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Towards unexplored intermolecular n→π* interactions, presented herein are the synthesis, structure, self‐assembly and function of a multicarbonyl‐containing macrocycle calix[2]arene[2]barbiturate 1. X‐ray single crystal diffraction reveals the presence of Cl⋅⋅⋅C=O interactions in CH2Cl2⊂1 host‐guest complex and multiple intermolecular C=O⋅⋅⋅C=O interactions between molecules 1 in crystalline state. The intermolecular C=O⋅⋅⋅C=O interactions as attractive driving force led to unprecedented self‐assembly of nanotube with diameter around 1.4 nm and inner surface engineered by aromatic rings. SEM and TEM images of the self‐assembly of 1 demonstrated temperature‐dependent morphologies which allows the observation of spheres at 25 °C and rods at 0 °C, respectively. XRD analysis indicated consistent hexagonal patterns in the self‐assembly and single crystal lattice, indicating the nanotubes driven by C=O⋅⋅⋅C=O interactions constitute the basic structural architectures of both aggregates. The nanoscopic tubes (pores) formed in the rodlike single crystal engendering the separation of moving dyes were preliminarily investigated by a single‐crystal chromatography and crystal‐packed column chromatography. [ABSTRACT FROM AUTHOR]

Bowl inversion is a unique property of buckybowls. The polarity and assembly configuration of buckybowls are reversed after bowl inversion. So far, this unique phenomenon has been studied in solution and on surface, but not in solid state due to spatial constraint. Now a series of exo‐type supramolecular assemblies of trithiasumanene and nanographene are investigated. Tuning the electron density of the nanogaphene component was found to directly affect the binding constant of the complex. Reversible bowl inversion in the solid state was then successfully achieved by subjecting the trithiasumanene–nanographene assembly with the weakest binding strength to repeated heating–cooling cycles, which was unambiguously observed by single crystal X‐ray diffraction. [ABSTRACT FROM AUTHOR]

A di-vanadium-substituted Lindqvist-type polyoxometalate [Cu(C12H8N2)2]2[V2W4O19]·4H2O (1) was hydrothermally synthesized and characterized structurally by single crystal X-ray diffraction analysis. X-ray photoelectron spectroscopy and energy disperse spectroscopy tests further prove the existence of vanadium. Ultraviolet photoelectron spectroscopy and density functional theoretical studies indicate that the energy level of 1 matches well with the conduction band of the TiO2. Furthermore, considering the semiconductor-like nature of 1 and the introduction of transition metal element Cu synchronously extends the absorption to the visible region, which should also be beneficial to the photovoltaic device performance. 1-Doped TiO2 composites (denoted as 1@TiO2) have been successfully fabricated by a simple sol–gel method, and introduced into the dye-sensitized solar cells (DSSCs) as co-sensitizers in N719-sensitized photoanodes by mixing 1@TiO2 with P25 nanoparticles with different weight ratios to enhance the photoelectric conversion efficiency. The investigations show that the DSSC assembled with 1@TiO2/19P25 photoanode has the best performance and the overall improvement of the efficiency is 21.6% compared with pure P25. Furthermore, the electrochemical impedance spectroscopy and open-circuit voltage decay investigations show that the cosensitization of 1 and N719 can promote electron transfer and restrain charge recombinations in the DSSCs, resulting in a longer electron lifetime. [ABSTRACT FROM AUTHOR]

We report a special example of chemiluminescent dearomatisation reaction between metalated pyrrole and 1O 2. The mechanism of photooxygenation of complex 1 is proposed via a stepwise [2+2]-cycloaddition of 1O 2 following by ring-opening to generate a ketoamide complex 2. [Display omitted] Visible-light-mediated dearomatisation of pyrroles is a powerful strategy for the synthesis of pharmaceuticals and bioactive compounds. Herein we present the chemiluminescent reaction between pyrrole metalated-Ir(III) complex [Ir(K 2 C, N -DPP)(H)(Cl)(PPh 3) 2 ] (1) and singlet oxygen to form a ketoamide complex [Ir(K2 C, N -ketoamide)(H)(Cl)(PPh 3) 2 ] (2). Complex 2 are fully characterized by NMR and single crystal X-ray diffraction analysis. The reaction mechanism of metalated pyrrole-singlet reaction upon irradiation is studied by experiment and DFT calculations. [ABSTRACT FROM AUTHOR]