122 results about "Electronic effect" patented technology

The invention belongs to the technical field of organic synthesis, and particularly discloses an ammonia aromatic alkene modified near-infrared BODIPY fluorescent probe as well as a preparation method and application thereof.The near-infrared BODIPY fluorescent probe is obtained by adopting 6-(dimethylamino) nicotinic aldehyde to directionally modify the alpha position of BODIPY and constructing an expanded conjugated system through Knoevenagel condensation. Wherein dimethylamino provides a strong electron donating effect, a molecular structure is twisted into a non-planar configuration due to steric hindrance of a pyridine ring, pi-pi accumulation is reduced, and an ACQ effect is inhibited. According to the structural modification strategy, significant red shift of absorption / emission wavelength is realized by expanding a molecular pi-conjugated skeleton, and meanwhile, the stability of the BODIPY core and the quantum yield are effectively enhanced. The probe molecule can specifically recognize the diphenylalanine dipeptide structural unit by utilizing the synergistic coordination effect of the 2-aminopyridine derivative and the BODIPY mother nucleus, so that the selective detection of the Alzheimer's disease biomarker Abeta42 is realized, and a novel optical detection tool is provided for the early molecular diagnosis and targeted therapy of AD (Alzheimer's disease).

The invention relates to the technical field of catalysts, in particular to an alkaline electrolytic water hydrogen evolution catalyst of a Pt-Co core-shell nanocluster loaded VN / CNT composite carrier, which comprises a composite carrier and a core-shell nanocluster loaded on the composite carrier, the composite carrier is a VN / CNT composite carrier, and the core-shell nano-cluster is a Pt-Co core-shell nano-cluster; the Pt-Co core-shell nano-cluster takes Pt as a core and Co as a shell, and the particle size of the core-shell is 1-15 nm; the VN / CNT composite carrier comprises CNT and VN nanoparticles loaded on the CNT, and the mass fraction of VN is 5%-40%. In the Pt-Co core-shell structure, the Co shell layer optimizes the d band center of Pt through an electronic effect, and reduces the adsorption energy barrier of H *; meanwhile, the Co shell serves as a co-catalyst, dissociation of H2O under the alkaline condition is remarkably promoted, and compared with a single Pt catalyst, the activity is improved by 30% or above under the same Pt dosage.

The invention discloses a preparation method and application of a TiO2 / Ag-coated MoS2 composite photocatalyst, and relates to the technical field of catalysts.The method comprises the steps that titanium dioxide is evenly dispersed in an ethanol-water mixed solution to form turbid liquid; adding a silver nitrate solution and carrying out ultraviolet irradiation to carry out a photodeposition process; adding an ammonium tetrathiomolybdate precursor solution into the turbid liquid, carrying out ultraviolet irradiation, inducing MoS < 2-> to be subjected to an auto-oxidation reduction reaction through an electronic effect, generating an amorphous MoS2 shell on the surface of silver, and forming a core-shell Ag-coated MoS2 cocatalyst; and centrifuging, washing and drying to obtain the TiO2 / Ag-coated MoS2 composite photocatalyst. According to the Ag-coated MoS2 cocatalyst, the electron density of S atoms is higher, the strength of S (2 + delta)-Had bonds is weakened, and Had is more easily desorbed to form hydrogen; and the photocatalyst also has better light absorption and photo-generated charge separation efficiency, so that the photocatalyst shows better photocatalytic hydrogen evolution activity and stability.

The invention discloses a method for purifying water by catalyzing ozonation through a nitrogen-fluorine co-doped carbon-loaded cobalt nanomaterial. Co-ZIF-8 and polytetrafluoroethylene (PTFE) are respectively used as a precursor and a fluorine source, and the nitrogen-fluorine co-doped carbon-loaded cobalt nano-catalyst is successfully prepared through an etching synchronous doping strategy. The composite material can be used for catalyzing ozone to degrade organic pollutants in water. Nitrogen doping can promote formation of a metal-nitrogen coordination structure, and decomposition of ozone on the surface of the catalyst is facilitated. Fluorine modification can significantly enhance the hydrophilicity of the composite material and accelerate the solid-liquid reaction of ozone in a solution and a catalyst interface, and the strong electron withdrawing effect of fluorine can effectively adjust the electronic structure of the catalyst and promote the generation of strong oxidizing active oxygen species, thereby achieving efficient and rapid removal of pollutants. The water treatment method solves the problem of low ozone utilization rate in a conventional catalytic ozonation process, has the advantages of high reaction rate and stable treatment effect, and has a good application prospect.

