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In this work, a diketopyrrolopyrrole‐based 2D covalent–organic framework (COF) is realized and featured with broadband optical absorption and high solar‐thermal conversion performance. Moreover, a 3D hierarchical structure, referred to as COF‐based hierarchical structure (COFHS), is rationally designed to achieve an enhanced photothermal conversion efficiency. In this water evaporator, diketopyrrolopyrrole is immobilized into conjugated COF to achieve enhanced light absorption, whereas a porous PVA network scaffold is utilized to support COF sheets as well as to enhance the hydrophilicity of the evaporator. Due to this structural advantage, COFHS displays a high solar‐to‐vapor energy conversion efficiency of 93.2%. Under 1 sun AM1.5 G irradiation, a stable water evaporation rate of 2.5 kg m–2 h–1 can be achieved. As a proof‐of‐concept application, a water collection device prepared with the COFHS can achieve high solar‐thermal water collection efficiency of 10.2 L m–2 d–1 under natural solar irradiation. The good solar‐thermal conversion properties and high‐water evaporation rate make the COFHS a promising platform for solar‐thermal water production. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]