47 results about "P-nitrobenzyl alcohol" patented technology

The invention relates to a preparation method of panipenem. Firstly, methyl acetoacetate and p-nitrobenzyl alcohol are taken as raw materials to prepare panipenem parent nucleus by six steps of reactions: ester exchange reaction, diazo reaction, enolization reaction, substitution reaction, hydrolysis reaction and ring closing reaction; then, (3R)-3-hydroxy-pyrrolidine hydrochloride, nitrobenzyl chroformate ester are taken as raw materials to prepare panipenem side chain by amidation reaction, sulfonylation reaction, nucleophilic substitution reaction and saponification reaction; finally, the prepared panipenem parent nucleus and panipenem side chain are in butt joint by condensation and are subjected to catalytic hydrolysis and imidization to obtain panipenem. The preparation method of panipenem features simple operation, mild reaction condition, friendly environment, high yield, good product purity, low cost and better industrialized production prospect.

The invention discloses a cost-saving preparation method of p-nitrobenzyl alcohol. The key points of the technical scheme are as follows: according to the cost-saving preparation method of the p-nitrobenzyl alcohol, p-nitrotoluene is taken as a starting raw material and reacts with chlorine gas to obtain p-nitrobenzyl chloride, and then the p-nitrobenzyl chloride is hydrolyzed in an alkaline solution to obtain p-nitrobenzyl alcohol. Compared with the prior art, the cost-saving preparation method of the p-nitrobenzyl alcohol has the following beneficial effects: the reaction system is simple and the raw material is cheap and easily available; the preparation cost is low and no hazardous waste is generated, so that the preparation method accords with the green production ideal; the cost-saving preparation method is simple in process, simple and convenient to operate, short in reaction time, high in efficiency and suitable for large-scale production.

The invention belongs to the technical field of fine chemical engineering. The invention relates to a preparation method and application of an adjustable metal organic cage compound for efficient selective catalytic reduction of nitrobenzaldehyde. According to the preparation method, M<2+> in a transition metal salt is used as a node and L is used as a ligand for reaction to prepare the metal organic cage compound, and the synthetic route is as follows: M<2+> + L- to M-L; wherein the ligand L is selected from H2FPB; the transition metal salt is selected from one of ferrous perchlorate, cobalttetrafluoroborate, nickel perchlorate or zinc tetrafluoroborate. The metal organic cage compound prepared by the method is low in raw material price and high in yield, and the obtained compound is stable in chemical property and easy to put into practical application. As a target compound M-FPB, the adjustable metal organic cage compound shows that the selectivity of the compound M-FPB can reach 99% in the aspects of reduction of p-nitrobenzaldehyde to prepare p-nitrobenzyl alcohol, one-step synthesis of cinnarizine by reduction catalysis of cinnamyl aldehyde and reduction of p-nitrobenzaldehyde to prepare p-aminobenzaldehyde.

The invention provides a microminiature rapid charging special-purpose aluminium electrolytic capacitor which comprises a shell, a core bag and a rubber plug. The core bag is sealed in the shell through the rubber plug. The core bag contains electrolyte which comprises a solvent, an inorganic acid ammonium salt, an organic acid ammonium salt, and a hydrogen elimination agent. The inorganic acid ammonium salt is ammonium borate or ammonium pentaborate or the mixture of the ammonium borate or the ammonium pentaborate. The organic acid ammonium salt comprises one or more of ammonium sebacate, ammonium azelate, diammonium phthalate, and dodecyl ammonium carboxylate. The hydrogen elimination agent comprises one or more of a p-Nitrobenzyl alcohol, a p nitroanisole and p-nitrobenzoic acid. The conductivity of the electrolyte in the invention is between 2.4 ms/cm to 2.8ms/cm, the ESR value of a product can be effectively reduced, thus the ripple resistance and lightning strike resistance ability of the product are improved greatly, the flash fire voltage is above 490V, in a condition of high voltage, the breakdown of electrolytic paper caused by flash fire of the electrolyte does not appears, and thus the voltageproof performance of the product is ensured.

The invention provides a process for synthesizing 4-Nitrobenzyl chloroformate, which comprises reacting trichloromethyl chloroformate or bis(trichloromethyl)carbonate with p-nitrobenzyl alcohol at -40-20 deg C under the action of acid-binding agent, finally carrying out post-treatment to obtain the outcome yield.

The invention relates to a method for synthesizing mono-4-nitrobenzyl malonate. The method comprises the steps of adding para-nitrobenzyl alcohol, malonic acid or malonate and a reaction solvent to a reaction flask at a mol ratio of 1: (1-10): (10-50); heating in a water bath until being balanced; adding lipase and a water absorbent to the reaction flask at a mol ratio of (0.1-1): (0-100) with the para-nitrobenzyl alcohol; controlling temperature at 30-50 DEG C, reacting for 10-48 hours, filtering to remove the lipase to obtain a reaction solution, and carrying out reduced pressure distilling on the reaction solution to remove the solvent, to obtain reaction residue; adding a mixing solution of an organic solvent and a salt solution to the reaction residue, stirring and layering, acidifying an obtained water phase, carrying out suction filtering and drying to obtain the mono-4-nitrobenzyl malonate. The method is easily available in raw materials, few in reaction step, moderate in reaction condition, few in side product, and simple and convenient to operate; the method, because the adopted organic solvent can be recycled, is low in environmental impact, simple in post-treatment, relatively high in production purity and yield, and suitable for industrial production.

