-methylpyrrolidone (NMP) is an excellent advanced solvent that can be easily absorbed by the human body and has the characteristics of flammability and explosion. To reduce the risk, the environmental concentrations of NMP need to be measured. A series of covalent organic frameworks (COF) connected by an imine bond have been successfully prepared at room temperature by changing the synthesis time catalyzed by scandium(III) trifluoromethanesulfonate (Sc(OTf)