Continuous-Flow Synthesis of Pyrylium Tetrafluoroborates: Application to Synthesis of Katritzky Salts and Photoinduced Cationic RAFT Polymerization
Carlo Sambiagio, Matteo Ferrari, Koen van Beurden, Nicola Della Ca’, Jack van Schijndel, Timothy Noël
Abstract
Katritzky salts have emerged as effective alkyl radical sources upon metal- or photocatalysis. These are typically prepared from the corresponding triarylpyrylium ions, in turn an important class of photocatalysts for small molecules synthesis and photopolymerization. Here, a flow method for the rapid synthesis of both pyrylium and Katrizky salts in a telescoped fashion is reported. Moreover, several pyrylium salts were tested in the photoinduced RAFT polymerization of vinyl ethers under flow and batch conditions.
Topics & Concepts
ChemistryCationic polymerizationPolymerizationPhotopolymerReversible addition−fragmentation chain-transfer polymerizationPhotochemistryRadical polymerizationPhotocatalysisRaftPolymer chemistryCombinatorial chemistryOrganic chemistryCatalysisPolymerInnovative Microfluidic and Catalytic Techniques InnovationAdvanced Polymer Synthesis and CharacterizationRadical Photochemical Reactions