According to the invention, rigid anthracene is introduced as a framework of bridged binuclear metal, a pyridylamino binuclear metal titanium-zirconium-hafnium catalyst is constructed, and the molecular weight of the obtained polymer can be effectively improved through the synergistic effect between the binuclear metal and the steric hindrance and electronic effect on the catalyst structure; the polyolefin elastomer (POE), the isotatic polypropylene (iPP) and the propenyl elastomer (PBE) are efficiently synthesized. The pyridylamino binuclear metal titanium-zirconium-hafnium catalyst has the advantages that synthesis is simple, raw materials are easy to obtain, and the product yield is high. In copolymerization of ethylene and alpha-olefin, the catalyst shows excellent activity (5.75 * 10 < 7 > g (POE). Mol <-1 > (M). H <-1 >) and alpha-olefin selectivity (the insertion rate reaches 16.2 mol%), and the polyolefin elastomer POE with excellent performance is prepared. In propylene polymerization, the regularity of the polypropylene chain segment can be effectively regulated and controlled by adjusting the steric hindrance and the electronic effect of the catalyst, and the regularity gt is prepared with high activity (3.84 * 10 < 7 > g (PP). Mol <-1 > (M). H <-1 >); and the polypropylene material with high stereoregularity is prepared from 80 mmmm% of polypropylene with high stereoregularity. In copolymerization of ethylene and propylene, an elastomer material which takes propylene as a main material, can regulate and control the ethylene content to be 5-50 wt% and has unique characteristics of a propylene-ethylene semi-crystalline copolymer is prepared. In addition, the pyridylamino binuclear metal titanium-zirconium-hafnium catalyst also shows excellent high-temperature resistance (higher than 160 DEG C), is suitable for high-temperature solution polymerization, and can be used for preparing high-performance polyolefin elastomers. Therefore, the invention has original innovation, and provides a new direction for the development of the field of polyolefin materials.

The invention discloses a derivative of a rice bran extract as well as a preparation method and application of the derivative. A C-3 benzoate prodrug system is constructed, the transmembrane absorption efficiency is remarkably improved by optimizing the oil-water partition coefficient, fixed-point slow release of active ingredients is achieved through inflammatory tissue esterase, and high bioavailability and low irritation are both considered. Meanwhile, C-25 fluorine atoms are introduced to serve as biological electron isosteres, and target affinity is enhanced by means of the unique electronic effect and polar hydrophobicity of the C-25 fluorine atoms; spatial conformation is locked through side chain saturation, so that the compound shows anti-inflammatory and tissue repair activity which is obviously superior to that of natural cycloartanol under the same dosage.

The present application relates to a kind of multifunctional saponins molecularly imprinted polymer template molecule, molecularly imprinted polymer and its application, belong to plant component refining technical field.The molecularly imprinted polymer of the present application uses virtual template molecule, the template molecule contains hydrogen bond donor and strong electronic effect, it has good adsorption performance to natural saponins compound molecules such as Jiumu saponin AIII, Jiumu saponin BII, Jiumu saponin BIII, Sanqi saponin R1, ginsenoside Rg1, ginsenoside Rg3, ginsenoside Rh2, Tribulus saponin K, Tribulus saponin D, Platanus orientalis saponin D, Shandeng saponin B, Chonglou saponin I, Chonglou saponin II, Chonglou saponin VI.The virtual template molecule is low in cost, can be used for the large-scale preparation of molecularly imprinted polymer, significantly reduces the extraction cost of natural saponins compound.

