The cycloaddition reaction between epoxides and CO_(2) is an effective method to utilize CO_(2) resource.Covalent organic frameworks(COFs)provide a promising platform for the catalytic CO_(2) transformations on accoun...The cycloaddition reaction between epoxides and CO_(2) is an effective method to utilize CO_(2) resource.Covalent organic frameworks(COFs)provide a promising platform for the catalytic CO_(2) transformations on account of their remarkable chemical and physical properties.Herein,a family of novel vinylene-linked ionic COFs named TE-COFs(TTE-COF,TME-COF,TPE-COF,TBE-COF)has been facilely synthesized from N-ethyl2,4,6-trimethylpyridinium bromide and a series of triphenyl aromatic aldehydes involving different numbers of nitrogen atoms in the central aromatic ring.The resulting catalyst TTE-COF with excellent adsorption capacity(45.6 cm3·g^(-1),273 K)exhibited outstanding catalytic performance,remarkable recyclability and great substrate tolerance.Moreover,it was also observed that the introduction of nitrogen atom in the precursor led to a great improvement in the crystallinity and CO_(2) adsorption capacity of TE-COFs,thus resulting to a progressively improved catalytic performance.This work not only illustrated the influence of monomer nitrogen content on the crystallinity and CO_(2) adsorption capacity of TE-COFs but also provided a green heterogeneous candidate for catalyzing the cycloaddition between CO_(2) and epoxides,which shed a light on improving the catalytic performance of the CO_(2) cycloaddition reaction by designing the covalent organic frameworks structures.展开更多
基金financially supported by the Guangdong Basic and Applied Basic Research Foundation(Grant No.2022A1515011606)the Haihe Laboratory of Sustainable Chemical Transformations.
文摘The cycloaddition reaction between epoxides and CO_(2) is an effective method to utilize CO_(2) resource.Covalent organic frameworks(COFs)provide a promising platform for the catalytic CO_(2) transformations on account of their remarkable chemical and physical properties.Herein,a family of novel vinylene-linked ionic COFs named TE-COFs(TTE-COF,TME-COF,TPE-COF,TBE-COF)has been facilely synthesized from N-ethyl2,4,6-trimethylpyridinium bromide and a series of triphenyl aromatic aldehydes involving different numbers of nitrogen atoms in the central aromatic ring.The resulting catalyst TTE-COF with excellent adsorption capacity(45.6 cm3·g^(-1),273 K)exhibited outstanding catalytic performance,remarkable recyclability and great substrate tolerance.Moreover,it was also observed that the introduction of nitrogen atom in the precursor led to a great improvement in the crystallinity and CO_(2) adsorption capacity of TE-COFs,thus resulting to a progressively improved catalytic performance.This work not only illustrated the influence of monomer nitrogen content on the crystallinity and CO_(2) adsorption capacity of TE-COFs but also provided a green heterogeneous candidate for catalyzing the cycloaddition between CO_(2) and epoxides,which shed a light on improving the catalytic performance of the CO_(2) cycloaddition reaction by designing the covalent organic frameworks structures.
