Theoretical Study On The Catalysis Of The CO₂ Fixation With Aziridines By Metal-substituted HKUST-1

As a renewable,inexpensive,nontoxic and safe C1 feedstock,the conversion of CO₂is extremely important and has received more and more attention.In particular,the cycloaddition of CO₂with aziridines to afford oxazolidinones,which can serve as the important intermediates in organic synthesis and medicinal chemistry,has attracted a great deal of interest.Cu-HKUST-1,a well-known metal–organic framework（MOF）,has been very recently shown to have the great potential in catalyzing the cycloaddition of CO₂with aziridines.In order to develop more effective and diverse catalysts,in this work,we carried out the first computational screening study（at M06-2X//B3LYP level）on the cycloaddition of CO₂with aziridines under a series of metal-substituted HKUST-1（Ag,Mo,Cr,W,Nb,Ru,Rh,Y,Sc,V,Tc,Cd,Ti,Mn,Zn,Fe and Zr）MOFs and tetrabutylammonium bromide（TBAB）as a co-catalyst.For all the considered catalytic systems,the ring-opening of aziridine is calculated to be rate-determining step.Up to 11 M-HKUST-1 systems,i.e.,Rh(31.87 kcal mol^-1),Y(31.02 kcal mol^-1),Sc(30.50 kcal mol^-1),V(30.02 kcal mol^-1),Tc(29.90 kcal mol^-1),Cd(29.80 kcal mol^-1),Ti(29.32 kcal mol^-1),Mn(29.05 kcal mol^-1),Zn(28.29 kcal mol^-1),Fe(27.85 kcal mol^-1)and Zr(25.09 kcal mol^-1),possess the lower ring-opening barrier heights than the original Cu-HKUST-1(32.90 kcal mol^-1),indicative of their superior catalytic ability to the original Cu-HKUST-1 in theory.With the lowest ring-opening barrier,Zr-HKUST-1 is strongly advocated for future synthetic and catalytic studies.