The application belongs to the technical field of catalytic synthesis, and particularly relates to application of a Lewis acid-base pair in catalyzing polymerization of functionalizable monomers. Common polymerization methods have poor controllability for polymerization of monomers containing polyene groups, alkyne groups and conjugated diene groups, and the molecular weight of the obtained polymer is uncontrollable at low monomer conversion, and the molecular weight distribution is wide, and crosslinking occurs at high monomer conversion. The application utilizes a specific Lewis acid-base pair, and by adjusting the electronic effect and steric hindering effect of the Lewis acid and the Lewis base, active controllable polymerization of the functionalizable monomers can be catalyzed, and a polymer with a clear structure and containing functionalizable sites is obtained, the molecular weight is controllable, the molecular weight distribution is narrow, the end group structure is controllable, the position and density of the functionalizable sites are conveniently adjusted, an efficient platform is provided for post-modification preparation of functional high molecular materials, and functional high molecular materials are prepared by combining click reaction.

The invention discloses a transition metal catalyst based on a terpyridine ligand, a preparation method and application thereof, and particularly relates to application of the transition metal catalyst in the field of catalyzing copolymerization of olefin and polar monomers, the structural formula of the metal catalyst is shown in the specification, and R1 is selected from any one of a hydrogen atom electron-donating group or a fluorine atom electron-withdrawing group; and R2 is selected from a hydrogen atom electron-donating group. According to the scheme, terpyridyl with excellent coordination capability is used as a ligand to prepare the transition metal catalyst, and the electronic effect of the ligand is regulated and controlled, so that the catalytic performance of the catalyst is optimized, and favorable regulation and control on the catalytic activity, the relative molecular mass and distribution of a polymer, the copolymerization performance and the like are realized.

The invention belongs to the technical field of electrochemical materials, and particularly relates to a cobalt-nickel-iron ternary monatomic monolithic electrode and a preparation method and application thereof. The preparation method comprises the following steps: preparing cobalt-nickel-iron precursor solutions respectively, coating the cobalt-nickel-iron precursor solutions on the front and back surfaces of foamed nickel, and further performing high-temperature calcination in a hydrogen-argon mixed gas atmosphere to form a catalyst which is anchored on a three-dimensional porous foamed nickel substrate and has cobalt-nickel-iron ternary monatomic atoms, and the catalyst is used as an anode for hydrogen production by electrolysis of water for oxygen evolution (OER) reaction. According to the synthesis method, use of an insulating binder is avoided, excellent electron transmission capacity is ensured, electrolyte infiltration and rapid release of oxygen bubbles are greatly promoted through the three-dimensional porous structure, the synergistic electron effect of multi-element metal, the maximum atom utilization efficiency and an ideal mass transmission channel are combined, and the performance of the material is improved. And a solution with great application potential is provided for developing an efficient and low-cost water electrolysis hydrogen production anode.

This invention discloses a zinc-based mixed imidazole ligand metal-organic framework (ZIF) adsorbent material for highly efficient separation of CF4 / N2 and its preparation method. By strategically controlling the ratio of benzimidazole and 2-nitroimidazole ligands, a series of ZIF materials with large specific surface areas and suitable pore structures for adsorbing and separating CF4 / N2 are prepared. The 2-nitroimidazole provides a certain polarization effect to the framework, and its own electron-withdrawing effect and relatively long Zn-N bond length (easily broken) make it suitable as a parent material for ligand exchange. The benzene ring on the benzimidazole provides more adsorption sites for the framework. The metal-organic framework adsorbent material prepared by this invention can achieve highly efficient adsorption of CF4 and selective separation of CF4 / N2, exhibiting excellent performance and significant economic and social benefits.

The invention discloses an N-alkoxy quaternary ammonium salt chiral catalyst which can be used as a hydrogen atom transfer reagent and a catalyst for free radical reaction to mediate C-C bond coupling and alkylation reaction. A series of N-alkoxy quaternary ammonium salt chiral hydrogen atom transfer reagents are synthesized for the first time by introducing alkoxy on a chiral quaternary ammonium salt catalytic central nitrogen atom of a binaphthalene skeleton. Compared with a chiral binaphthalene skeleton-based chiral phase transfer catalyst (a catalytic center nitrogen atom is connected with an aliphatic carbon chain or aromatic carbon) developed by an applicant in an earlier stage, the catalyst provided by the invention has the advantages that alkoxy is introduced to the catalytic center N atom, so that the N atom is directly connected with an oxygen atom, and the electronic effect and bond breaking mode of the catalytic center are changed; a quaternary ammonium salt chiral catalyst participates in a free radical reaction instead of participating in an ionic reaction traditionally, C-C bond coupling which is difficult to complete under the ionic reaction condition is achieved, and a feasible scheme is provided for C-C bond construction and alkylation based on free radical chemistry.