The present invention relates to the technical field of electrolytes, in particular to a high-sparking and anti-lightning electrolyte for an aluminum electrolytic capacitor and a preparation method therefor. The electrolyte comprises the following raw materials in parts by weight: 1.5-2.5 parts of ammonium dodecanedioate, 0.8-1.2 parts of ammonium sebacate, 5-9 parts of sorbitol, 4-6 parts of boracic acid, 4-6 parts of diethylene glycol monobutyl ether, 1-2 parts of polyvinyl alcohol, 0.4-0.6 part of p-nitrobenzyl alcohol, 0.1-0.3 part of ammonium hypophosphite, 6-10 parts of ethylene glycol nano silica sol and 60-80 parts of glycol. The electrolyte is prepared by means of interaction among the raw materials and by strictly controlling a weight proportion of the raw materials; the sparking voltage of the prepared electrolyte can reach 590 V and the conductivity rate of the prepared electrolyte can reach 0.5 ms/cm; and the electrolyte has good electrochemical properties, has the advantages of high sparking voltage, lightning resistance and the like, and can be applied to manufacturing of the aluminum electrolytic capacitors.

The present invention relates to the technical field of electrolytes, in particular to a high-sparking and long-service-life electrolyte for an aluminum electrolytic capacitor and a preparation method therefor. The electrolyte comprises the following raw materials in parts by weight: 3-5 parts of ammonium sebate, 1-2 parts of ammonium pentaborate, 1-2 parts of sorbitol, 1.5-2.5 parts of ammonium dodecanedioate, 8-12 parts of a sparking boosting agent, 4-6 parts of branch-chain organic acid, 0.05-0.15 part of organic phosphate, 0.4-0.6 part of p-nitrobenzyl alcohol, 0.1-0.3 part of p-nitrophenol, 5-7 parts of ethylene glycol nano silica sol, 4-6 parts of Y-butyrolactone and 55-75 parts of glycol. The electrolyte is prepared by means of interaction among the raw materials; the sparking voltage of the prepared electrolyte can reach 535 V and the conductivity rate of the prepared electrolyte can reach 1.8 ms/cm; and the electrolyte has good electrochemical properties, has the advantages of high sparking voltage and long service life, and can be applied to manufacturing of the aluminum electrolytic capacitors.

The invention provides protected meropenem synthesized under simple conditions. In the invention, a compound (I) is reacted with mono-4-nitrobenzyl malonic acid ester and magnesium chloride to form a compound (II) product; the compound (II) is diazotized to form a compound (III) product; the compound (III) is dehydrated by methanesulfonic acid to obtain a compound (IV) product; the compound (IV) is cyclized to form a compound (V) product, and 4-dimethylaminopyridine, diphenyl chlorophosphate and N,N-diisopropylethylamine are added in turn to participate in reactions to form a product (VI) product; and N,N-diisopropylethylamine and (2S,4S)-2-dimethylaminocarbonyl-4-thio-1-(p-nitrobenzyloxycarbonyl)pyrrolidine are added to participate in a reaction to obtain a compound (VII) product. The method has the advantages that: the cost as well as 'waste gas, liquid and solid' are reduced, the operation is convenient, and the post-treatment is simple; and the total molar yield of the six-step reactions is more than or equal to 74 percent, so the method is easy to industrialize.

The invention provides a preparation method of p-nitrobenzyl 2-diazoacetoacetate, wherein, the p-nitrobenzyl 2-diazoacetoacetate is made by two-step reaction. The preparation method has the advantages of simplified processing steps, easy industrialized production, lowered production cost, improved product quality and higher yield, wherein, by taking nitrobenzyl alcohol as a standard, the total mol yield reaches more than or equal to 95%, and the purity of the product compound (IV) reaches more than or equal to 99.5%.

The invention provides a method for preparing p-nitrobenzyl alcohol propandioic acid monoester through double-enzyme catalysis. The method comprises the step of performing joint catalysis on 2-cyanoacetic acid-(4-nitrobenzophenone) methyl ester serving as a matrix by using alcaligenes faecalis-derived nitrilase and alcaligenes faecalis-derived amidase. The method provided by the invention is highin product yield, mild in reaction condition, low in environmental pollution and applicable to industrial production, and a small number of byproducts are produced.

