Development of recoverable and recyclable Fe₃O₄‐supported organocatalysts for ring‐opening polymerization

Abstract

An iminotris(dimethylamino)phosphorane (HMP1) phosphazene superbase has been anchored onto poly(hexachlorocyclotriphosphazene‐co‐4,4′‐sulfonyldiphenol) (PZS)‐coated Fe3O4 magnetic nanoparticles (MNPs) through efficient phosphorous‐chloride (from PZS surface) and imino (from HMP1) reaction. Subsequently, these novel heterogeneous Fe3O4@PZS@HMP1 catalysts have been successfully utilized in the ring‐opening polymerization of ε‐caprolactone (ε‐CL) and δ‐valerolactone (δ‐VL). Notably, such catalysts can be easily removed from the reaction mixture and reused 3 times without obvious activity loss.