"The aim of this proposal is to develop new and sustainable synthetic methods employing visible light as the sole energy source. MacMillan has demonstrated this concept by merging photoredox catalysis with organocatalytic protocols to perform previously unknown direct enantioselective carbonyl α-functionalization reactions. Building upon this precedent the outgoing phase of this project seeks to incorporate this photoredox process into an organocascade catalysis sequence to generate synthetically valuable intermediates that are relevant in medicinal and natural product chemistry. In this project we propose the merger of iminium ion catalysis with a photoredox-organocatalytic process to generate enantioenriched aldehydes that are α- and β-functionalized from inexpensive and readily available starting materials. This would constitute the first example of an organocascade sequence involving a photoredox system and its compatibility with iminium ion catalysis.During the return phase photoredox catalysis will be merged with gold chemistry to develop a new methodology for the construction of biaryl systems, which are ubiquitous in pharmaceuticals and organic materials. This protocol will provide a complementary procedure to the Au-catalyzed arylation reaction disclosed by the Lloyd-Jones group, which utilizes arylsilanes as coupling partners. This approach presents a more sustainable approach to biaryl formation that generates less chemical waste and involves readily available starting materials. Overall, the pioneering nature of this proposal as well as the opportunity to forge new international collaborations between two leading research institutions would contribute significantly to scientific excellence in Europe. Moreover, the fellow would develop and gain numerous skills that will ensure his pursuit of an independent research career is prosperous."