Recent advances in structurally elaborate triptycenes, triptycene-containing polymers and assemblies: structures, functions and applications

Triptycene, a rigid propeller-shaped molecule, was first synthesized in the early 1940s. More recently, many triptycene-containing polymers and molecular assemblies have been developed for a wide range of applications, including guest recognition, material transport, separation, catalysis, and as device components. The advantages of triptycenes lie in their ability to introduce a variety of functional groups on their three-dimensional backbone, with changes in substitution patterns as well as the type of substituents present having a significant impact on the material properties. In this review, we describe the synthesis of triptycene derivatives and polymers, detailing selected examples of triptycene-containing functional polymers. We also focus on the construction of triptycene-based two-dimensional assemblies and polymers, where space-filling designs based on rigid propeller-shaped skeletons are essential. Through a thorough literature survey, future directions and possibilities for the development of triptycene-containing functional materials are discussed. Triptycene-containing polymers featuring a rigid propeller-shaped structure have attracted attention for a wide range of potential applications including guest recognition, material transports, separations, catalysis, and organic electronics. Herein, with a thorough literature survey, we present the synthesis of the various types of triptycenes that provide components for functional polymers. We particularly focus on triptycene-containing polymers and two-dimensional assemblies based on the space-filling design that uses nested packing. Future perspectives on the functionalities brought about by the design of triptycene-containing polymers and molecular assemblies are also discussed.