37 results about "Cis trans isomerization" patented technology

The invention discloses a method for preparing fumaric acid through the cis-trans isomerization of maleic acid. The method comprises the following steps of: taking maleic acid as a raw material in the presence of air or oxygen according to the mass ratio of raw material to the solvent being 1:1-1:80, wherein the solvent contains N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), ethyl acetate, benzene, methylbenzene or nitrobenzene; controlling conditions that the reaction pressure is under 0.1-1.2Mpa and the temperature is 50-150 DEG C, reacting for 1-12 hours by taking monometallic porphyrin in formula (I) or mu-oxo bimetal porphyrin in formula (II) or immobilized metal porphyrin formed as catalysts, wherein the concentration of the catalysts is 5-160PPM; and performing isomerization of maleic acid to obtain the product fumaric acid. The method has the following technical effects of being small in catalyst usage amount, high in catalytic efficiency, free from corrosion action to the equipment, high in conversion rate, high in product yield, and low in production cost.

The invention relates to a preparation method of a nanocellulose-based azobenzene-containing random polymer. The preparation method comprises the following steps: preparing nanocellulose by virtue of a sulfuric acid hydrolysis method under the action of a homogenizing instrument, carrying out bromination modification on the surface of the nanocellulose by utilizing 2-bromoisobutyryl bromide, and finally, randomly co-polymerizing azobenzene-containing acrylate monomers and N, N-dimethylamino-ethyl methacrylate by adopting the bromized nanocellulose as a macromolecular initiator by an atom transfer free-radical polymerization method to obtain the nanocellulose-based azobenzene-containing random polymer. The nanocellulose-based azobenzene-containing random polymer is prepared into a film with various responsiveness to temperature, pH and light by virtue of a solvent evaporation method or a spin coating method, and the collapse and stretching variation of N, N-dimethylaminoethyl ester or the interconversion of light-induced cis-trans isomerization process of azobenzene groups on the surface of the film is changed by regulating and controlling the variation of the external temperature, pH and light, so that the variation of the hydrophilic-hydrophobic property is realized on a macro scale, the variation of the internal aperture of the film is indirectly changed, and an effect of flexibly regulating and controlling the aperture of the film is realized.

The invention discloses a photosensitive chiral macrocyclic molecule and a preparation method and application thereof, belonging to the field of preparation of photoresponsive materials. The preparation method for the photosensitive chiral macrocyclic molecule adopts the following steps: a) reacting oligomeric ethylene glycol, sodium hydroxide and p-toluenesulfonyl chloride in a tetrahydrofuran solvent in an inert atmosphere so as to obtain an intermediate 1; b) dissolving the intermediate 1, cesium carbonate and dibenzo-18-crown-6 in an N-N dimethylformamide solvent and carrying out a reaction in an inert atmosphere so as to obtain an intermediate 2; and c) dissolving the intermediate 2, chiral binaphthol compounds, cesium carbonate and dibenzo-18-crown-6 in the N-N dimethylformamide solvent and carrying out a reaction in an inert atmosphere so as to obtain a target product. The photosensitive chiral macrocyclic molecule provided by the invention has the advantages of easy synthesis, good stability, ability of selective complexation of chiral ammonium salt and capability of realizing complexation and release of chiral ammonium salt through an azo cis-trans isomerization behavior.

The invention discloses a compound taking quinolizine ketone as a mother nucleus and for treating or preventing hepatitis B virus infection. The compound comprises optical isomer, raceme, cis-trans-isomer and any combination thereof or medicinal salt thereof. The invention further discloses a preparation method and application of the compound. The compound can remarkably lower in-vivo HBsAg leveland inhibit duplication of HBV, has good medicinal attribute and is low in toxicity, and pharmacokinetic and pharmacodynamic functions are improved; efficiency of combining with the HBV can be improved greatly, and clearance rate of in-vivo HBV can be further increased.

An information recording medium includes a recording layer, in which information is recorded by two-photon absorption that occurs when recording light is focused on the recording layer. The recording layer (211, 212) contains a photosensitive polymer that includes a principal chain containing acrylate or methacrylate and a first side chain and a second side chain branched from the principal chain. The first side chain undergoes a cis-trans isomerization reaction upon absorption of the recording light, and the second side chain has a property of being oriented in about the same direction as a direction of the first side chain when the first side chain undergoes the cis-trans isomerization reaction.

