Host-Guest chemistry based on solid-state pillar[n]arenes

Pillar[n]arenes, which were first reported by our group in 2008, are a new type of pillar-shaped host molecule in host-guest chemistry with versatile and unique host-guest behaviors. Host-guest complexation is mostly investigated in solution systems, where both the host and guest molecules are normally dissolved in solvent. Compared with normal host-guest complexation in solvents, solid-state host-guest complexation can offer the following advantages and characteristics: (i) Cavity-size dependent host- guest complexation, (ii) efficient host-guest complexation, and (iii) easy host-guest complex isolation and solid-state pillar[n]arene reuse. In this review, we discuss the recent development of solid-state host-guest complexation using crystalline pillar[n]arenes, two or three-dimensional networks containing pillar[n]arenes, including hydrogen-bonded organic frameworks (HOFs), and metal-organic frameworks (MOFs), pillar[n]arene-assembled surfaces, and solid-state organic polymers containing pillar[n]arenes. (C)& nbsp;2022 Elsevier B.V. All rights reserved.