Electrocatalysis in Iodine-based Oxidations

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The direct use of electrical energy to induce chemical transformations is an efficient and green activation mode of organic molecules. It avoids expensive catalysts and ligands to enable chemical transformations which are otherwise difficult to achieve. Reagent waste is avoided since electrons induce the chemical reactions. Sustainable electricity is becoming increasingly available by exploiting sun and wind energy.Oxidations typically require stoichiometric amounts of a terminal oxidant and many important transformations in organic synthesis have been developed using this approach. Electrochemical recycling of the oxidant is possible in several cases. The key requirement for a successful reaction generating and using hypervalent iodine compounds in only catalytic amounts is the ability of the stoichiometric oxidant to selectively make the hypervalent iodine compound in the presence of the substrate. The stoichiometric oxidant has to be carefully selected as it must not react directly with the substrate but allow the re-oxidation of the iodine compound. This can be achieved by pumping only the aqueous iodine(I) solution through an electrochemical microreactor and feeding back the reoxidised iodine(III) species as shown in the bottom part of the catalytic cycle. The current in the electrochemical cell can be adjusted so that only the desired iodine(I) to iodine(III) oxidation takes place without affecting the substrate. In the second part of the project, this methodology will be extended to the catalytic generation of chiral iodine(III) reagents for stereoselective reactions. The student will build on our experience in hypervalent iodine chemistry as well as flow electrochemistry to address the challenges in this projectThis highly challenging project will explore new synergies in taking electrochemistry towards catalysis and then further to explore electrocatalytic applications. Flow methodology will be key to the success and with our industrial partners we will make major advancements in the 3.5 years of the project.