Chalcogen Bonding Mediated Chiral Recognition and Enantioenrichment of Organoselenocyanates

Abstract

Chalcogen bonding (ChB) is recognized as an essential driving force in the Group VIA element-containing materials. The multiple σ-holes with high directionality endow ChB with potentials in chiral functions including recognition, sensing and chiroptical materials. Herein we employ ChB to enable chiral sensing and enantioenrichment and separation of organoselenocyanates. A library of organic selenocyanate derivatives were constructed, of which complexation with a chiral phenanthroline conjugated foldamer was driven by ChB aided by hydrogen bonding and π-stacking forces. The deep chiral environment of the foldamer enables binding affinity bias towards enantiopure selenocyanates that give differential spectroscopic output and binding constants. ChB mediated chiral recognition also shows impacts on self-assembly, that the emergence of macroscopic chirality is controlled by the enantiomeric matching effect. Finally, we realized efficient enantioenrichment of the organoselenocyanates utilizing the ChB assisted chiral recognition for the first time, which establishes a new route in the chiral separation of Se containing pharmaceuticals by σ-hole interactions.