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Constructing a C–N bond by merging electrochemistry and nickel catalysis is considered a powerful strategy. Herein, we investigate highly efficient intramolecular amination at room temperature with excellent functional group tolerance. Mechanistic studies suggest that the rapid ligand exchange may lead to the NiI/NiIIIcatalytic cycle. This method not only provides a new perspective for intramolecular amination but also offers a novel approach for constructing the benzothiazine scaffold.

The merger of electrochemistry and transition metal catalysis has emerged as a powerful tool to join two electrophiles in an enantioselective manner. However, the development of enantioselective electroreductive cross-couplings of olefins remains a challenge. Inspired by the advantages of the synergistic use of electrochemistry with nickel catalysis, we present here a Ni-catalyzed enantioselective electroreductive cross-coupling of acrylates with aryl halides and alkyl bromides, which affords chiral α-aryl carbonyls in good to excellent enantioselectivity. Additionally, this catalytic reaction can be applied to (hetero)aryl chlorides, which is difficult to achieve by other methods. The combination of cyclic voltammetry analysis with electrode potential studies suggests that the NiIspecies activates aryl halides by oxidative addition and alkyl bromides by single-electron transfer.

Electrochemistry-enabled rhodium-catalyzed C–H amination and amination cyclization of arene assisted by a weakly coordinating amide have been reported. Additionally, aryl amines and dihydroquinazolinones could be obtained selectively by controlling the electric current. Mechanistic studies suggested that the amination reaction likely involves an electrochemical oxidation-induced reductive elimination of a high valent rhodium intermediate, which led to the amination reaction even proceeding smoothly at room temperature.

A method for the C(sp3)–H alkenylation of N-aryl-tetrahydroisoquinoline (THIQ) has been developed by the combination of electrooxidation and a copper catalyst. The corresponding products were obtained with good to excellent yields under mild conditions. Besides, the addition of TEMPO as an electron mediator is crucial to this transformation, since the oxidative reaction could proceed under a low electrode potential. In addition, the catalytic asymmetric variant has also been demonstrated with good enantioselectivity.

C(sp3)–H alkenylation of tetrahydroisoquinoline by merging Shono oxidation and the Morita–Baylis–Hillman reaction is developed, employing 4-dimethylaminopyridine as an organocatalyst and TEMPO/NaBr as an electrocatalyst. The reaction proceeds via the interception of an iminium cation intermediate, which is generated in situ from anodic oxidation, leading to aza-Morita–Baylis–Hillman reaction products. Additionally, the use of TEMPO and NaBr as mediators is crucial to avoid the decomposition of products by lowering the oxidation potential of the reaction.

Process intensification equipment is playing an increasingly role in the emulsion process. A novel rotating solid foam stirrer tank (RSFST) is developed in this work to try to intensify the liquid–liquid emulsification process. The effects of operating parameters and physical parameters, such as emulsification time, rotational speed, packing size, dispersed phase volume fraction, and continuous-phase viscosity, on the droplet size distribution and Sauter mean diameter d32of oil-in-water emulsions produced in RSFST were investigated using a kerosene–water system. To benchmark the emulsion performance of the RSFST, a Rushton stirrer is used a reference stirrer and the generated droplet size and average energy dissipation rate as the evaluation metrics. Based on the experimental data of emulsification under different operating conditions and physical parameters, models are applied to describe the bimodal distribution of oil-in-water emulsion droplet sizes, and correlation is proposed to predict the Sauter mean diameter d32of RSFST. This work provides fundamental data for practical applications of RSFST used in emulsion process intensification.

Electrochemistry has been successfully applied in metal catalysis to avoid the usage of chemical redox agents. This strategy proved to be a powerful approach to construct carbon–carbon (C–C) and carbon–heteroatom (C–X) bonds. However, most of the developed methods are based on either anodic oxidation or cathodic reduction, in which a sacrificial reaction occurs at the counter electrode. Paired electrolysis merging with metal catalysis is underdeveloped, wherein both anodic and cathodic processes are taking place simultaneously. Herein, we demonstrated that by using esterification of carboxylic acids with aryl halides via paired electrolysis using nickel as the catalyst the respective aryl esters were obtained in good to excellent yields at room temperature in an undivided electrochemical cell.