The invention discloses a solid phase microextraction method of unsaturated fatty acid. A silver nanoparticle immobilized monolithic column is used as a solid phase microextraction monolithic column, and the solid phase microextraction method of unsaturated fatty acid is established in combination with an in-tube solid phase microextraction-high performance liquid chromatography system. The unsaturated fatty acid is enriched under the interaction of silver nanoparticles on the surface of the monolithic column and carbon-carbon double bonds of the unsaturated fatty acid; different isomers of the unsaturated fatty acid are sequentially eluted under different acting forces between the silver nanoparticles and the isomers of the unsaturated fatty acid. The method is simple, the process is ingenious, required instruments have higher popularization degree, the method is easy to popularize, efficient enrichment of the unsaturated fatty acid and sequential elution of different cis-trans-isomers can be realized, and the efficient detection requirement of trans-fatty acid can be met.

The invention discloses a method for preparing trans-1,2-dichloroethylene. The method includes the steps that isomerization of cis-1,2-dichloroethylene is performed under the action of a transpositioncatalyst to obtain trans-1,2-dichloroethylene, the reaction temperature is 150-250 DEG C, the residence time is 0.5-5 h, the reaction pressure is normal pressure, and the product obtained by the reaction undergoes purification by rectification to obtain trans-1,2-dichloroethylene. The transposition catalyst is adopted to perform cis-trans isomerization of 1,2-dichloroethylene, the process is simple, the product is easy to separate and purify, and the generated crude product undergoes operations of rectification and purification and the like to obtain the pure trans-1,2-dichloroethylene.

A detection method of cis-trans isomers in cis-propenyl phosphonic acid and related impurities thereof is applicable to the field of pharmaceutical analysis, and the method comprises the following steps and conditions: the chromatographic conditions are that the chromatographic column is a C-18 column of 4.6 mm*250 mm*5.0 microns; the flow velocity is 1.0 ml / min; an ultraviolet detector has a detection wavelength of 225 nm and a sample size of 10 microliters; the mobile phase is 50 mmol / L dipotassium hydrogen phosphate aqueous solution-methanol; preparing a test solution by dissolving 0.1 microliters of test samples in the mobile phase, diluting to 25 ml, and filtering; introducing 10 microliters of the test solution, recording a spectrum, wherein the retention time for cis-propenyl phosphonic acid is 12.3 min, the relative retention value of its cis-trans isomers is 1.15, and the relative retention value of propadiene phosphonic acid is 0.38, and calculating the contents of various impurities by an area normalization method; in the mobile phase, the 50 mmol / L dipotassium hydrogen phosphate aqueous solution contains 2% of tetrabutylammonium hydroxide aqueous solutions; the concentration of the tetrabutylammonium hydroxide aqueous solution is 55%. According to the invention, the method is used for the detection of cis-trans isomers in cis-propenyl phosphonic acid and related impurities thereof, and the repeatability, the sensitivity, and the accuracy all meet the requirements.

The invention discloses a catalyst for continuously preparing 3,5-dimethyl piperidine. The catalyst is prepared from an activated carbon carrier, Ru, Rh and M, wherein the Ru, the Rh and the M are loaded on the activated carbon carrier, the mass percent content of the Ru in the catalyst is 1% to 5%, the mass percent content of the Rh is 0.05% to 1%, the mass percent content of the M is 0.05% to 1.5%, and the M is Pt, K, Ce or Sn. In addition, the invention further discloses a preparation method of the catalyst and a method for continuously preparing the 3,5-dimethyl piperidine. The catalyst disclosed by the invention has the characteristics of high activity, high selectivity and high stability and can can realize high-efficient catalysis to prepare the 3,5-dimethyl piperidine in high efficiency; the converting rate of a raw material of 3,5-dimethyl pyridine is 100%, the yield of a product of the 3,5-dimethyl piperidine is larger than 99%, and cis-trans isomerism ratio is (87 : 13) to ( 83 : 17).

The invention discloses an azo hydrophilic compound as well as a preparation method and application thereof. The azo hydrophilic compound comprises a carboxylic acid type azo hydrophilic compound or a sulfonic acid type azo hydrophilic compound. During the self-emulsifying process that the azo hydrophilic compound provided by the invention is used as a chain extender to form a polyurethane emulsion, the azo hydrophilic chain extender with good hydrophilic property is distributed on the surfaces of emulsified ball particles to form a stable double-electrode-layer structure, and the cis-trans isomerization efficiency can reach 100%; the variation of the particle diameter of the polyurethane emulsion under the ultraviolet irradiation shows that the functional material can be used as an ultraviolet responsive nano-carrier, and has potential application prospect in the aspect of forming azo water-soluble polyester and other color-changing polymer materials.

