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A supramolecular strategy to construct thermally activated delayed fluorescence (TADF) materials through host-guest charge transfer interactions was proposed. Consequently, a new class of macrocycle namely calix[3]acridan was conveniently synthesized in 90 % yield. The host-guest cocrystal formed by calix[3]acridan and 1,2-dicyanobenzene exhibited efficient TADF properties due to intense intermolecular charge transfer interactions. Moreover, the spatially separated highest occupied molecular orbital and lowest unoccupied molecular orbital resulted in a very small singlet-triplet energy gap of 0.014 eV and hence guaranteed an efficient reverse intersystem crossing for TADF. Especially, a high photoluminescence quantum yield of 70 % was achieved, and it represents the highest value among the reported intermolecular donor-acceptor TADF materials., (© 2022 Wiley-VCH GmbH.)

A strategy of chiral donor-acceptor copolymerization is proposed to develop chiral nonconjugated polymers with thermally activated delayed fluorescence (TADF). Based on this strategy, two pairs of chiral polymers (R,R)-/(S,S)-pTpAcDPS and (R,R)-/(S,S)-pTpAcBP were synthesized. The alternating copolymerization of the chiral donors and acceptors could effectively separate the frontier molecular orbitals, which made the polymers show small ΔE ST of 0.01-0.03 eV and efficient TADF properties. Moreover, the polymers also showed the quantum yield of up to 92 % and the circularly polarized luminescence. The solution-processed circularly polarized organic light-emitting diodes showed circularly polarized electroluminescence signals with high external quantum efficiencies of up to 22.1 % and maximum luminance of up to 34350 cd m -2 . This is the first report of CP-OLEDs based on chiral TADF polymer, which provides a useful and valuable guidance for the development of high-efficiency CPEL polymers., (© 2021 Wiley-VCH GmbH.)

Macrocycles denoted as saucer[n]arenes (n=4,5) were easily synthesized by the one-pot condensation of 2,7-dimethoxynaphthalene (2,7-DMN) and paraformaldehyde in the presence of TFA or catalytic BF 3 ⋅OEt 2 . With 1,1-dimethylpiperidin-1-ium as the template, saucer[4]arene was selectively obtained. Crystal structures show that saucer[n]arenes are all composed of 2,7-DMN moiety bridged by the methylene groups at 1,6-positions: all of the 7-methoxy groups lie on one face, and all of the 2-methoxy groups lie on the other. Saucer[n]arenes exhibit strong fluorescence properties with the quantum yields of 19.6 % and 23.4 %. They form 1:1 complexes with ammonium salts in both solution and solid state (association constant up to 10 5  M -1 in CDCl 3 ). Chiral quaternary ammonium salts can induce the chirality of the dynamically racemic inherently chiral saucer[n]arenes in solution, and thus show mirror-imaged circular dichroism signals and circularly polarized luminescence (CPL) properties., (© 2021 Wiley-VCH GmbH.)