and sulfur compounds, Baeyer-Villiger oxidation, epoxidation and dihydroxylation of alkenes as well as the oxidation of alkenes to ketones and carboxylic acids. Several advantages over conventional reaction media such as simple product separation techniques, recycling strategies that allow for multiple use of the catalyst systems, mild reaction conditions or the possibility to run reactions without any transition metal catalyst are evaluated.