TRR 325:  Assembly Controlled Chemical Photocatalysis

• Subject Area: Chemistry
• Term: since 2021
• Website: Homepage
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 444632635

It is the goal of chemical photocatalysis to create new structures and to explore novel reactions by capturing light, ideally visible light. The dramatic development in the field over the past ten years has changed the way we do organic synthesis. Light-driven reactions allow the facile generation of reactive intermediates, which are key components in bond-forming events. The selectivity and productivity of photocatalytic transformations depend significantly on the interaction between the substrate and the catalytically active species before, during, and after light excitation. However, for most reported photocatalytic and photochemical reactions these interactions are ill-defined or unknown. This CRC aims to traverse new frontiers in photocatalysis for organic synthesis by designed control of catalyst-substrate interactions. Results of this research initiative will enable a broader application of light-initiated chemical transformations as an essential tool for the selective and efficient synthesis of complex molecules in academic research and industrial production. The interdisciplinary research approach combines experimental, spectroscopic, and computational techniques for the analyses and applications of different catalyst-substrate interactions including reversible coordination and reversible covalent bonding, hydrogen bonding, ionic and dipolar interactions, London forces, and solvation. This will allow for a more rational design of improved photochemical and photocatalytic organic reactions. The development of photocatalysts for solar fuel generation, materials for photovoltaic applications, and chemical models of biological photosynthesis are excluded from the research programme. The planned CRC builds on the experience of several PIs from the research training group (RTG) 1626 “Chemical Photocatalysis”, which contributed to the development of the field of research over the last nine years, and includes additional expertise now required to develop the next generation of photocatalytic and photochemical reactions in organic synthesis.

• DFG Programme: CRC/Transregios

Current projects

• A01 - Visible Light Mediated Coupling Reactions via Photoexcitation of Cu(I)-Substrate Assemblies (Project Head Reiser, Oliver )
• A02 - Visible Light Induced Homolysis (VLIH) of 3d-Metal-Substrate Complexes (Project Head Reiser, Oliver )
• A03 - Photocatalysis with Reversibly Coordinating Cerium Complexes (Project Head König, Burkhard )
• A04 - 3d Transition Metal Complexes for Photocatalysis: The Crucial Influence of Catalyst-Substrate Assembly on Reactivity (Project Head Wolf, Robert )
• A05 - Monitoring and Exploiting Short-lived Intermediates in Assembly-Controlled Photocatalytic Processes (Project Head Nürnberger, Patrick )
• B01 - Chromophore Activation by Lewis Acid Coordination (Project Head Bach, Thorsten )
• B02 - Hydrogen Bonds and Ion Pairs in Enantioselective Photochemistry (Project Head Bach, Thorsten )
• B03 - NMR spectroscopic tools to detect Brønsted/Lewis acid-base preorganization in photocatalysis (Project Head Gschwind, Ruth M. )
• B04 - A Photoredox/Lewis-Acid Hybrid Catalyst Design for the Covalent Activation of Alkenes (Project Head Breder, Alexander )
• B05 - Tuning Radical Reactivity in Photocatalytic Transformations of NHC-Activated Substrates (Project Head Rehbein, Julia )
• B06 - Base-Promoted Oxidative PCET Remote Functionalization (Project Head Zeitler, Kirsten )
• B07 - Photoexcitation of Reduced, Molecular Flavins and their Application in Catalysis (Project Head Storch, Golo Trutz Benjamin )
• B08 - Transient Absorption on Multiple Timescales – from Ultrafast Relaxation to Charge Transfer Processes (Project Head Hauer, Jürgen )
• C01 - Taming Reactive Intermediates in Photocatalysis by Assembly Control (Project Head König, Burkhard )
• C02 - Charge Transfer Complexes in Homogeneous and Heterogeneous Photocatalysis by NMR Spectroscopy (Project Head Gschwind, Ruth M. )
• C03 - Photochemical Polyene Cyclizations in Microheterogenous, Fluorinated Environments (Project Head Gulder, Tanja )
• C05 - Environmental effects on excited states dynamics: Insights and benchmarks from quantum chemistry (Project Heads Ochsenfeld, Christian ;  de Vivie-Riedle, Regina )
• C06 - Expanding the Enzymatic Photoredox Repertoire with PQQ-Dependent Dehydrogenases (Project Head Zeymer, Cathleen )
• MGK - IRTG (Project Head König, Burkhard )
• Z - Central Tasks of the Collaborative Research Centre (Project Head Bach, Thorsten )

• Applicant Institution: Technische Universität München (TUM)
• Co-Applicant Institution: Universität Regensburg
• Participating University: Ludwig-Maximilians-Universität München; Universität Leipzig
• Spokesperson: Professor Dr. Thorsten Bach