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Simultaneously fusing pyrrole and pyridine at perylene's opposite edges is facilely achieved in this work, yielding PerNN and its various derivatives. All targets demonstrate global diamagnetic ring current. Benefiting from a spatially separated donor–acceptor group within one planar skeleton, PerNN exhibits efficient narrow blue emission and columnar stacking. More importantly, its alkylated derivatives PerNN-MeCl and PerNN-MeI display anti-Kasha dual emission responsive to solvent polarity and reveal highly efficient ROS generation, paving the way to great potential applications. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) porous materials with nano/μ structured fibre-fibre interactions are promising candidates for tissue engineering scaffolds, material separation diaphragms, energy storage and dissipation systems, and catalyst materials, etc . However, the conventional electrospinning process is mainly focused on the surface depositions of 2D nanofibrous mats. In this work, we propose a novel methodology of creating 3D nanofibrous networks, featured with neutralization and self-assembly of electrospun nanofibers by means of dual electrospinning from oppositely charged polymer jets. Using a fine-tuned upward airflow from a controllable heat source, we have successfully counterbalanced the gravity as well as the electrostatic force acting on the inflated intertwined jets clusters, which permits the mass production of 3D nanofibrous materials. We also experimentally measured sound absorption coefficients of the 3D nanofibrous networks in a standing wave tube and observed a nontrivial improvement of sound absorption in the audible frequencies ranging from 400 to 900 Hz by comparing with commercial muffler materials. [ABSTRACT FROM AUTHOR]

A convenient and mild approach for the construction of ynones via N -iodosuccinimide (NIS)-mediated oxidation of propargyl alcohols has been described. This reaction could furnish the ynone products with a diversity of functional groups in moderate to excellent yields, and the flexibility of this method was demonstrated by the gram-scale experiment and further transformation.

A series of constrained geometry O-functionalized cyclopentadienylchromium complexes ( 1 - 6 ) and a S-functionalized cyclopentadienylchromium complex ( 7 ) were first synthesized, characterized, and tested as catalyst precursors for the olefin polymerization. In the presence of MAO, the complexes exhibited high catalytic activity for the polymerization of ethylene. It is shown that ligand variations can have a substantial effect on catalyst activity and stability. The effect of Al/Cr ratio on catalytic activity was also studied., Competing Interests: The authors declare no conflict of interest.

A series of titanium trichloride complexes , ligated with claw-type tetradentate aminophenolate ligands were synthesized from the direct reaction of TiCl4(THF)2 with 1 equiv. of the corresponding aminophenol in the presence of triethylamine. For comparison purposes, titanium isopropoxide complexes were also synthesized via the reaction of Ti(O(i)Pr)4 and 1 equiv. of the proligand. Similar reactions of ZrCl4(THF)2 with the corresponding aminophenol ligands in the presence of triethylamine only allowed the isolation of zirconium complex . The X-ray diffraction studies reveal that titanium trichloride complexes , and titanium triisopropoxide complex all possess a distorted octahedral geometry with the tetradentate aminophenolate ligand in cis-O, N, N chelating mode, where the methoxy group of the aryl unit does not coordinate with the metal center in the solid state. Upon activation with MMAO, these titanium and zirconium(iv) complexes exhibited moderate to high catalytic activities for ethylene polymerization at 30-120 °C, producing high-molecular-weight polyethylenes with broad distributions (Mw/Mn = 10.2-34.8). The activities of titanium trichloride complexes are significantly higher than those of titanium isopropoxide and zirconium trichloride complexes at high temperatures. The highest activity of 15 456 kg (mol-Ti h)(-1) could be achieved by titanium trichloride complex with bromo groups on both ortho- and para-positions of the phenolate ring of the ligand at 120 °C.