The invention belongs to the technical field of liquid crystal materials, in particular to a method for controlling a liquid crystal reflection color by using fluorine substituted azobenzene. The fluorine substituted azobenzene used in the method has the characteristic of multi-wavelength light response, and the cis-trans isomerization reaction with different degrees of the fluorine substituted azobenzene can be carried out under the irradiation of different wavelength lights. According to the method, the fluorine substituted azobenzene, a chiral dopant and a liquid crystal matrix are evenly mixed in a certain proportion, and then the mixture is poured into a liquid crystal cell. By changing a wavelength of a stimulus light source, the precise regulation of the reflection color of the liquid crystal cell to be red, green and blue can be realized. The control method uses the light steady state to control the liquid crystal reflection color, and the limitation of a traditional method that the transition state is used to control the reflection color is broken through. The method can be applied to numerous fields, such as liquid crystal display, optical logic switch, optical storage, anti-counterfeiting, and the like.

The invention relates to a preparation method of antisotropic azo polymer / carbon tube composite thin film with photo-responsitivity. An azo polymer and a modified carbon tube composite film are prepared into a flexible polymer thin film with in plane anisotropy through synthesis of the azo polymer and modification of a carbon tube film; a flexible thin film with in-plane conducting anisotropy can be obtained through polymer molecular chains are orientated along a carbon tube under the induction of the carbon tube, and the conductivity in the in-plane horizontal direction is higher than that in the direction which is vertical to the carbon tube by one order of magnitude; under UV (Ultraviolet) irradiation, the conductivity of an azo polymer-carbon tube composite film is changed, and since azo molecules are in cis-trans isomerization under the UV irradiation and the molecular distance of a cis structure is reduced, higher conductivity is obtained; the conductivity of the azo polymer-carbon tube composite flexible thin film has good repeatability along with the change of irradiation, and good photo-responsitivity is expressed by the azo polymer-carbon tube composite flexible thin film; the antisotropic azo polymer / carbon tube composite thin film is expected to be applied to many fields of aerospace, organic photoelectric devices and the like.

The invention belongs to the technical field of medicines. The invention provides a pyrrolidone compound, its optical isomer, raceme and cis-trans-isomer and any combination thereof or its pharmaceutically acceptable salt which are shown as formula (I). The compounds of the invention can be used as small molecule inhibitors of p53-MDM2 (murine double minute2) / X protein interacting. The compounds of the invention can be used for preparing antitumor drugs or anti-inflammatory drugs.

The invention relates to preparation and application of a dialdehyde-built nitrogen-containing or oxygen-containing heterocyclic compound with the insecticidal activity, provides a compound with the structure represented by formulas (A), (B), (C) or (D) or an optical isomer and a cis-trans-isomer of the compound or agriculturally and pharmacologically acceptable salt and also relates to an agricultural combination comprising the compound or the optical isomer and the cis-trans-isomer of the compound or the agriculturally and pharmacologically acceptable salt, application of the agricultural combination and a preparation method for the compound or the optical isomer and the cis-trans-isomer of the compound or the agriculturally and pharmacologically acceptable salt. The compound and derivatives thereof are high in insecticidal activity to homoptera, lepidoptera and other types of agroforestry pests such as aphids, plant hoppers, aleyrodids, leafhoppers, thrips, cotton bollworms, cabbage caterpillars, plutella xylostella, prodenia litura and armyworms.

The invention discloses a Millepachine-CA-4 derivative as well as a preparation method and application thereof. The derivative is good in stability, high in anti-tumor activity and small in toxic andside effects, effectively overcomes the defects that CA-4 has cardiovascular toxicity at a high dose and CA-4 is unstable, prone to photolysis, prone to cis-trans isomerization, poor in water solubility and the like, and the derivative can be used for preparing anti-tumor drugs.

The invention provides a method for producing all trans-teprenone, comprising the following steps of: (1) synthesizing teprenone through Carroll reaction to obtain a teprenone crude product; (2) pickling the teprenone crude product by the use of hexane and sulfuric acid, carrying out alkali washing by the use of a sodium bicarbonate solution, washing to neutral, and removing an emulsification layer and a water layer to obtain mixed teprenone after washing; (3) adding hexane for dilution, standing at minus 15-minus 20 DEG C for 20-24 hours, cooling to minus 30-minus 60 DEG C, and crystallizing all trans-teprenone; and (4) centrifuging the crystals at minus 20-minus 40 DEG C to obtain the all trans-teprenone having a purity of greater than 99%. Through an ultralow temperature separation method and an apparatus, all trans-teprenone having a purity of greater than 99% is obtained from a cis-trans isomer which is hard to separate under the condition of high temperature and other purities which can be separated by a rectification means. In addition, cis and other impurities do not exceed 1%.

