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We disclose herein a Au(I)-catalyzed domino cyclization of 1,6-diynes incorporated with indole. This protocol enabled the diastereoselective buildup of indole-fused azabicyclo[3.3.1]nonanes from linear precursors. Density functional theory calculations showed that the reaction proceeded via an unprecedented cascade dearomatization/rearomatization/dearomatization process. Independent gradient model analysis revealed that a noncovalent attractive interaction between the distal alkyne and the Au/proximal complex was responsible for the chemoselectivity of the first spirocyclization step.

The 2-methoxyiminoacyl-mediated arylation of substituted phenylalanines has been examined. Selective monoarylation at the ortho position was achieved using pyridone ligands which decelerate the arylation process. Density functional theory (DFT) study of a continuous C-H arylation process that included the first and second arylation stage was performed. The computational result shows that the introduction of a pyridone ligand obviously disfavors the second arylation stage, which directly contributes to the selectivity between the mono/diarylated products. Furthermore, results of the kinetic isotope effect and a control experiment are agreed with DFT study.

A new copper/silver-co-mediated three-component bicyclization of benzene-linked 1,6-enynes with ICF2CO2Et with TMSN3 was reported, and used to produce a wide range of hitherto unreported difluorinated tetrahydroindeno[1,2-c]azepine-3,6-diones with moderate to good yields. The mechanistic pathway consists of radical-induced 1,6-addition–cyclization, oxidative addition, reductive elimination, nitrene insertion and N–O cleavage, resulting in continuous multiple bond-forming events including C–C and C–N bonds to build up a 6/5/7 tricyclic framework.

The detection of volatile amines has attracted great attention due to their high toxicity and widespread existence. Herein, we report a new example of a metal–organic framework (Co-MOF-1) for the discriminative detection of alkylamines. Co-MOF-1 that was assembled by Co(II), N3− and viologen-based ligand [H2L]Cl2 ([1,1′-bis(4-carboxylatobenzyl)-4,4′-bipyridinium] dichloride) is a 3D cationic pcu framework with 1D channels containing electron-deficient viologen units, exhibits typical electrochemical redox properties and photochromic properties, and is involved in the radical formation via photoinduced electron transfer from nitrate ions and carboxylate groups in the channels to viologen moieties. More importantly, Co-MOF-1 shows different color responses to different volatile amine vapors of different types and molecular sizes, which is attributed to the electron transfer from the amine to viologen. Moreover, the reason why Co-MOF-1 can detect amines distinguishably is the different sizes of the substituents of the amine molecules and the number of N–H bonds of the amine molecules. Furthermore, the portable test paper was successfully prepared and provided a convenient and discernible detection of volatile amine vapors by depositing Co-MOF-1 onto the filter paper, which can also be used as an erasable inkless printing medium.

Interfacial engineering is an efficient strategy to develop electrocatalysts with excellent performance. By using this strategy, a novel Fe-doped urchin-like Ni2P/Ni3S2 (NPZFNS@C/NF) heterostructure with metal–organic frameworks (MOFs) as the precursor in-suit grows on nickel foam (NF) with abundant hetero-interfaces and carbon-coating is successfully constructed. Owing to the existence of hetero-interfaces and carbon coating, the unique surface electronic structure and d-band center of NPZFNS@C/NF are also obtained. Benefiting from the regulation of electronic structure and d-band center, the NPZFNS@C/NF electrode exhibits extremely high activity for oxygen evolution reaction (OER) and high activity for hydrogen evolution reaction (HER), which shows a very low overpotential of 141 mV at the current density of 10 mA cm−2 for OER and 129 mV for HER respectively in alkaline electrolyte. Furthermore, it also exhibits a small overpotential of 1.5 V for overall water splitting with NPZFNS@C/NF as both anode and cathode, which is lower than most of non-noble metal-based bifunctional electrocatalysts reported. Density functional theory (DFT) results further confirm that the hetero-interface with carbon coating can further optimize Gibbs free energies for both OER and HER processes. This design and constructure strategy provides a new avenue for overall water splitting.

