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A novel Fe3O4@SiO2‐Pr‐Thiosemicarbazide‐Cu(II) as a magnetically separable catalyst was synthesized and further confirmed by FT‐IR, TGA, XRD, FE‐SEM, EDX, ICP‐AES, TEM, VSM, and XPS analyses. The catalytic efficiency of Fe3O4@SiO2‐Pr‐Thiosemicarbazide‐Cu(II) was examined in the one‐pot environmentally friendly synthesis of 1,2,3‐triazoles by reacting terminal alkynes, alkyl halides, and sodium azide in ethanol at 55°C. The results revealed Fe3O4@SiO2‐Pr‐Thiosemicarbazide‐Cu(II) nano–sizedcatalyst is advantageous in terms of excellent activity, high stability, and easily recoverable in the synthesis of 1,2,3‐triazoles. The mechanistic study of Fe3O4@SiO2‐Pr‐Thiosemicarbazide‐Cu(II) catalyzed synthesis of 1,2,3‐triazole is also supported by DFT calculations. The significant advantages of this catalytic system are mild reaction conditions, easy work‐up procedure, magnetic separation, heterogeneity, an excellent yield of the product, and recyclability without a notable decrease of catalytic potency for six runs. Further, histotoxicological assessment of synthesized 1,2,3‐triazoles was done on the Indian major carp Labeo rohita. [ABSTRACT FROM AUTHOR]

A promising electrode for hydrogen evolution reaction (HER) has been prepared via a reduction process to form NiF2 nanorod arrays directly grown on a 3D nickel foam. We reveal NiF2@Ni nanorod arrays for a stable hydrogen evolution reaction (HER) application. The computational analysis for H2O, OH and H and experimentally in aqueous KOH endow considerable shift in Fermi levels for Ni (111) unlike for NiF2 (110) on account of an effective coalition of p-orbitals of fluorine and d-orbitals of Ni in NiF2, NiF2 under pinning the reduced overpotential of 172 mV at 10 mA cm−2 compared to Ni (242 mV) in same electrolyte. The electrocatalytic mechanism has been proposed using density functional theory (DFT) and is found in well accordance with the experimental findings of the present study. The preparation of self-grown porous nanostructured electrodes on the 3D nickel foam via a displacement reaction is possibly valuable for other metal halides for energy storage and conversion applications as these materials have inherently smaller overpotentials. [ABSTRACT FROM AUTHOR]

A direct metal-free approach for the synthesis of novel sulfenylated 2-aminothiazole and imidazothiazole derivatives at room temperature is reported via an in situ-generated electrophilic thiolating agent. The present protocol provides mild and selective access for the insertion of C–S bond functionalization with good yield. The mechanistic path was justified via density functional theory (DFT) calculations, which explore the role of the solvent in the reaction mechanism. [ABSTRACT FROM AUTHOR]

Natural products, natural product-inspired molecules and natural product derivatives have contributed around 79% to the new chemotherapies against the most complex, deadly disease, cancer. In this study, a series of novel isoxazoline derivatives of Goniodiol diacetate (fused bicyclic pyranone isoxazoline derivatives)- a natural product derivative, were synthesized with quantitative yield as a single regioisomer by 1,3 - dipolar cycloaddition reaction with different aldoximes. The regiospecific product formed was confirmed by NOESY study and single-crystal X-ray diffraction. The regiospecificity of the product formation was further explained by coefficients of selected atomic orbitals in frontier molecular orbitals and natural population analysis (NPA in eV) of dipolarophile and dipole by density functional theory studies. All the derivatives have demonstrated anti-cancer activity selectively in human breast cancer (MDA-MB-231), ovarian cancer (SKOV3), prostate cancer (PC-3) and colon cancer (HCT-15) cell lines with EC 50 < 10 μM. Additionally, Annexin V/PI assay and cell cycle analysis on selected potent compound 3 f exhibited tuned apoptotic response & necrosis compared to standard Vincristine and showed cell growth arrest at the S phase. [Display omitted] [ABSTRACT FROM AUTHOR]

Regioselective amination of polyhalogenated heteroarenes (especially pyrimidines) has extensive synthetic and commercial relevance for drug synthesis applications but is plagued by the lack of effective synthetic strategies. Herein, we report the Cu(II)/PTABS-promoted highly regioselective nucleophilic aromatic substitution (S N Ar) of polychlorinated pyrimidines assisted by DFT predictions of the bond dissociation energies of different C-Cl bonds. The unique reactivity of Cu(II)-PTABS has been attributed to the coordination/activation mechanism that has been known to operate in these reactions, but further insights into the catalytic species have also been provided.

A promising electrode for hydrogen evolution reaction (HER) has been prepared via a reduction process to form NiF2 nanorod arrays directly grown on a 3D nickel foam. We reveal NiF2@Ni nanorod arrays for a stable hydrogen evolution reaction (HER) application. The computational analysis for H2O, OH and H and experimentally in aqueous KOH endow considerable shift in Fermi levels for Ni (111) unlike for NiF2 (110) on account of an effective coalition of p-orbitals of fluorine and d-orbitals of Ni in NiF2, NiF2 under pinning the reduced overpotential of 172 mV at 10 mA cm-2 compared to Ni (242 mV) in same electrolyte. The electrocatalytic mechanism has been proposed using density functional theory (DFT) and is found in well accordance with the experimental findings of the present study. The preparation of self-grown porous nanostructured electrodes on the 3D nickel foam via a displacement reaction is possibly valuable for other metal halides for energy storage and conversion applications as these materials have inherently smaller overpotentials.

A electrode for energy storage cells is possible directly on Ni foam, using a simple reduction process to form NiF 2 nanorod arrays (NA). We demonstrate NiF 2 @Ni NA for a symmetric electrochemical supercapattery electrode. With an areal specific capacitance of 51 F cm -2 at 0.25 mA cm -2 current density and 94% cycling stability, a NiF 2 @Ni electrode can exhibit supercapattery behavior, a combination of supercapacitor and battery-like redox. The symmetric electrochemical supercapattery delivers 31 W h m -2 energy density and 797 W m -2 power density with 83% retention in a 1 M KOH electrolyte, constituting a step toward manufacturing a laboratory-scale energy storage device based on metal halides. Producing self-grown hierarchically porous nanostructured electrodes on three-dimensional metal foams by displacement reactions may be useful for other metal halides as electrodes for supercapacitors, supercapatteries, and lithium-ion batteries., Competing Interests: The authors declare no competing financial interest., (Copyright © 2020 American Chemical Society.)