9 results about "Azo coupling" patented technology

The invention belongs to the field of organic synthesis, and relates to a preparation method of a material intermediate, in particular to a synthesis method of 3, 3 ', 4, 4'-tetraaminobiphenyl. The synthetic route comprises the following steps: (1) taking 4, 4 '-diaminobiphenyl as a raw material, and carrying out diazo coupling reaction on the 4, 4'-diaminobiphenyl and aromatic diazonium salt under an alkaline or neutral condition to form an intermediate 4, 4 '-diaminobiphenyl diazo compound as shown in a formula (I); and (2) carrying out catalytic hydrogenation reduction reaction on the intermediate obtained in the step (1) to obtain a finished product 3, 3 ', 4, 4'-tetraaminobiphenyl. The method has the advantages of short process route, no dangerous nitration reaction and no generation of nitric acid waste liquid. According to the method, conversion is achieved through three-step reaction, the molar yield can reach 87.7%, operation is easy, reaction conditions are mild, and therefore the effects of low cost and low pollution are achieved.

The present invention provides a method for preparing a nanosheet and its application in a proton exchange membrane, belonging to the fields of two-dimensional nanomaterial preparation technology and fuel cell membrane technology. The nanosheet is prepared by a diazo coupling reaction occurring at a microphase interface, and the interface area between the water and oil phases is expanded by vigorous stirring, so that the ultra-thin nanosheet can be prepared in large quantities. The nanosheet is directly processed into a membrane by blending with polybenzimidazole, and a blended high-temperature proton exchange membrane is obtained after doping with phosphoric acid, and its conductivity at 160°C reaches 95.0 mS cm ‑1 , which is much higher than the conductivity of polybenzimidazole under this condition, 37.9 mS cm ‑1 ; and the phosphoric acid loss rate of the blended high-temperature proton exchange membrane is only 26.3% under the conditions of 80°C and 40% relative humidity, while the phosphoric acid loss rate of polybenzimidazole under the same conditions is 45.9%, indicating that the ultra-thin nanosheets of the present invention can effectively improve the conductivity and inhibit the loss of phosphoric acid.

The invention discloses Fe < 3 + > visual sensing test paper based on colorimetric / fluorescent bimodal detection as well as a preparation method and application of the Fe < 3 + > visual sensing test paper. The test paper adopts a three-layer composite structure design: a filter paper substrate layer, a PEG intermediate layer and a bimodal sensing layer, and the sensing layer is loaded with 4 '-hydroxy-2, 4-diaminoazobenzene (L) and lignin blue fluorescent carbon dots (LCDs) in a partitioned manner through a template method. L is synthesized through diazo coupling reaction, and obvious yellow-purple color gradation change is generated when L is combined with Fe < 3 + > to form a 1: 1 complex; the LCDs are synthesized through a two-step hydrothermal method, and blue fluorescence (lambda max =-440 nm) of the LCDs can be quenched by Fe < 3 + > concentration (1.0-1000 M). In the double-signal cooperative detection mechanism, the colorimetric part is realized by combining RGB color analysis with smartphone image analysis, meanwhile, semi-quantitative visual discrimination is supported, and the distinguishable concentration of naked eye colorimetric reaches 10M; and the fluorescence part realizes Fe < 3 + > detection (the detection range is 10-20 mM) based on a quenching effect. The test paper can be operated through a sample dropping or dipping method, and false positive is effectively avoided through double-signal cross validation. The composite test paper has excellent selectivity on Fe < 3 + >, and a novel portable solution is provided for detection of metal ions in an actual environment.

The invention discloses a calixarene-based azo polymer and a preparation method and application thereof, and the preparation method comprises the following steps: diazotizing 4, 4 '-(benzo [c] [1, 2, 5] thiadiazole-4, 7-diyl) diphenylamine in a solvent containing sodium nitrite and hydrochloric acid; adjusting the pH to be neutral, and adding a mixed solution of calixarene and sodium acetate for reaction to obtain the calixarene-based azo polymer. Calixarene with different cavity sizes and 4, 4 '-(benzo [c] [1, 2, 5] thiadiazole-4, 7-diyl) diphenylamine (BTD) are crosslinked through diazo coupling reaction, a series of novel calixarene-based azo polymers (MCAPs) are constructed, the MCAPs have excellent adsorption performance on iodine trianions (I3-) in water, and the MCAPs have important scientific significance and application value for promoting sustainable development of nuclear energy.

