Triple Helicene Cage: Three‐Dimensional π‐Conjugated Chiral Cage with Six [5]Helicene Units

A three‐dimensional π‐conjugated chiral cage with six [5]helicene units (a triple helicene cage) was synthesized for the first time. Taking advantage of the Yamamoto coupling reaction, the triflate‐substituted triple [5]helicene, a strained and preorganized precursor, was dimerized to afford the target compound. Single‐crystal X‐ray diffraction analysis revealed the unique structural features of the triple helicene cage: a cage‐shaped rigid structure with outer helical grooves and an inner chiral cavity. All‐P and all‐M enantiomers were separated successfully by HPLC over a chiral column and their chiroptical properties were characterized by circular dichroism spectra.