Electrochemically driven, Cp*Ir(III)-catalyzed regioselective annulative couplings of benzoic acids with alkynes have been established herein. The combination of iridium catalyst and electricity not only circumvents the need for stoichiometric amount of chemical oxidant, but also ensures broad reaction compatibility with a wide array of sterically and electronically diverse substrates. This electrochemical approach represents a sustainable strategy as an ideal alternative and supplement to the oxidative annulations methodology to be engaged in the synthesis of isocoumarin derivatives.

Phthalocyanine, as an organic dye, has attracted much attention due to its high molar absorption coefficient in the near-infrared region (NIR). It is precisely because of this advantage that phthalocyanine is very beneficial to photoacoustic imaging (PAI). At present, many different strategies have been adopted to design phthalocyanine-based contrast agents with photoacoustic (PA) effect, including increasing water solubility, changing spectral properties, prolonging the circulation time, constructing activatable supramolecular nanoparticles, increasing targeting, etc.Based on this, this minireview highlighted the above ways to enhance the PA effect of phthalocyanine. What's more, the application of phthalocyanine-based PA contrast agents in biomedical imaging and image-guided phototherapy has been discussed. Finally, this minireview also provides the prospects and challenges of phthalocyanine-based PA contrast agents in order to provide some reference for the application of phthalocyanine-based PA contrast agents in biomedical imaging and guiding tumor treatment.

A scalable enantioselective nickel-catalyzed electrochemical reductive homocoupling of aryl bromides has been developed, affording enantioenriched axially chiral biaryls in good yield under mild conditions using electricity as a reductant in an undivided cell. Common metal reductants such as Mn or Zn powder resulted in significantly lower yields in the absence of electric current under otherwise identical conditions, underscoring the enhanced reactivity provided by the combination of transition metal catalysis and electrochemistry.

A simple and mild protocol for copper-catalyzed bromination of quinoline at the C5 site of quinoline by anodic oxidation was developed, affording the desired remote C–H activation products with isolated yields of up to about 90%. The reaction proceeds with low-cost NH4Br and shows mild and green conditions (electricity as a green oxidant; NH3and H2as byproducts). At the same time, a gram-scale bromination reaction was also successfully fulfilled, showing its potential applicable value in organic synthesis. Moreover, the CV chart further demonstrated the proposed catalytic cycle.

Electrochemical synthesis of organic compounds has emerged as an attractive and environmentally benign alternative to conventional approaches for oxidation and reduction of organic compounds that utilizes electric current instead of chemical oxidants and reductants. As such, many useful transformations have been developed, including the Kolbe reaction, the Simons fluorination process, the Monsanto adiponitrile process, and the Shono oxidation, to name a few. Electrochemical C–H functionalization represents one of the most promising reaction types among many electrochemical transformations, since this process avoids prefunctionalization of substrates and provides novel retrosynthetic disconnections. However, site-selective anodic oxidation of C–H bonds is still a fundamental challenge due to the high oxidation potentials of C–H bonds compared to organic solvents and common functional groups. To overcome this issue, indirect electrolysis via the action of a mediator (a redox catalyst) is regularly employed, by which the selectivity can be controlled following reaction of said mediator with the substrate. Since the redox potentials of transition metal complexes can be easily tuned by modification of the ligand, the synergistic use of electrochemistry and transition metal catalysis to achieve site-selective C–H functionalization is an attractive strategy.