The invention discloses a preparation method and an application of an isomerization catalyst and aims to solve the problem of low yield of a target product due to presence of an isomer in a productionprocess of the compounds. A precursor of the catalyst is prepared from composite oxide or the composite oxide which is impregnated with a certain amount of metal salt, the precursor of the catalyst is roasted at 350-450 DEG C, subjected to sheet forming and compression forming, and subjected to HF fluoridation at 200-400 DEG C, and the fluorination catalyst is prepared. The catalyst is mainly applied to a cis-trans isomerization reaction process of hydrofluoro olefin or hydrochlorofluoro olefin.

The invention provides a preparation method of a photoresponse film, which comprises the following steps of: dissolving chitosan powder in an acetic acid aqueous solution, adding 4,4'-dihydroxyazobenzene dissolved in a strong polar solvent, fully stirring, removing visible bubbles in the solution, standing in a 5 DEG C environment under protection of nitrogen, uniformly pouring a clear solution into a mold, placing the mold in a constant-temperature oven to remove the solvent, taking out after 40 hours, forming the film, and washing the film with a sodium hydroxide aqueous solution to remove the film to obtain a photoresponse unbraced film. Compared with the prior art, the preparation method of the photoresponse film saves complex operation and cost in a preparation process of a polymer; and meanwhile, an azobenzene derivative is combined with chitosan molecules by hydrogen bonds, so that the molecular size change in a cis-trans isomerization process of the azobenzene is amplified, ultraviolet light irradiation is bent to a comparatively large extent, the bending is restored under the irradiation of visible light, and model design of photoinduced artificial muscle is achieved.

The invention belongs to the technical field of polymer materials and specifically relates to a photo-repair azobenzene polymer and a preparation method thereof. The preparation method comprises the steps: firstly, carrying out multi-step reactions such as etherification, nitro-reduction, diazo coupling and esterification on p-nitrophenol to obtain monomers containing anthracene and azobenzene groups, namely 4'-(hexyl methacrylate-oxyl)-4-(anthracene-2-methylacetate)azobenzene(MMA-AZO-AN); and then, carrying out free radical polymerization on MMA-AZO-AN serving as a monomer under the conditionthat an initiator exists to prepare the 4'-(hexyl methacrylate-oxyl)-4-(anthracene-2-methylacetate)azobenzene(MMA-AZO-AN). The novel photo-repair azobenzene polymer is prepared by applying the cooperation of two photo-responsive structures in combination with a reversible Diels-Alder addition reaction generated by the anthracene group under the condition of light excitation and a reversible cis-trans isomerism behavior generated by azobenzene under the conditions of ultraviolet light and visible light excitation.

The invention belongs to the technical field of medicine. The invention provides cyclohexalipopeptide compounds, whose chemical formula is represented by the formula (I), including optical isomer, raceme, cis-trans-isomer, and pharmaceutically acceptable salts. The invention also provides a preparation method of the compounds and an application of the compounds in preparation of antifungal drugs.

The invention discloses a method for promoting cis-trans isomerization of an azobenzene derivative by utilizing black phosphorus nano-sheets. The method comprises the following steps: putting ground black phosphorus powder into an organic solvent; carrying out ultrasonic dispersion in a water bath, wherein the ultrasonic time is 6 to 8h; carrying out centrifugal separation on dispersed black phosphorus and taking supernatant; after mixing the supernatant and a solution of the azobenzene derivative, stirring for 1 to 2h to obtain a mixture solution; placing the mixture solution under a light-shielding environment. The method is more convenient and feasible to operate, the cis-trans isomerization speed of the azobenzene derivative can be effectively increased, and the highest speed can reachabout 20 times. An obtained black phosphorus and azobenzene derivative has excellent photoelectric properties of the black phosphorus and photo-isomerization properties of the azobenzene derivative,and has a certain application in the aspects of molecular switches, photoelectric materials and energy storage.

The invention discloses an electrochemical process for preparing fumaric acid employing maleic acid cis-trans isomerization. The electrochemical process is characterized by comprising the following steps: obtaining fumaric acid by taking a maleic acid solution as a raw material through the electrochemical process; partitioning an electrolytic cell into a cathode chamber and an anode chamber by adopting an ion exchange membrane, wherein electrolyte of the cathode chamber and the anode chamber is the maleic acid solution; adding sodium bromide to the electrolyte of the anode chamber; setting the temperature of the electrolyte at 25-85 DEG C, controlling the current density at 0.01-0.2A / cm<2> or constant pressure at 0.5-6.0V; and cooling, crystallizing, filtering and drying an anode electrolyte to obtain the fumaric acid after electrolyzing for 1-2 hours. By adopting the method disclosed by the invention, a nitrogen-containing compound is not added, the wastewater after solid-liquid separation can be recycled, a water resource can be efficiently utilized, and the problem that ammonia nitrogen of the fumaric acid wastewater exceeds the standard can be overcome from a source. Thus, the electrochemical process is a green production technology worthy of the name.

