“…Their size-specific electron-rich hydrophobic cavities can selectively bind certain molecules through host–guest interactions [ 26 , 27 , 28 ]. The host–guest properties of macrocycles have been extensively applied in the fields of drug delivery [ 29 , 30 , 31 ], water purification [ 32 ], self-assembly [ 33 ], photochromism [ 34 , 35 ], and substance detection [ 36 , 37 , 38 , 39 ]. In particular, the development of pillararene-based macrocyclic arenes has increased rapidly since they were first reported on in 2008, and a variety of expanded versions of macrocyclic arenes, such as leaning pillar[6]arene [ 40 ], biphenyl-extended pillar[6]arene [ 41 ], geminiarenes [ 42 ], leggero pillar[5]arene [ 43 ], and hybrid [n] arenes [ 44 ], have been synthesized.…”