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Here, we combined the merits of emergent excitation-dependent (ExD) emission and circularly polarized luminescence to develop an excitation-dependent circularly polarized luminescence (ExD CPL) material showing unique features. A series of acylhydrazones based on a chiral tartaric skeleton was designed and found to self-assemble into helical nanostructures through non-covalent bonds. The helical assemblies showed ExD CPL due to the cooperation of chirality transfer and excited state intramolecular proton transfer (ESIPT). Remarkably, not only the emission wavelength could be tuned by the excitation wavelength but the handedness of CPL could be modulated in an inverted or ON/OFF manner as well, thus leading to the first example of an ExD inverted or ON/OFF switchable CPL system. Time-dependent density functional theory (TD-DFT) calculations were carried out to explain the inversion of ExD CPL. This work provided a new insight into the unprecedented handedness controllable ExD CPL, which showcased a new paradigm of the advanced CPL materials., (© 2022 Wiley-VCH GmbH.)

Complexation of racemic 2,6-helic[6]arene 1 and its hexamethyl-substituted derivative 2 with quaternary ammonium salts, N-heterocyclic salts, and tetracyanoquinodimethane have been described in detail. It was found that host 2 could form stable complexes with acetyl choline, thiaacetyl choline, N,N,N-trimethylbenzenammonium salt, pyridinium, and 4,4'-bipyridinium salts in solution and/or in the solid state. The unsubstituted macrocycle 1 showed more significant complexation with the widely tested quaternary ammonium salts and N-heterocyclic salts, and exhibited stronger complexation towards the guests than its derivative 2. Moreover, it was found that macrocycle 1 and its derivative 2 could also complex with neutral electron-deficient tetracyanoquinodimethane (TCNQ), and the association constants were determined to be 2840±94 and 1358±46 m -1 , respectively. These results could make this new macrocycle and its derivatives find wide applications in the design and construction of functional supramolecular assemblies., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

New triptycene-derived oxacalixarene H1 was efficiently synthesized by a template cyclization step, and anilino-substituted macrocycle H2 was subsequently afforded through straightforward nucleophilic displacement of the active chlorine atom in H1. Oxacalixarene H1 adopts a fixed boat-like 1,3-alternate conformation and shows moderate complexation abilities towards various bipyridinium salts. However, the affinities of H2 towards the guests were found to be substantially stronger, which could be tentatively attributed to the additional hydrogen-bonding site, π-π stacking site, and especially the increased electron richness of the host. Furthermore, the acid-base switchable complexation process between H1 and the bipyridinium salt was also realized, which could potentially facilitate the construction of high-level stimuli-responsive supramolecular structures based on the newly synthesized oxacalixarene., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A new class of chiral macrocyclic arene composed of three chiral 2,6-dihydroxyltriptycene subunits bridged by methylene groups was designed and synthesized. Structural studies showed that the macrocyclic molecule adopts a hex-nut-like structure with a helical chiral cavity and highly fixed conformation. Efficient resolution was achieved through the introduction of chiral auxiliaries to give a couple of enantiopure macrocycles, which exhibited high enantioselectivity towards three pairs of chiral compounds containing a trimethylamino group., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)