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A novel and efficient catalyst-free and oxidant-free tandem aza-Mannich/cyclization/aromatization reaction of C,N-cyclic azomethine imines with enamides has been developed. This practical one-step protocol enables a simple and environmentally friendly route toward the straightforward synthesis of highly substituted 5,6-dihydropyrazolo[5,1-a]isoquinolines. Different types of enamides and enamines, especially enamides derived from marketed drugs as well as bioactive molecules, are suitable substrates. CB1 cannabinoid receptor antagonist could be synthesized efficiently based on this methodology, illustrating that this would be a practical strategy to synthesize valuable structural motifs. [ABSTRACT FROM AUTHOR]

Hierarchical micro/nanostructures manifest attractive prospects for photocatalytic application. Nevertheless, large-scale hierarchical micro/nanostructures for industrial application with facile, low-cost and eco-friendly routes remain difficult. Herein, nanowire-assembled hierarchical CuO microspheres (HCMAW) are synthesized for the first time by CO32− ions induced synthesis route. The time-dependent SEM images reveal that the growth mechanism for HCMAW is the well-known Ostwald ripening with self-assembly. The specific surface area of the HCMAW is 7.265 m2 g−1, which is higher than that of hierarchical CuO microspheres assembled with nanosheets (HCMAS) (4.952 m2 g−1) prepared by direct self-assembly scheme without the introduction of CO32− ions. Meanwhile, the HCMAW possess strong light absorption around a broadband wavelength from 300 nm to 800 nm. As a result, the photodegradation activity test demonstrates that the HCMAW shows the degradation efficiency of 98.8% for rhodamine B (RhB) under white light irradiation for 30 min in the presence of H2O2 higher than those of HCMAS (66.3%) and commercial CuO (48.3%) under the same condition, which is one of the highest reported till date related to CuO nanomaterials for the degradation of RhB. The novel HCMAW synthesized by the ion-induced protocol is worth being generalized to more assembled hierarchical micro/nanostructures for versatile applications. [ABSTRACT FROM AUTHOR]

Tailored design of photocatalysts with complicated hollow structures is of great importance for promoting environmental remediation. Herein, a monodispersed CuO yolk-shelled structure is synthesized for the first time by simple calcination treatment of a pre-synthesized Cu–EG (ethylene glycol) complex with yolk-shelled structure using a simple, environmentally friendly and glycerol-mediated solvothermal method. Ostwald ripening is the main formation mechanism for the yolk-shelled structure. Such CuO yolk-shelled structures show excellent photocatalytic activity, which is 3.65 times faster than that of the commercial CuO powders and is one of the highest reported photocatalytic activities to date in the CuO nanomaterials for the degradation of rhodamine B (RhB) under visible light irradiation. Such a preferable photocatalytic activity is mainly attributed to the unique yolk-shelled structure, which can enable higher multiple light reflections and scattering between the outer spherical shell and the interior core compared with commercial CuO powders, to provide a more efficient way to enhance light-harvesting efficiency. [ABSTRACT FROM AUTHOR]

In this work, novel rice-shaped porous ZnMn2O4 microparticles made of nanoparticles were successfully prepared for the first time by the calcination of Zn0.33Mn0.67CO3 precursors synthesized using a facile triethanolamine-assisted solvothermal method. The effect of solvothermal reaction time on the crystallinity and morphology of Zn0.33Mn0.67CO3 precursors is discussed. The obtained ZnMn2O4 microparticles have lengths of ca. 1.6 μm and widths of ca. 0.9 μm, while the primary nanoparticles are in sizes of ca. 25–70 nm. As a potential anode material for lithium-ion batteries, the ZnMn2O4 microparticles give a large reversible discharge capacity of 892 mA h g−1 at 0.2 A g−1, superior cyclability (95% capacity retention after 550 cycles at 2 A g−1), and excellent rate capability (571 mA h g−1 at 5 A g−1). The outstanding electrochemical performances of the microparticle materials benefit from the suitable micro-/nanoparticle sizes, hierarchical porous structures, and strong interconnected 3D frameworks, which shorten the path lengths for ionic transport, accommodate volume expansion/contraction, and maintain the structural integrity of electrodes during the cycling process. [ABSTRACT FROM AUTHOR]