LAUSR

Abstract A series of bifunctional heterogeneous ionic polymer networks M-Salen-TBB-R were developed by reacting archetype of metal-salophen wtih 1,2,4,5-tetrakis(bromomethyl)benzene, followed by treatment with ionic liquid groups. Various techniques such as 1 H NMR, TGA, CHN elemental analysis, SEM, FT-IR, XPS, and ICP-AES were used to characterize these catalysts. A number of attractive features like highly cross-linked polymer framework, abundant active sites of Lewis acid metal centers and nucleophile Br − , and various N-containing functional cations that endow the resultant catalysts with an expected talent for fixation of carbon dioxide (CO 2 ) under mild and solvent-cocatalyst-free conditions. The catalytic tests by comparison to various synthesized counterparts well demonstrate that this catalyst exhibit excellent activity and selectivity for the cycloaddition of CO 2 with epoxides, and the catalyst can be conveniently recovered and reused. The durable cross-linked network structure of catalyst and the cooperative effect between the metal center, Br − , and organic cations are responsible for the catalyst’s good performances in cycloaddition reactions.