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The reaction of arylaldehydes and arylamines with nontoxic NH4SCN in the presence of TBHP led to a divergent Strecker synthesis of aminonitriles and iminonitriles.

Here we report an Ag-modified Cu/CuO (Cu/CuO–Ag) catalyst with a porous 3D structure, which can efficiently electrochemically reduce CO2 to ethylene and other C2+ products.

A metal-free divergent synthesis of indoles dependent on reagents was described. The reaction of 2-vinylanilines with DMSO/SOCl2 was found to give 2-thiomethylindoles, while replacing DMSO with diethyl sulfoxide afforded 2-unsubstituted indoles.

The reaction of N-arylpropynamides with (dichloroiodo)benzene (PhICl2) and diselenides/disulfides resulted in a divergent synthesis of chalcogenylated quinolinones and spiro[4.5]trienes through intramolecular electrophilic cyclization and chalcogenylation. The chalcogenyl functional group was introduced by an electrophilic reactive organosulfenyl chloride or selenenyl chloride species, generated in situ from the reaction of disulfides/diselenides and PhICl2. Notably, the divergent cyclization pathways were determined by the substituent type on the aniline ring in N-arylpropynamide substrates. Substrates bearing a fluoro, methoxy or trifluoromethoxy group at the para-position of the aniline underwent an alternative spiralization pathway to give the 3-chalcogenylated spiro[4,5]trienones.

In the past several decades, hypervalent iodine chemistry has witnessed prosperous development as hypervalent iodine reagents have been widely used in various organic transformations. Specifically, hypervalent iodine reagents have been vastly used in various bondforming reactions. Among these oxidative coupling reactions, the reactions involving the formation of C-N bond have been extensively explored to construct various heterocyclic skeletons and synthesize various useful building blocks. This review article is to summarize all the transformations in which carbon-nitrogen bond formation occurred by using hypervalent iodine reagents under metal-free conditions.

The reaction of 2-alkenylanilines with SOCl2 in DMSO was found to selectively afford 3-unsubstituted indoles and 3-methylthioindoles. This switchable approach was found to be temperature-dependent: at room temperature, the reaction afforded 3-unsubstituted indoles through intramolecular cyclization and elimination; while at higher temperature, the reaction gave 3-methylthioindoles via further electrophilic methylthiolation.

During the past several decades, hypervalent iodine reagents have been widely used in various organic transformations. Specifically, these exclusive classes of reagents have been extensively used for the construction of carbon-carbon bonds. This review aims to cover all the reactions involving the construction of carbon-carbon bonds mediated by hypervalent iodine reagents, providing references and highlights for synthetic chemists who are interested in hypervalent iodine chemistry.

Bimetallic catalysts have been widely used for CO methanation because of their superior activity and stability. Herein, Ni–Co bimetallic catalysts supported on SiO2, xNi–yCo/SiO2 (x and y refer to ...

Ni/SiO2 catalysts are prepared via plasma-induced micro-combustion method in this study. The process during micro-combustion is analyzed and the catalysts are applied for syngas methanation. Discrete combustion is observed in the process of plasma-induced micro-combustion. X-ray diffraction, Temperature programmed reduction together with X-ray photoelectron spectroscopy disclose that highly dispersed NiO strongly interacting with SiO2 generates when prepared via micro-combustion method. X-ray diffraction and transmission electron microscope verifies the smaller metal Ni particles after reduction. Thus, NiO aggregation is prevent and strong interaction between NiO and SiO2 restrained metal Ni sintering during reduction via moderate micro-combustion. The as-prepared Ni catalysts also own higher surface areas, higher pore volumes and pore diameters. These characters prominently enhance the activity and stability of catalysts in syngas methanation. This work provides a promising method to synthesize nanoscale materials.

A highly substituent-dependent rearrangement allows for the novel and SOCl2-induced divergent synthesis of 3-methylthioquinolin-2-ones and 3-methylthiospiro[4.5]trienones through intramolecular electrophilic cyclization of N-aryl propyamides. DMSO acts as both solvent and sulfur source, and use of DMSO-h6/d6 enables the incorporation of SCH3 or SCD3 moieties to the 3-position of the heterocyclic framework. Different para-substituents trigger divergent reaction pathways leading to the formation of quinolin-2-ones for mild substituents and spiro[4,5]trienones for both electron-withdrawing and -donating substituents, respectively. On the basis of both computational and experimental results, a new mechanism has been put forward that accounts for the exclusive spirolization/defluorination process and the surprising substituent effects.

The reaction of 2-alkenylanilines with SOCl2 in DMSO was found to selectively afford 3-unsubstituted indoles and 3-methylthioindoles. This switchable approach was found to be temperature-dependent: at room temperature, the reaction afforded 3-unsubstituted indoles through intramolecular cyclization and elimination; while at higher temperature, the reaction gave 3-methylthioindoles via further electrophilic methylthiolation.