An aerobic oxidative cyanation for the synthesis of α-aminonitriles was reported. The formation of C(sp3)-CN bonds was achieved under a metal-free condition by utilizing azobis(isobutyronitrile) as a sole organic cyanide source with the combination of pivalic acid and sodium acetate as additives.

Electrocatalytic Nitrogen Reduction Reaction (ECNRR) is a promising alternative NH3 production method relative to Haber-Bosch process. However, the ECNRR still suffers from rather low NH3 yield and selectivity (Faradaic efficiency (FE)) due to the poor catalytic activity of catalysts. Herein, benefiting from interface engineering, FeNi2S4/NiS hetero-interface electrocatalysts with unique electronic structures are successfully constructed, which the optimized catalyst can enhance the adsorption of N2 molecules meanwhile inhibit H atoms adsorption. Significantly, the NH3 yield and FE of FNS/CC-2 are reached to 128.398±1.32 μg h−1 cm−2 and 28.64 ± 0.18% which are higher than most of non-noble metal-based NRR electrocatalysts in alkaline electrolyte reported. Detailed experimental investigation and DFT calculations reveal that the enhanced electrocatalytic performance and selectivity of FeNi2S4/NiS towards N2 are attributed to the changes of the D-band center and electronic structure of electrocatalyst surface. The construction strategy of this NRR electrocatalyst provides a new avenue on electrocatalytic research.

The direct di-ortho-arylation of substituted phenylalanines has been accomplished via methoxyiminoacyl (MIA)-mediated Pd-catalyzed C H functionalization. A diverse array of phenylalanine substrates is amenable to this protocol, providing di-ortho-arylated phenylalanine derivatives with good to high efficiency. Computational results revealed that a bimetallic interaction between Pd(IV)-Ag(I) was formed through the localized orbital, which obviously favored the reductive elimination step of the arylation process.

Metal-organic frameworks (MOFs) have emerged as a promising electrode material for supercapacitors owing to their high porosity and a regular porous structure, however, the capacitance performance and/or ion conduction rate performance of most MOFs with poor electrical conductivity are greatly hindered. To increase the bulk electrical conductivity and the efficiency of MOFs, an effective method was proposed by interweaving organic conductive polymer polyaniline (PANI) and MOF crystals (ZIF-67) grown in situ. As a result, the highly conductive PANI that interlink the MOF particles (denoted as ZIF-67@PANI) increase the electron transfer between MOF particles while the effective porosity of the MOF is maintained, which greatly improves the electrical conductivity and capacitance of MOFs. Electrochemical studies indicates that the ZIF-67@PANI exhibits ultrahigh specific capacity of 1123.65 C g−1 at a current density of 1 A g−1 in a three-electrode system, superior rate capability (648.9 C g−1 at 10 A g−1 current density) and excellent cycling stability (92.3% capacity retention after 9000 cycles). Furthermore, a symmetrical supercapacitor device based on ZIF-67@PANI network exhibits ultrahigh energy density of 71.1 W h kg−1 at a power density of 504.72 W kg−1 at 1 A g−1 current density. The capacitance performance of ZIF-67@PANI-2 we report here is the best among the supercapacitor materials formed by MOFs and conductive polymers up to date, confirming the importance of hybrid materials on the nanoscale and the significance of in situ synthetic chemistry.

A new three-dimensional Eu(III) metal–organic framework Eu(III)-MOF-1 formulated as [Eu3(BDC)4.5(H2O)(DMF)2] (H2BDC = 1,4-benzenedicarboxylic acid), has been successfully synthesized by solvothermal methods and characterized by structural analyses and luminescence studies. Crystallographic studies reveal that the Eu-MOF-1 exhibits an unusual 3D framework based on 1D metal-carboxylate chains. Significantly, the luminescence explorations demonstrate that the Eu-MOF-1 is the first multi-responsive fluorescence sensor for sensing biomarker 1-naphthol (1-N) of carbaryl exposure, Fe3+ ions and MnO4− ions with high sensitivity, selectivity and excellent recyclability through luminescence quenching. Moreover, the possible mechanisms of selective detection have been investigated in detail. This material could be a promising luminescent sensor for practical applications.