A new type of Lewis acid–base bifunctional M(salphen) complexes (M=Zn^II, Cu^II, and Ni^II) pending two N‐methylhomo‐ piperazine groups as nucleophiles were prepared by a one‐pot method. The Zn(salphen) complexes proved to be efficient and recyclable homogeneous catalysts towards the solvent‐free synthesis of cyclic carbonates from epoxides and CO₂ in the absence of a co‐catalyst. The catalysts can be easily recovered and five times reused without significant loss of activity and selectivity.

中文翻译：

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一种新型的路易斯酸碱双功能M（沙芬）（M = Zn，Cu和Ni）催化剂，用于CO2固定

通过一锅法制备了一种新型的路易斯酸碱双官能M（salphen）配合物（M = Zn ^II，Cu ^II和Ni ^II），其中有两个N-甲基高哌嗪基团为亲核试剂。事实证明，在没有助催化剂的情况下，Zn（salphen）络合物是高效且可回收的均相催化剂，可用于由环氧化物和CO ₂无溶剂合成环状碳酸酯。催化剂可以很容易地回收并可以重复使用五次，而活性和选择性却没有显着降低。