Hydroquinones as halogen-bonding catalysts for radical perfluroalkylation reactions

Abstract

Developing a better understanding of how hydroquinones serve to catalytically activate alkyl halides through halogen-bonding interaction to form visible-light absorbing charge-transfer complexes (CTC) holds immense value. In this presentation, a CTC that occurs through halogen-bonding interactions will be highlighted. A CTC is the generation of a new ground state aggregate by the association of a electron-rich compound and an electron-poor compound in solution. The CTC can absorb in the visible light region (400-700 nm), while individual substrates are unable to. Therefore, the CTC provides an alternative strategy for performing visible-light-mediated reactions. In the Pitre Lab, we are working to develop catalytic systems for charge-transfer photochemistry. In this work, charge-transfer photochemistry that includes the use of hydroquinones (HQs) as catalysts that activate alkyl bromides towards visible-light irradiation through halogen-bonding interactions is presented. The main goal of our project is to develop a system with iodide salts that undergo a substitution reaction on the alkyl bromide to make an alkyl iodide in situ, since bromides are less reactive than iodides towards halogen bonding. Later works will focus on expanding the scope of these reactions and work to determine the optimal conditions.