Stereoselective Synthesis of Pillar[4]arene[1]cis‐diepoxy‐p‐dione and X‐Ray Crystal Structure of Host–Guest System

Herein, we successfully develop a novel route to give rise to polarity for the pillararenes by the introduction of oxygenated functionalities into pillar5]arene to stereoselectively synthesize the pillar4]arene1]cis ‐diepoxy‐p ‐dione. Its host–guest properties with different dinitrile molecules were also investigated and characterized by NMR and X‐ray crystallography.