A highly substituent-dependent rearrangement allows for the novel and SOCl2-induced divergent synthesis of 3-methylthioquinolin-2-ones and 3-methylthiospiro[4.5]trienones through intramolecular electrophilic cyclization of N-aryl propyamides. DMSO acts as both solvent and sulfur source, and use of DMSO-h6/d6 enables the incorporation of SCH3 or SCD3 moieties to the 3-position of the heterocyclic framework. Different para-substituents trigger divergent reaction pathways leading to the formation of quinolin-2-ones for mild substituents and spiro[4,5]trienones for both electron-withdrawing and -donating substituents, respectively. On the basis of both computational and experimental results, a new mechanism has been put forward that accounts for the exclusive spirolization/defluorination process and the surprising substituent effects.

The application of silicon-based anode remains a serious challenge due to its intrinsic volumetric expansion effect and low conductivity. In our work, a novel CNT-interspersed hierarchical carbon shell structure (denoted as PDA@CoZn-NC@Si) is synthesized by wrapping Si uniformly in the bimetallic zeolite imidazolate frameworks (ZIFs) and then encapsulated with a dopamine-derived carbon shell. The PDA@CoZn-NC@Si anode delivers better cycle stability of 814 mAh/g at 0.5C for 400 cycles (only −0.14% capacity reduction per cycle) and possesses excellent rate capability, which benefits from the inner porous buffer spaces, interspersed CNT, and solid heterogeneous carbon shells. In addition, the full cell is assembled by pairing a solution-based chemically prelithiated PDA@CoZn-NC@Si anode with a Li(Ni1/3Co1/3Mn1/3)O2 (NCM111) cathode, and it presents an improved initial coulombic efficiency (88.3%) and a high energy density (419.8 Wh/kg). This study provides effective guidance for optimizing the microstructure design and prelithium of Si-based anodes.

It is highly important to develop high-performance sulfur cathode to solve low areal sulfur loading, shuttling and sluggish conversion of polysulfides for lithium-sulfur batteries. Herein, a three-dimensional (3D) freestanding framework configured with Co nanoparticles and Co-Nx codoped carbon nanotubes anchored in a carbon foam is synthesized and investigated as a new type of sulfur host. Such an architecture can serve not only as a conductive carbon networks but also as host scaffold for high sulfur-containing electrodes. The hierarchical porous structures cooperated with high density and dispersion multifunctional Co-Nx species can efficiently trap and manipulate catalytic conversion kinetics of polysulfides. Benefiting from above characteristics, the designed cathodes exhibit a high capacity (1259 mA h g−1) at 0.1 C and excellent cycling performance with an ultralow decay of 0.038% per cycle over 500 cycles at a high current density of 3 C. Even with a high sulfur loading (7.0 mg cm−2) and lean electrolyte (E/S = 5 μL mg−1) operation, a high areal capacity of 4.34 mA h cm−2 is still achieved after 100 cycles at 0.1 C. This work provides a low-cost route for preparation of freestanding cathode materials toward highly efficient lithium-sulfur batteries.

Designing and tailoring the fine structure of bimetallic nanoparticles is an essential and effective way to boost the catalytic properties. Herein, two types of Ni-Co alloys are generated on SiO2 including non-homogeneous or homogeneous form for CO methanation. The formation of homogeneous Ni-Co alloy originates from the strong interaction between Ni and Co and a small amount of CoO. Compared with non-homogeneous alloy, the homogeneous Ni-Co alloy exhibits superior CO conversion and CH4 selectivity below 380 °C, and is stable for 100 h long-term test at 400 °C in CO methanation. The electron enrichment of Ni and Co of homogeneous alloy contributes to CO dissociation, hydrogen spillover, and CO2 adsorption, which facilitates CH4 formation and the removal of deposited carbon species. This work provides a new clue for fabricating bimetallic catalysts and revealing the relationship between the fine structure of Ni-Co alloy and their catalytic performances.

In this work, flowerlike NiO is successfully prepared via a facile homogeneous precipitation method using different surfactants as templates in water/ethanol solution. And the flowerlike NiO using sodium dodecyl sulfate as surfactant possesses larger specific surface area (188.3 m2/g) and better electrochemical performance. The electrochemical property of NiO is further optimized through changing the ratios of water and ethanol and the material delivers high specific capacitance (631.7 F/g at 1 A/g) and excellent durability (82.8% capacitance retention after 5000 cycles at 10 A/g) when the ratio of water/ethanol is 3:1. The characterizations confirm that the outstanding performance of this material derives from the petal-particle cross-linking flowerlike structure of NiO. The possible formation mechanism is proposed. This work provides a novel method for preparing NiO electrode material with high performance supercapacitor.