The invention discloses a bimetallic catalyst for high-selectivity preparation of hexafluoropropylene oxide and application of the bimetallic catalyst, and belongs to the field of catalysts. The active component of the bimetallic catalyst disclosed by the invention is gold-palladium (Au-Pd) alloy nanoparticles loaded on an anatase type TiO2 carrier. Wherein the molar ratio of Au to Pd is (1: 1)-(3: 1), the Au-Pd alloy can give full play to the unique electronic effect within the proportion range, namely, the d-band center of Pd moves downwards, Au is in an electron enrichment state, and the Au-Pd alloy and the Au are in a synergistic effect, so that the oxygen adsorption and activation capacity is remarkably optimized. When the catalyst is applied to preparation of HFPO through HFP gas-phase catalytic oxidation, the bottlenecks of low conversion rate and selectivity, severe reaction conditions and short catalyst life in the prior art can be overcome, and technical support is provided for green and efficient industrial production of HFPO.

The application provides application of phosphorus ylide organophosphine as Lewis base in catalysis of polar vinyl monomer polymerization, and belongs to the technical field of polymer synthesis. The application utilizes phosphorus ylide organophosphine as Lewis base, and through Lewis base and Lewis acid synergistic catalysis of polar vinyl monomer polymerization under the cooperation of Lewis acid, realizes active controllable polymerization of polar vinyl monomer by changing steric hindrance and electronic effect of Lewis acid and Lewis base, and can realize active controllable homopolymerization and copolymerization (random copolymerization and block copolymerization) of different polar vinyl monomers. The molecular weight of the obtained polymer increases with the increase of the monomer to catalyst ratio, so that the system can realize the molecular weight of the polymer reaching more than 10 6 g / mol, the measured value of the molecular weight of the obtained polymer is basically consistent with the theoretical value, the monomer conversion rate is 100%, and the initiation efficiency is close to 100%.

The invention provides a bidentate cobalt complex containing an imidazo [1, 2-alpha] pyridine group as well as a preparation method and application of the bidentate cobalt complex, and belongs to the technical field of organic chemical synthesis. The structural formula of the bidentate cobalt complex is shown in the specification, and the preparation method comprises the following steps: carrying out bromination reaction and cyclization reaction on 2-methoxy-6-acetylpyridine to obtain a bidentate ligand with methoxy and imidazo [1, 2-alpha] pyridyl, and carrying out demethylation reaction on the ligand to obtain another bidentate cobalt complex with hydroxyl and imidazo [1, 2-alpha] pyridyl. The imidazo [1, 2-alpha] pyridyl-containing bidentate cobalt complexes are prepared from imidazo [1, 2-alpha] pyridyl-containing bidentate ligands, and the two ligands react with anhydrous cobalt chloride respectively to obtain various imidazo [1, 2-alpha] pyridyl-containing bidentate cobalt complexes. The electron effect of the complex is adjusted by changing substituent groups on imidazo [1, 2-a] pyridine groups, then the activity of the complex in catalytic reaction is adjusted, and the complex can be further applied to hydrosilylation reaction of styrene and has very important application prospects.

