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Over metal catalysts, N‐heteroarenes, as one of the most versatile building blocks in pharmaceuticals, bioactive molecules and natural products, can be easily accessed by the oxidation of N‐heterocycles. Herein, we describe N‐doped hierarchical pore carbons (N‐HPCs) derived from readily available biomass (flour) efficiently catalyzed aerobic dehydrogenation of N‐heterocycles without any additives under mild conditions, owing to N dopant and high surface area indicated by characterization analysis. A wide range of N‐heteroarenes including quinolines, quinolinol, dihydroisoquinolines, isoquinolines, indoles, quinoxaline and acridine were obtained in good to excellent yields (36 examples, up to 99% yield). Mechanistic studies revealed a strikingly different non‐free radical process from metal catalysts, for which an apparent activation energy of 66.4 kJ mol−1 was found. Moreover, the N‐doped carbon exhibited robust stability and yielded 74.5% quinoline at the sixth reaction. The use of metal‐free catalysts in organic synthesis is attractive but practically challenging. This work provides a promising example for metal‐free catalysis. [ABSTRACT FROM AUTHOR]

Mesoporous carbon derived from natural vitamin B12 is applied for the first time in organic synthesis and exhibits exceptionally high dual activity for imine formation via the cross-coupling of alcohols with amines and the self-coupling of primary amines using molecular oxygen or air as the terminal oxidant. [ABSTRACT FROM AUTHOR]

Direct oxidation of 2,3-cyclopentenopyridine analogues to 6,7-dihydro-5H-cyclopenta[b]pyridin-5-one analogues was achieved using Mn(OTf)2 as a catalyst and t-BuOOH (65% in H2O) as an oxidant at 25 °C in H2O with high yield and excellent chemoselectivity for the first time. The catalytic system was also used efficiently for the direct oxidation of substituted benzylpyridines and 2-ethylpyridine in t-BuOH. [ABSTRACT FROM AUTHOR]

Novel PdVO x nanoparticles (NPs) prepared by a one-pot hydrogenation method are reported. X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, and UV/Vis spectroscopy were performed to characterize the PdVO x NPs. The NPs catalyzed benzene directly to phenol in 5.2 % yield with more than 99 % selectivity using O2 as the sole oxidant. [ABSTRACT FROM AUTHOR]

Abstract: Three organic–inorganic hybrid TM–Ln heterometallic phosphotungstates [Cu(dap)2(H2O)][Cu(dap)2]3.5[La(α-HPW11O39)2]·6H2O (1) [Cu(dap)2(H2O)]0.5[Cu(dap)2]4[Nd(α-HPW11O39)2]·4H2O (2) and [Cu(dap)2(H2O)]2[Cu(dap)2]3.5[Eu(α-PW11O39)2]·6H2O (3) (dap=1,2-diaminopropane) have been hydrothermally synthesized and structurally characterized by elemental analyses, IR spectra, optical diffuse reflectance spectra, powder X-ray diffraction (PXRD), thermogravimetric (TG) analyses and single-crystal X-ray diffraction. Their common features are that 1–3 all consist of asymmetric sandwich-type subunits [Ln(α-PW11O39)2]11− and [Cu(dap)2]2+ bridges. Both 1 and 2 display the 2-D (4,4)-topological sheets whereas 3 exhibits the 3-D 5-connected (46·64) topological framework. The magnetic properties of 2 and 3 and the luminescence performance of 3 have been measured. [Copyright &y& Elsevier]

Abstract: The hydrothermal reactions of Na8[A-α-HAsW9O34]·11H2O with CuCl2·2H2O, LnCl3 in the presence of ethylenediamine (en) lead to three novel 2D organic–inorganic hybrid CuII–LnIII heterometallic arsenotungstates Na3[Cu(en)2(H2O)][Cu(en)2]1.5[H3Ln(α-AsW11O39)2]·xH2O (Ln=DyIII, x =5 (1); Ln=GdIII, x =4 (2); Ln=LaIII, x =5.5 (3)), which have been characterized by elemental analyses, IR spectra, optical diffuse reflectance spectra, thermogravimetric analyses and single-crystal X-ray diffraction. 1–3 are isomorphic and exhibit the unique 2D honeycomb (6,3)-network topology constructed from sandwich-type [H3Ln(α-AsW11O39)2]8− units through [Cu(en)2]2+ linkers. To the best of our knowledge, 1–3 represent rare 2D organic–inorganic hybrid CuII–LnIII heterometallic arsenotungstates. The photocatalytic measurements show that 1–3 can to some extent inhibit the photodegradation of rhodamine-B. Moreover, magnetic measurements demonstrate that there are the weak ferromagnetic behaviors in 1 and 2. [Copyright &y& Elsevier]

A series of physical mixtures of Na4P2S6 and NiCl2 (P‐NiPS(x), where x represents the P/Ni molar ratio) were employed for the preparation of Ni2P. For comparison, a sulfur‐containing Ni2P catalyst (Ni2P‐S) and a sulfur‐free Ni2P catalyst (Ni2P‐TPR) were prepared by reduction of Ni2P2S6 and a nickel phosphate precursor, respectively. The reduction of the P‐NiPS(x) precursors with P/Ni ratios above 2/3 yielded Ni2P catalysts with a distinct nickel phosphosulfide layer (NiPS(x)), and the Ni2P phase started to form at ca. 200 °C. The reduction of Ni2P2S6 to Ni2P most likely follows a disproportionation mechanism. The P3+ species in Ni2P2S6 disproportionate to PH3 and P5+ during the reduction, and PH3 further reacts with nickel and sulfur species to form Ni2P and the surface nickel phosphosulfide layer. The sulfur atoms in the nickel phosphosulfide phase were in the form of S2−. The introduction of sulfur to Ni2P favored the hydrogenation pathway of the hydrodesulfurization (HDS) of dibenzothiophene (DBT), but hardly affected the direct desulfurization (DDS) pathway and inhibited the hydrogenation of biphenyl. The DDS pathway rate constants of DBT HDS over the Ni2P‐TPR and NiPS(x) catalysts were observed to increase linearly with the increase in their surface Ni atomic concentrations. [ABSTRACT FROM AUTHOR]