Synthesis of optically active 2,2′‐diselenocyanato‐1,1′‐binaphthyl and its molecular structure. Hypervalent nature of divalent selenium atom in crystal state

Abstract 2,2′‐Diselenocyanato‐1,1′‐binaphthyl(1), the first selenium‐containing binaphthyl derivative, has been synthesized in optically active form the corresponding diamine by diazotization followed by the reaction with potassium selenocyanate. Its molecular structure is determined by X‐ray diffraction method. It is revealed that selenium atoms have hypervalent penta‐coordination in the crystal.