The invention discloses a preparation method and application of an electrolytic water anode oxygen evolution catalyst. The method comprises the following steps: dissolving a nickel salt, a molybdenum salt and a sulfur source in water, and adjusting the pH value to be acidic to obtain an electrodeposition electrolyte; a three-electrode system composed of a conductive substrate, a counter electrode and a reference electrode is inserted into the electro-deposition electrolyte and electrified, and the electrolytic water anode oxygen evolution catalyst is electro-deposited on the conductive substrate. The catalyst prepared by the preparation method disclosed by the invention has rich nano structures and electronic effects, and can show relatively high intrinsic catalytic activity; and meanwhile, the catalyst is tightly combined with the conductive substrate, so that the cycling stability of the material in alkaline electrolyte is further ensured. The water electrolysis oxygen evolution reaction catalyst prepared by the one-time electrodeposition method has the advantages of simple process, easiness in scale production, no need of additional addition of a binder, direct in-situ growth on a conductive substrate, and improvement of the binding force of the catalyst and the substrate, so that the charge transfer efficiency and the structural stability are improved, and the method has a good application prospect in water electrolysis anode oxygen evolution.

The invention discloses a binuclear enhanced ethylene selective tetramerization catalytic system and its application, belonging to the field of polymerization catalysts. The catalytic system of the present invention includes ligand a, transition metal compound b and activator c, wherein ligand a is composed of three parts: PNP ligand, PNNP ligand and rigid linking group. The present invention adopts a rigid group with a substituted group to connect PNP and PNNP, suppresses the interaction of the catalyst active center, reduces catalyst degradation and inactivation, and simultaneously passes through the large π bond of the linking group and the ligand skeleton through p-π conjugation, effectively transmits the electronic effect of the substituent on the linking group to the ligand, and has little influence on its steric group effect, thereby achieving the purpose of enhancing the thermal stability of the catalyst and maintaining its good 1-octene selectivity.

The application provides a preparation method of a carbon material Ru-based catalyst and application of the carbon material Ru-based catalyst in partial hydrogenation of benzene to cyclohexene. According to the activity test results, the introduction of the carbon material improves the benzene conversion rate and appropriately increases the selectivity of cyclohexene. This is mainly due to the rich functional groups on the surface of the carbon material and the unique electronic effect, which increases the dispersion of the metal Ru and stabilizes the Ru δ+ In the reducing reaction system. The application selects a fixed bed as an evaluation device of the cyclohexene, avoids the problems such as difficult separation of products and catalysts in the traditional autoclave device, is beneficial to continuous production of the cyclohexene and provides certain convenience for subsequent industrial application.

The application provides a Pd-Cu bimetallic supported In2O3-TiO2 catalyst and a preparation method and application thereof, and belongs to the technical field of CO2 hydrogenation to prepare methanol. The catalyst comprises a composite carrier and Pd nanoparticles and Cu nanoparticles supported on the surface of the composite carrier. Pd and Cu are combined to form bimetallic sites in the application, the advantages of the bimetallic sites can be fully exerted, and the reaction activity of CO2 hydrogenation to prepare methanol can be significantly improved through the electronic effect and geometric effect between the metals. The Pd-Cu / In2O3-TiO2 catalyst provided by the application has the advantages of high conversion rate and high catalytic activity in the reaction of carbon dioxide hydrogenation to prepare methanol; wherein, in the process of carbon dioxide hydrogenation, the Pd-Cu / In2O3-TiO2 catalyst can obtain a one-way CO2 conversion rate of 23.5% and a methanol yield of 15.83% at 250 DEG C.

This invention provides an anthracene-based fluorescent material, its preparation method, and its applications. The anthracene-based fluorescent material is as shown in Compound I. The compounds of this invention utilize the electron-donating effect of aromatic amine units such as carbazole and the electron-withdrawing effect of phosphonyl / sulfonyl groups, effectively improving the electron and hole transport capabilities of the molecules. Furthermore, the steric hindrance effect, resulting in a distorted molecular configuration, can suppress intermolecular interactions, thereby reducing the device efficiency roll-off caused by concentration quenching. The thermal exciton mechanism enables these molecules to achieve an exciton utilization rate exceeding that of traditional fluorescent molecules by 25%.

