Host-Guest Recognition and Fluorescence of a Tetraphenylethene-Based Octacationic Cage.
We report the synthesis and characterization of a three-dimensional tetraphenylethene-based octacationic cage that shows host-guest recognition of polycyclic aromatic hydrocarbons (e.g. coronene) in organic media and water-soluble dyes (e.g. sulforhodamine 101) in aqueous media through CH⋅⋅⋅π, π-π, and/or electrostatic interactions. The cage⊃coronene exhibits a cuboid internal cavity with a size of approximately 17.2×11.0×6.96 Å3 and a "hamburger"-type host-guest complex, which is hierarchically stacked into 1D nanotubes and a 3D supramolecular framework. The free cage possesses a similar cavity in the crystalline state. Furthermore, a host-guest complex formed between the octacationic cage and sulforhodamine 101 had a higher absolute quantum yield (ΦF =28.5 %), larger excitation-emission gap (Δλex-em =211 nm), and longer emission lifetime (τ=7.0 ns) as compared to the guest (ΦF =10.5 %; Δλex-em =11 nm; τ=4.9 ns), and purer emission (ΔλFWHM =38 nm) as compared to the host (ΔλFWHM =111 nm).
['Duan|Honghong|H|', 'Li|Yawen|Y|', 'Li|Qingfang|Q|', 'Wang|Pinpin|P|', 'Liu|Xueru|X|', 'Cheng|Lin|L|', 'Yu|Yang|Y|', 'Cao|Liping|L|http://orcid.org/0000-0002-1747-6107']
fluorescence aggregation-induced emission cationic cages host-guest systems supramolecular chemistry