Crystalline mate for structure elucidation of organic molecules

Summary

Single-crystal X-ray diffraction (SCXRD) analysis is the most definitive structure determination method, yet it hinges upon the success of crystal growth and that can sometimes be challenging for volatile or complicated molecules. Here, we report a highly fluorinated cyclic trinuclear Ag(I) pyrazolate complex (Ag₃Pz₃) with strong π-acidity as a crystalline mate for structural elucidation of those having difficulty crystallizing on their own. Dozens of oxygenated organic molecules were smoothly co-crystallized with Ag₃Pz₃, regardless of their sizes and shapes. Their chemical structures were unambiguously determined by subsequent SCXRD analysis. Ag₃Pz₃ is highly adaptive and can pack with organic molecules in four different types of binding modes according to their structural and electronic attributes. Moreover, Ag₃Pz₃ is a robust crystalline mate and can be directly employed for the co-crystallization of mixtures without tedious separation, as exemplified by the successful identification of individual components in mixtures and even the crude extract of natural medicine.