Novel electrochemical systems for asymmetric oxidation
thesisposted on 21.06.2011, 14:24 by Claire Elliott
Organic reactions, which can be carried out in water and in the absence of heavy metals, are becoming more important today due to concerns over safety and environmental impact. Thus if an oxidation reaction can be carried out, where the oxidant is generated in-situ using electrolysis, then this is advantageous over existing systems that use strong or large volumes of stoichiometric oxidant and solvent, that cannot be recycled. In this thesis a wide variety of conditions and methods for producing enantiomerically enriched epoxides and sulfoxides have been reported using both electrochemically generated percarbonate and hypochlorite. It has been possible to carry out a range of oxidation reactions both as a one-pot reaction and with the oxidant generated in a batch process. Carrying out sulfoxidation reactions as a batch process with a carbonate solution it is possible to obtain ees of 20%. Using our in-situ generation of oxidant, as a one-pot electrochemical reaction, has provided a wide range of sulfoxides in good to excellent yield, with the application of this system to the oxidation of alkenes using a chiral iminium salt resulting in 100% conversion, with up to 44% ee.