This paper presents a comparative study on the motions of a ship advancing in waves using two different three-dimensional time domain boundary element methods: a Transient Free surface Green's Function (TFGF) method and a Rankine Higher Order Boundary Element Method (HOBEM). Three models based on the HOBEM are also considered to identify the dominant factors affecting the accuracy of solutions: (i) the N–K model using Neumann–Kelvin (N–K) linearization, (ii) the N–K+DB model using the N–K linearization for the free surface boundary conditions and the double-body (DB) m -terms in the body boundary condition, (iii) the Rankine HOBEM based on DB linearization. The Wigley I and the Series 60 (C B = =0.7) are taken as study objects. The comparisons show that the Rankine HOBEM based on DB linearization is generally more accurate than the Rankine HOBEM with other two models and the TFGF method. The hydrodynamic coefficients are mainly affected by the m -terms, especially at low frequencies; while the influences of different linearizations of the free surface boundary conditions are negligible. Both the m -terms and the leading terms of steady velocity potential reserved in the free surface boundary conditions are important for motion responses, while the influence of the former is stronger than the latter. [ABSTRACT FROM AUTHOR]

Synergistic use of electrochemistry and organometallic catalysis has emerged as a powerful tool for site-selective C–H functionalization, yet this type of transformation has thus far mainly been limited to arene C–H functionalization. Herein, we report the development of electrochemical vinylic C–H functionalization of acrylic acids with alkynes. In this reaction an iridium catalyst enables C–H/O–H functionalization for alkyne annulation, affording α-pyrones with good to excellent yields in an undivided cell. Preliminary mechanistic studies show that anodic oxidation is crucial for releasing the product and regeneration of an Ir(III) intermediate from a diene-Ir(I) complex, which is a coordinatively saturated, 18-electron complex. Importantly, common chemical oxidants such as Ag(I) or Cu(II) did not give significant amounts of the desired product in the absence of electrical current under otherwise identical conditions.

Given the versatility and value of the structurally diverse organohalides and CF3-containing compounds in organic synthesis, we reported a green, oxidant-free electrochemical method using undivided electrochemical cells for radical bromination, chlorination and trifluoromethylation–formyloxylation of the various alkenes with readily available halogen radical (NaCl, NaBr), trifluoromethyl radical (CF3SO2Na) sources, and DMF as formyloxylation reagents. The protocol is operationally simple and robust and the Cl–, Br–or CF3–was directly oxidized at the anode, obviating the need for exogenous chemical oxidants.

The palladium-catalyzed electrochemical C–H bromination of benzamide derivatives under divided cells is developed, in which NH4Br serves as a brominating reagent and electrolyte. The protocol avoids the use of chemical oxidants and provides an alternative method for the synthesis of aryl bromides.

The development of efficient and practical methods to construct carboxylic acids using CO2as a C1 synthon is of great importance. Nickel-catalyzed carboxylation of aryl fluorosulfates and heteroaryl fluorosulfates with CO2is described, affording arene carboxylic acids with good to excellent yields under mild conditions. In addition, a one-pot phenol fluorosulfation/carboxylation is developed.

Palladium-catalyzed electrochemical C–H functionalization reactions have emerged as attractive tools for organic synthesis. This process offers an alternative to conventional methods that require harsh chemical oxidants. However, this electrolysis requires divided cells to avoid catalyst deactivation by cathodic reduction. Herein, we report the first example of palladium-catalyzed electrochemical C–H alkylation of arenes using undivided electrochemical cells in water, thereby providing a practical solution for the introduction of alkyl groups into arenes.

We have developed a Ni-catalyzed enantioselective hydroarylation of styrenes with arylboronic acids using MeOH as the hydrogen source, providing an efficient method to access 1,1-diarylalkanes, which are essential structural units in many biologically active compounds. In addition, Ni-catalyzed enantioselective hydrovinylation of styrenes with vinylboronic acids is also realized with good yields and enantioselectivities. The synthetic utility was demonstrated by the efficient synthesis of (R)-(−)-ibuprofen.

Palladium-catalyzed transfer semihydrogenation of alkynes using H2O as the hydrogen source and Mn as the reducing reagent is developed, affording cis- and trans-alkenes selectively under mild conditions. In addition, this method provides an efficient way to access various cis-1,2-dideuterioalkenes and trans-1,2-dideuterioalkenes by using D2O instead of H2O.