The invention discloses a preparation method and application of a Br and N co-doped cobalt-based monatomic catalyst, and relates to the technical field of preparation of catalytic materials. A zeolite imidazole framework ZnCo-ZIF is selected as a precursor and is pyrolyzed, NH4Br is adopted as a nitrogen source and a bromine source to optimize the prepared conventional cobalt-based monatomic catalyst, and a chemical vapor deposition technical synthesis method is utilized to modify the catalyst, so that the cobalt-based monatomic catalyst is prepared. Through the synergistic effect of short-range regulation and control of a first shell coordination microenvironment of Co and long-range regulation and control of an induced electron effect in a carbon matrix, an electronic structure of a Co site is effectively regulated and controlled, and the intrinsic catalytic activity of the catalyst is improved, so that generation of singlet oxygen and degradation of pollutants are enhanced. Compared with a conventional cobalt-based monatomic catalyst, the prepared catalyst has the advantage that the catalytic performance is remarkably improved. Meanwhile, the prepared catalyst is mild in reaction condition, has excellent acid and alkali resistance, good anti-interference capability and excellent durability, and has wide practical application potential.

The invention provides a catalyst for preparation of methanol by hydrogenation of carbon dioxide and a preparation method and application thereof, a carrier of the catalyst for preparation of methanol by hydrogenation of carbon dioxide comprises a zirconia skeleton carrier of an octahedral cage structure, and active components are loaded on the surface and pore inner walls of the carrier, the zirconium oxide skeleton carrier with an octahedral cage structure can carry out space and electronic regulation and control on a loaded metal active center through a geometric confinement effect and an electronic effect, and the zirconium oxide skeleton carrier is high in reaction selectivity, high in activity and high in stability when being applied to a catalytic reaction for preparing methanol through carbon dioxide hydrogenation, and has an industrial application prospect.

The invention discloses synthesis and application of a pyridine-containing asymmetric alpha-diimine nickel catalyst and application of Lewis acid regulation in olefin polymerization, and belongs to the technical field of olefin polymerization. In the olefin polymerization reaction catalyzed by the diimine nickel catalyst, the Lewis acid plays a very ingenious role of a regulator, and the electronic property and space environment of the active center of the catalyst are changed by introducing the Lewis acid salt, so that the dual regulation of the steric hindrance and the electronic effect of the catalyst is realized; the performance of the catalyst is improved; and the structure of the final polymer is changed. Compared with known alpha-diimine nickel catalysts, the alpha-diimine nickel catalyst has the advantages of high polymerization activity, strong thermal stability and improvement of monomer insertion rate.

The application discloses a kind of hexafluorosilicic acid anion functionalized microporous material and its preparation method and application in adsorption separation olefin / alkane.The microporous material is by metal ion Zn 2+ , inorganic anion SiF6 2‑ And azole organic ligand L are formed by the coordination of static solvothermal reaction polymer, the microporous material with the separation property can only be synthesized using static solvothermal reaction method.The microporous material has high density of anion and azole site, and the structure properties of the material can be controlled by adjusting the solvent type of the reaction, the feeding ratio of anion and azole organic ligand and the type of azole organic ligand.The microporous material obtained by the application can realize the separation of olefin / alkane based on size and electronic effect.

The present invention discloses a catalyst for catalytically synthesizing C8+ higher alcohols from ethanol at low temperature, a preparation method thereof, and a method for synthesizing C8+ higher alcohols; aiming to provide a catalyst Ni / MOFC prepared by combining impregnation and two-step annealing methods. In this catalyst, Ni forms a coordination with N, optimizing the electronic structure of the metal surface, having highly dispersed active sites and a unique electronic effect, reducing the ethanol dehydrogenation energy barrier, thereby enabling the catalytic generation of C8+ higher alcohols from an ethanol aqueous solution at an extremely low temperature, and having good catalytic efficiency and selectivity.

This invention discloses a class of porphyrin-based A-D-A type polymer photovoltaic materials, their preparation methods, and applications. The invention utilizes a porphyrin-DPP system constructed through Sonogashira coupling, placing the donor unit at the center of the A-D-A structure. This A-D-A structure more effectively enhances the intramolecular push-pull electronic effect, promoting intramolecular charge transfer and thus significantly broadening and redshifting the light absorption range of the polymer. Furthermore, the A-D-A structure facilitates more ordered and compact intermolecular stacking, promoting the expansion of π-π conjugation and potentially increasing the carrier mobility of the material. This lays the material foundation for obtaining higher short-circuit current densities and fill factors in devices.

