Dynamic control of circumrotation of a [2]catenane by acid‐base switching

Abstract

AbstractDynamic control of the motion in a catenane remains a big challenge as it requires precise design and sophisticated well‐organized structures. This paper reports the design and synthesis of a donor‐acceptor [2]catenane through mechanical interlocking, employing a crown ether featuring two dibenzylammonium salts on its side arms as the host and a cyclobis(paraquat‐p‐phenylene) (CBPQT ⋅ 4PF6) ring as the guest molecule. By addition of external acid or base, the catenane can form self‐complexed or decomplexed compounds to alter the cavity size of the crown ether ring, consequently affecting circumrotation rate of CBPQT ⋅ 4PF6 ring of the catenane. This study offers insights for the design and exploration of artificial molecular machines with intricate cascading responsive mechanisms.