Fabrication of Flexible Co‐salen Integrated Polymers for Hydration of Epoxides and Alkynes via Cooperative Activation

Abstract

AbstractMost cross‐linked polymers with integrated active sites in the network have poor flexibility, which inhibits their applications in catalysis involving a cooperative activation pathway. Herein, a flexible organic polymer with high concentration of salen ligand in the network (SOP) was successfully synthesized by the reaction of meso‐1,2‐diphenylethylenediamine and 1,3,5‐tris(3’‐tert‐butyl‐4’‐hydroxy‐5’‐formylphenyl)benzene. The post‐synthesis coordination with CoII followed by further oxidation results in the formation of SOP−Co−OTs. The large amounts uptake of benzene of SOP and variation of the BET surface area after coordination with different metal cations confirmed the network flexibility. Consequently, SOP−Co−OTs could efficiently catalyze the epoxides hydration to afford turnover frequency up to 2400 h−1 via cooperative activation. Furthermore, SOP−Co−OTs works cooperatively with Amberlyst‐15 in the hydration of phenylacetylene to afford higher yield than homogeneous Co‐salen. Our primary results suggest the potential applications of flexible polymer catalysts in reactions involving cooperative activation pathway.