The present invention provides a nanosheet and a preparation method thereof and an application in a blended all-vanadium liquid flow battery membrane, belonging to the fields of two-dimensional nanomaterial preparation technology and all-vanadium liquid flow battery diaphragm technology. The present invention utilizes the auxiliary effect of a surfactant so that the water-oil two-phase monomers participating in the diazo coupling reaction at the microphase interface can be evenly distributed at the interface, so that the pores of the obtained porous organic polymer skeleton are more regular; in addition, the interface confinement effect of the water-oil two-phase will inhibit the growth of the diazo coupling reaction in the longitudinal direction, thereby obtaining a nanosheet material with a high specific surface area and two-dimensional properties. Due to the confinement effect of the narrow pores, the penetration of vanadium ions can be effectively inhibited, and the ion selectivity of the membrane can be improved. Moreover, because the nanosheet has a rich pore structure, it can not affect the transfer of protons, so that the blended all-vanadium liquid flow battery can obtain higher performance.

The invention belongs to the technical field of deuterated organic chemical synthesis, and particularly relates to a synthetic method of deuterated 4-bromodiphenyl-D9, which comprises the following steps: step 1, nitration reaction of deuterated bromobenzene: enabling the deuterated bromobenzene to react with mixed acid to obtain deuterated p-bromonitrobenzene-D4; step 2, reduction reaction of deuterated p-bromonitrobenzene: taking hydrazine hydrate and carbon powder as a reduction system, and reducing the deuterated p-bromonitrobenzene-D4 into deuterated p-bromoaniline; and step three, diazo coupling reaction of deuterated p-bromoaniline: carrying out diazo coupling reaction on deuterated p-bromoaniline and deuterated benzene to obtain the target product deuterated 4-bromodiphenyl-D9. The synthesis method is simple in process, high in purity and simple in post-treatment, the used raw materials are low in price and easy to obtain, the application of the deuterated biphenyl aromatic hydrocarbon as an intermediate in organic photoelectric synthesis is expanded, the problems of more byproducts, reduced deuteration rate, high cost and the like in a traditional process are solved, and the synthesis method is suitable for industrial production.

The application relates to the technical field of organic synthesis, and provides a preparation method of 4-[(2,4-diaminophenyl)azo]benzenesulfonic acid. The p-aminobenzenesulfonic acid, hydrochloric acid, sodium nitrite and a solvent are mixed, a diazotization reaction is carried out under strong acid conditions to generate a diazonium salt solution; the m-phenylenediamine, formaldehyde, sodium bisulfite and a solvent are mixed to generate 1,3-benzene di(iminomethyl sulfonic acid sodium) coupling solution; then the coupling solution is slowly added into the diazonium salt solution, and stirring is carried out at room temperature overnight; and after alkaline hydrolysis and acidification, the target product is obtained. The diazo coupling reaction is adopted to successfully synthesize a 4-[(2,4-diaminophenyl)azo]benzenesulfonic acid compound, the reagent used in the method is cheap and easy to obtain, the operation is simple, the yield is high, and the method is suitable for industrial production.

The invention belongs to the technical field of biological materials, and particularly relates to silk fibroin-loaded hydrogel lipidosome with a transdermal delivery effect as well as a preparation method and application of the silk fibroin-loaded hydrogel lipidosome. The preparation method comprises the following steps: dissolving degummed silk in a neutral salt solution to obtain a silk fibroin solution, and dialyzing and filtering to obtain a silk fibroin aqueous solution; then carrying out diazo coupling reaction on the silk fibroin aqueous solution to obtain an azide functionalized silk fibroin aqueous solution; dissolving phospholipid and cholesterol in a solvent to obtain a mixed solution; adding the azide functionalized silk fibroin aqueous solution into the mixed solution, and carrying out ultrasonic emulsification to obtain an emulsion; the emulsion is sequentially subjected to reverse evaporation treatment, and gelated silk fibroin loaded liposome is obtained; and carrying out freeze drying on the gelated silk fibroin loaded liposome to obtain the silk fibroin loaded hydrogel liposome with a transdermal delivery effect.

The application belongs to the technical field of biological materials, and particularly relates to a silk fibroin-loaded hydrogel liposome with transdermal delivery effect and a preparation method and application thereof. The preparation method comprises the following steps: dissolving degummed silk in a neutral salt solution to obtain a silk fibroin solution, performing dialysis filtration to obtain a silk fibroin aqueous solution; then performing a diazo coupling reaction on the silk fibroin aqueous solution to obtain an azide-functionalized silk fibroin aqueous solution; dissolving phospholipid and cholesterol in a solvent to obtain a mixed solution; adding the azide-functionalized silk fibroin aqueous solution into the mixed solution to perform ultrasonic emulsification to obtain an emulsion; sequentially performing reverse evaporation treatment on the emulsion to obtain a gelled silk fibroin-loaded liposome; and performing freeze-drying on the gelled silk fibroin-loaded liposome to obtain the silk fibroin-loaded hydrogel liposome with transdermal delivery effect.