Electrochemical oxidation represents an environmentally friendly solution to conventional methods that require caustic stoichiometric chemical oxidants. However, C–H functionalizations merging transition-metal catalysis and electrochemical techniques are, to date, largely confined to the use of precious metals and divided cells. Herein, we report the first examples of copper-catalyzed electrochemical C–H aminations of arenes at room temperature using undivided electrochemical cells, thereby providing a practical solution for the construction of arylamines. The use of n-Bu4NI as a redox mediator is crucial for this transformation. On the basis of mechanistic studies including kinetic profiles, isotope effects, cyclic voltammetric analyses, and radical inhibition experiments, the reaction appears to proceed via a single-electron-transfer (SET) process, and a high valent Cu(III) species is likely involved. These findings provide a new avenue for transition-metal-catalyzed electrochemical C–H functionalization reactions using redox mediators.

Information highway with computer network technology as the core, its rise and development, make the function of information system and the connotation constantly development and improvement, for the future information society provides an efficient, fast, and even intelligent work environment. In view of the defects of petroleum in engineering cost management, it put forward the " design of petroleum engineering cost management system based on B/S architecture ", by this scheme can improve the efficiency of existing petroleum engineering cost management, cost management for oil development has great benefits.

With the speeding up of economic globalization, the survival and development of enterprise faces unprecedented pressure. The maturing information technology creates conditions for enterprises to improve management level. ERP system which integrates the enterprise management, business process, basic data, manpower material resources, computer hardware and software resources, is the product of enterprise management thought and advanced information technology, providing a strong incentive for enterprise operation and development. This paper analyzes the characteristics of the Chinese enterprises in the process of implementing ERP system, and the ERP system in the different stages of enterprise applications is studied, build methodology for a reference model of ERP rapid implementation based on enterprise.

Along with the development of petroleum enterprise information application system, the system of internal structure is increasingly complex. Oil companies involved in oilfield exploration and development data resources, management and operation of all aspects of each application level, is a complicated system engineering. To do well in the construction of data resources, it must be based on oil field exploration and development of process and production of the practical need of field management, comprehensive business operation each link of original data, makes the oil field enterprises gradually activate various data assets, the height of the realization of information sharing. And the data resources integration, mining, into a reliable and useful information, so that the leadership decision-making.

In the process of oil production equipment operation parameters and running status, it is receiving sensor monitoring analysis and provides the central control room. These through the data from the sensing device are oil production equipment data, it is real time acquisition and storage of remote transmission, to realize the quick production situation and the importance of conducting scientific real-time decision-making basis. In order to realize the data acquisition of remote transmission application, meet the long-distance monitoring and management of production equipment, data management system needs to research and develop the production equipment data management system.

Oil production equipment has a large amount of information, data acquisition channels, strong professional characteristics, and the data real-time, reliability and consistency of the demand is higher. For the production department for oil real-time data and collect data source point each production run for unified management, timely and accurate response oil production information, to improve the efficiency of collaborative work between the production departments, it provides a full range of production equipment management information service and aided decision basis. This paper from the aspects of system requirements and system architecture of oil production equipment running information integration platform has carried on the overall analysis and design.

Due to the city indoor substations have caused serious noise pollution to the environment. Appling the software VA One based on statistical energy analysis method, a compatible model has been established to simulate the sound field at the main transformer chamber of a substation indoor and outdoor. Compared the results of simulation and experiment, the validity of the model is confirmed. Consequently, the subsystems partition method and the noise exposure forecast method are proposed based on the results. Giving a reference to analyze similar models.

Die reduktive Eliminierung teils oder vollständig oxidierter Metallzentren ist ein wichtiger Schritt in einer Unzahl von C‐C‐ und C‐Heteroatom‐Bindungsbildungen. Eine Möglichkeit, anspruchsvolle reduktive Eliminierungen zu erleichtern, besteht in der Oxidation der Metallzentren durch Zwei‐Elektronen‐Oxidationsmittel (also von Mnzu Mn+2). Viele der für diese Umwandlung typischen Oxidationsmittel enthalten allerdings Sauerstoff‐, Stickstoff‐ oder Halogenatome — die sich anschließend an der reduktiven Eliminierung beteiligen könnten —, sodass ein Produktgemisch entstehen würde. In diesem Kurzaufsatz beschreiben wir die Untersuchungen zu einem neuartigen Lösungsansatz für dieses verbreitete Problem in der metallorganischen Chemie: die Verwendung von passiven F+‐Oxidationsmitteln sowie die jüngsten Anwendungen in PdII/PdIV‐ und AuI/AuIII‐Katalysen. Außerdem besprechen wir kurz ein seltenes Beispiel, in dem die Verwendung eines Ein‐Elektronen‐Oxidationsmittels zur Begünstigung einer selektiven reduktiven Eliminierung bei Palladium(II)‐katalysierten C‐H‐Funktionalisierungen gezeigt werden konnte; dies sehen wir als eine vielversprechende Richtung für zukünftige Anwendungen auf diesem Gebiet an.