The invention relates to a preparation method of antisotropic azo polymer / carbon tube composite thin film with photo-responsitivity. An azo polymer and a modified carbon tube composite film are prepared into a flexible polymer thin film with in plane anisotropy through synthesis of the azo polymer and modification of a carbon tube film; a flexible thin film with in-plane conducting anisotropy can be obtained through polymer molecular chains are orientated along a carbon tube under the induction of the carbon tube, and the conductivity in the in-plane horizontal direction is higher than that in the direction which is vertical to the carbon tube by one order of magnitude; under UV (Ultraviolet) irradiation, the conductivity of an azo polymer-carbon tube composite film is changed, and since azo molecules are in cis-trans isomerization under the UV irradiation and the molecular distance of a cis structure is reduced, higher conductivity is obtained; the conductivity of the azo polymer-carbon tube composite flexible thin film has good repeatability along with the change of irradiation, and good photo-responsitivity is expressed by the azo polymer-carbon tube composite flexible thin film; the antisotropic azo polymer / carbon tube composite thin film is expected to be applied to many fields of aerospace, organic photoelectric devices and the like.

The invention relates to the technical field of photochromic coatings, and discloses a photochromic coating based on organic-inorganic hybridization and a preparation method of the photochromic coating. The photochromic coating comprises the following formula raw materials: a naphthalene tetraformyl diimide azobenzene derivative, phosphotungstic acid hydrate, lanthanum nitrate hexahydrate, a polyurethane dispersion, a film-forming auxiliary agent, a dispersing agent and a defoaming agent. According to the photochromic coating based on organic-inorganic hybridization and the preparation methodof the photochromic coating, when the C38H20N6O4R2 receives illumination, a -N=N- group generates a reversible cis-trans isomerization reaction, so that the yellow trans-C38H20N6O4R2 is converted intored cis-C38H20N6O4R2, and La<3+> in La3-PW12O40-C38H20N6O4R2 is very easily reduced; the generated electrons form electron radiation transition between PW12O40 and the ligand C38H20N6O4R2, so that the ultraviolet-visible absorption spectrum of the C38H20N6O4R2 has red shift to produce a good fluorescence emission phenomenon; and a ligand free radical is formed through the excited state electron transfer and the C38H20N6O4R2 to oxidize W<5+> into W<6+> to further promote the reversible photochromic phenomenon of a complex.

A method is described for exfoliating a microcrystal of an anthracene derivative by irradiation with short pulses of light having a wavelength of 220-420 nm. The irradiation induces a cis-trans isomerization of the anthracene derivative in a part of the microcrystal, which leads to the separation of an outer layer having a thickness of 200-600 nm. The exfoliated microcrystal may be irradiated again with pulses of light of a same or different wavelength.

The invention relates to the technical field of biological materials, and mainly relates to a photo-induced phase change cellulose material and a preparation method thereof. According to the preparation method, sodium carboxymethylcellulose and a quaternary ammonium salt compound containing azobenzene groups are combined in a water phase through electrostatic acting force to obtain a compound, and the compound is subjected to centrifugation and freeze drying treatment to obtain the photoinduced phase change type cellulose material. The prepared photo-induced phase change type cellulose material can realize storage and release of energy through cis-trans isomerization of azobenzene and phase change of the material under irradiation of ultraviolet light and visible light. The prepared photo-induced phase change cellulose material can be applied to the related fields of energy storage and the like.

The invention discloses an olefin isomerization catalyst system and its application. The catalyst system is an organic solution formed by dissolving the ruthenium complex RuH2CO(PPh3)3 and a second metal salt in a solvent. The second metal salt is a metal salt containing non-redox active metal ions. The molar ratio of the ruthenium complex RuH2CO(PPh3)3 and the second metal salt is between 1:0.5 and 1:4, and the concentration of the ruthenium complex RuH2CO(PPh3)3 is between 0.5 mmol / L and 5 mmol. / L between. The catalyst system of the present invention can be applied to olefin double bond isomerism, olefin cis-trans isomerism or olefin tautomerism containing hydroxyl functional groups, and solves the problem of air sensitivity and high temperature requirements of ruthenium complexes in catalyzing olefin isomerization systems. difficult problems, mild reaction conditions, high catalyst utilization, stable system, easy implementation, and low cost.