Chiral Macrocyclic Organocatalysts for Kinetic Resolution of Disubstituted Epoxides with Carbon Dioxide

Among chiral macrocycles 1 synthesized, 1m with the 3,5-bis­(trifluoromethyl)­phenylethynyl group was the best organocatalyst for the enantioselective synthesis of cyclic carbonates from disubstituted or monosubstituted epoxides and CO2. The X-ray crystal structure of 1m revealed a well-defined chiral cavity with multiple hydrogen-bonding sites that is suitable for the enantioselective activation of epoxides. A catalytic cycle proposed was supported by DFT calculations.在所合成的手性大环化合物1中，带有3,5-双(三氟甲基)苯乙炔基的1m是催化双取代或单取代环氧化物与二氧化碳（CO₂）对映选择性合成环状碳酸酯的最优有机催化剂。 1m的X射线晶体结构显示其具有结构明确的手性空腔，该空腔带有多个氢键作用位点，可用于环氧化物的对映选择性活化。 所提出的催化循环机制得到了密度泛函理论（Density Functional Theory，DFT）计算的佐证。