Reductive elimination from partially or completely oxidized metal centers is a vital step in a myriad of carbon–carbon and carbon–heteroatom bond‐forming reactions. One strategy for promoting otherwise challenging reductive elimination reactions is to oxidize the metal center using a two‐electron oxidant (that is, from M(n)to M(n+2)). However, many of the commonly used oxidants for this type of transformation contain oxygen, nitrogen, or halogen moieties that are subsequently capable of participating in reductive elimination, thus leading to a mixture of products. In this Minireview, we examine the use of bystanding F+oxidants for addressing this widespread problem in organometallic chemistry and describe recent applications in PdII/PdIVand AuI/AuIIIcatalysis. We then briefly discuss a rare example in which one‐electron oxidants have been shown to promote selective reductive elimination in palladium(II)‐catalyzed CH functionalization, which we view as a promising future direction in the field.

The fabrication processing, dielectric properties and thermal properties of polymer-matrix composites containing AlN particles (10μm) for electronic substrates and microelectronic packaging applications were investigated. The epoxy resin (E-51) is used as the matrix, and the dispersion of the AlN in the composites is varied form 0 vol% to 40 vol%. The microstructures of the polymer-matrix composites are observed through scanning electron microscopy (SEM). With increasing the AlN content, thermal conducting of composites is improved, while the composites still keep the relatively low dielectric constant and dielectric loss. According to the dielectric properties dependence on frequencies (1kHz-10MHz) of the composites, the Cole-Cole plot is analyzed. The dipole relaxation in the composite is induced, and it is suggested that the air layer exit between the epoxy resin and the AlN particles.

Mono-dispersed silver nanoparticles with various morphologies were synthesized in large quantities by reducing silver nitrate with ethylene glycol in the presence of poly(vinylpyrrolidone) (PVP). The effects of the concentration of AgNO3, temperature, adding rates of PVP and AgNO3 injected into ethylene glycol as well as molar ratio between the repeating unit of PVP and AgNO3 were discussed. By varying the temperature and reaction time, silver nanocubes, n[removed info]noprisms and nanospheres were obtained. It is indicated that at elevated temperatures, the ethylene glycol can reduce Ag+ ion into Ag atoms, and thereby inducing the nucleation and growth of silver nanostructures in the solution phase. In the polymer-mediated polyol process, PVP plays a critical role in producing silver nanostructures with good stability and size/shape uniformity. As a result, both the crystallinity of a seed and extent of PVP coverage on the seed were instrumental in controlling the morphology of Ag nanoparticles.

An electrochemical asymmetric coupling of secondary acyclic amines with ketones via a Shono-type oxidation has been described, affording the corresponding amino acid derivatives with good to excellent diastereoselectivity and enantioselectivity. The addition of an N-oxyl radical as a redox mediator could selectively oxidize the substrate rather than the product, although their oxidation potential difference is subtle (about 13 mV). This electrochemical transformation proceeds in the absence of stoichiometric additives, including metals, oxidants, and electrolytes, which gives it good functional group compatibility. Mechanistic studies suggest that proton-mediated racemization of the product is prevented by the reduction of protons at the cathode.

A novel protocol to effect monoselective C—H amination on a broad range of benzamide substrates with electrophilic O‐benzoyl hydroxylamines is described.

Review: ca. 100 refs.

A new protocol is applied to various triflamide substrates tolerating a broad spectrum of functional groups.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.