The invention relates to the technical field of catalytic materials, in particular to a heteroatom-modulated diatomic catalyst and a preparation method and application thereof.The preparation method comprises the steps that binuclear metal complex molecules, zinc salt and an organic solvent are mixed, an obtained mixed solution and a 2-methylimidazole solution are stirred and mixed under the dark condition, and a mixture is obtained; and carrying out heat treatment on the obtained composite material to obtain the heteroatom-modulated diatomic catalyst. The method comprises the following steps: introducing a binuclear metal complex molecule containing heteroatoms into MOF in advance, and carrying out further heat treatment to construct a stable diatomic active center in which the heteroatoms participate in regulation on a nitrogen-doped carbon substrate; the introduction of heteroatoms not only can enhance the stability of diatomic sites and prevent agglomeration of the diatomic sites in heat treatment and electrochemical processes, but also can generate a strong catalytic effect through the unique geometric and electronic effects and fine regulation and control of the electronic structure of the binuclear center of the diatoms, thereby significantly improving the intrinsic activity and stability of the diatomic sites to ORR.

This invention relates to the field of catalyst technology, specifically to a twinned palladium catalyst, its preparation method and application, and a method for hydrogenating carboxybenzaldehyde. The twinned palladium catalyst contains palladium and carbon and has a spherical morphology. The spherical shape of the twinned palladium catalyst not only provides abundant surface reaction sites for the hydrogenation reaction, but the synergistic electronic effect caused by the twinned interface also significantly improves the catalyst's activity and stability. When used for the hydrogenation of carboxybenzaldehyde (e.g., p-carboxybenzaldehyde), it has the advantages of high substrate conversion and high catalyst stability.

The invention discloses high-crosslinking sulfonated polyhalogen styrene resin as well as a preparation method and application thereof. The preparation method of the resin comprises the following steps: firstly, enabling halogen styrene to react with a cross-linking agent to form a gel polymer; then carrying out sulfonation reaction on the gel polymer by utilizing a sulfonation reagent to obtain a sulfonated polymer; finally, post-crosslinking is realized through a Friedel-Crafts alkylation reaction, and the sulfonated resin with a high-crosslinking structure is prepared. According to the resin, deep removal of metal ion impurities is achieved through multiple action mechanisms (including ion exchange, electrostatic adsorption and coordination) between sulfonic acid groups and metal ions, and the chemical stability of the resin in an organic wet electron chemical system is remarkably enhanced by means of the electron withdrawing effect of halogen atoms and the synergistic effect of a post-crosslinking structure. In addition, halogen atoms on the surface of the resin can form hydrogen-bond interaction with hydroxyl-containing organic impurities, so that the organic impurities are synchronously removed. The highly crosslinked sulfonated polyhalogen styrene resin prepared by the method can effectively purify wet electronic chemicals, is particularly suitable for high-purity preparation of semiconductor photoresist solvents, and provides a novel efficient purification solution for the field of advanced electronic materials.

The application discloses a kind of N-alkoxy quaternary ammonium salt chiral catalyst, can be used as hydrogen atom transfer reagent and catalyst of radical reaction, mediate C-C bond coupling and alkylation reaction.The alkoxyl group is introduced on the chiral quaternary ammonium salt catalytic center nitrogen atom of binaphthyl skeleton, and a series of N-alkoxy quaternary ammonium salt chiral hydrogen atom transfer reagent is synthesized for the first time.Compared with the chiral phase transfer catalyst based on chiral binaphthyl skeleton (catalytic center nitrogen atom is connected with aliphatic carbon chain or aromatic carbon) developed by applicant earlier, the catalyst of the application introduces alkoxyl group on catalytic center N atom, so that N atom is directly connected with oxygen atom, changes the electronic effect and bond breaking mode of catalytic center, changes the traditional participation of quaternary ammonium salt chiral catalyst in ionic reaction into participation in radical reaction, realizes the C-C bond coupling difficult to complete under ionic reaction condition, and provides a feasible scheme for C-C bond construction and alkylation based on radical chemistry.