Scalable and Recyclable Heterogeneous Organo-photocatalysts on Cotton Threads for Organic and Polymer Synthesis

As a highly efficient and environmentally friendly technology to address the challenges of sustainable chemistry and engineering, heterogeneous visible-light photoredox catalysis has been of great potential in organic and polymer synthesis. Eosin Y (EY), one of the commonly used organo-photoredox catalysts, has been immobilized onto commercial cotton threads via a straightforward method and single-step coupling reaction to prepare a scalable and recyclable heterogeneous photocatalyst. The immobilized EY is capable of generating singlet oxygen for organic transformations (e. g. oxidation of thioethers) in the presence of molecular oxygen, and effectively catalysing visible-light photoinduced electron/energy transfer-reversible addition-fragmentation chain transfer polymerizations of various functional monomers for the synthesis of well-defined polymers in diverse green solvents. Facile separation and recovery of the cotton thread supported EY enable the reuse of the catalyst over multiple reaction cycles with well-retained catalytic efficiency.