The invention discloses a preparation method of magnesium mono-p-nitrobenzyl malonate. The preparation method comprises following steps: 1) 1-hydroxymethyl-4-nitrobenaene and malonic acid are added into a solvent, and the solution is subjected to esterification at a low temperature and in the presence of a catalyst; 2) the temperature of the reaction system is increased to 60 to 80 DEG C so as to realized crystal transition of products, and obtain mono-p-nitrobenzyl malonate; and 3) mono-p-nitrobenzyl malonate obtained in step 1) and magnesium chloride are added into water for reaction, and the reaction product is subjected to recrystallization, centrifugal separation and drying process so as to obtain magnesium mono-p-nitrobenzyl malonate. According to the preparation method, purity of intermediate mono-p-nitrobenzyl malonate is high, and can be more than 95%; yield of magnesium mono-p-nitrobenzyl malonate is high, and can be more than 80%; product clarity after dissolving is high; raw materials are easily available; reaction conditions are mild; operation is simple and convenient; by-products are few; production cost is low; and the preparation method is suitable for large-scaled industrialized production.

The invention relates to a nitrobenzy alcohol preparing method. Specifically, the nitrobenzy alcohol preparing method takes methyl nitrobenzene as the raw material to prepare nitrobenzy alcohol through processes of bromination, hydrolysis, refining and the like. During the processes, separation and purification of intermediates are saved, reaction solvent for both bromination and hydrolysis is water and can be repeatedly recycled and reused, and meanwhile, operation is simplified, the production cost can be saved, and emission of wastewater and waste gas can be reduced. The nitrobenzy alcoholpreparing method has the advantages of being simple in operation, low in investment, green, environmentally friendly and the like and is applicable to industrial production.

The invention relates to a method for preparing p-nitrobenzyl 2-diazoacetoacetate. The method takes p-nitrobenzyl alcohol and 2-diazoacetoacetate as raw materials, and ester exchange one-step reactionis carried out under the catalysis of acid or alkali to prepare the p-nitrobenzyl 2-diazoacetoacetate. The preparation method provided by the invention has the advantages of less investment, simplicity in operation, no highly toxic or explosive raw materials, greenness and cleanness and the like and is suitable for industrial production.

The invention discloses a preparation method of p-nitrobenzyl alcohol. The preparation method comprises the steps of with p-nitrobenzyl chloride (or bromine) as the raw material and water as a solvent, heating for hydrolysis under the catalysis of imidazole type iron liquid, and cooling for crystallization, so as to obtain a white product, namely p-nitrobenzyl alcohol. The raw material is easily available, and the preparation method good in atom economy, mild in reaction conditions, environment-friendly, simple, efficiency and suitable for industrial production.

The invention relates to the field of medical intermediate and discloses a preparation method of electronic-grade p-nitrobenzyl alcohol. The preparation method comprises the steps: dissolving p-nitrotoluene and bromine into water, adding the mixed solution into a reaction kettle, and adding an initiator for an initiation reaction at 45-55 DEG C until red is faded; dropwise adding hydrogen peroxide, adding the initiator according to a reaction condition, and carrying out a reaction at 80-85 DEG C after the dropwise adding operation is ended until the red is faded to obtain a bromide; adding liquid caustic soda and water, and keeping the temperature of 75-80 DEG C for 6-8h to obtain a hydrolysate; adding water and methyl alcohol, keeping the temprature of 60-65 DEG C for 1h, separating out an oil layer, carrying out cooling for crystallization, and when the temperature is reduced to 0 DEG C, carrying out centrifugation to obtain a crude product of p-nitrobenzyl alcohol; and adding methylbenzene, keeping the temperature of 70-75 DEG C for 30min, and carrying out pressure filtration, cooling and crystallization to obtain an electronic-grade p-nitrobenzyl alcohol product. A dichloroethane organic solvent is not needed, no hazards to operating personnel are caused, and the product conforms to the standard of an electronic-grade product.

The invention belongs to the field of electrochemistry, and discloses a capacitor electrolyte solution and a capacitor using the electrolyte solution. Ethylene glycol, ammonium formate, deionized water, organic high molecular compound, phosphate, tributylamine, polyvinyl alcohol, p-nitrobenzyl alcohol, carboxylic acid, phosphorous pentoxide and p-nitrobenzyl alcohol are mixed according to a certain mass ratio to prepare the capacitor electrolyte solution. Through addition of the organic high molecular compound, water molecules are fixed, the situation that water and the other harmful substances are in direct contact with dielectric film is prevented, improvement of saturated vapor pressure is inhibited, and hydration and corrosion are prevented. Parameters of the capacitor electrolyte solution are as follows, the conductivity (35 degrees) = 3.8 +/- 0.5 ms/cm, the pH value 6.5 +/- 1 and the broken voltage > 600 V. The capacitor electrolyte solution and the capacitor using the electrolyte solution have good electromagnetic compatibility and lightening resistance, can be widely applicable to the fields of mobile phone chargers and the like, and have very high economic value.

The invention relates to the field of medical intermediates, and discloses a preparation method of p-nitrobenzyl alcohol. The method comprises the steps of dissolving p-nitrotoluene and bromine into water, adding the mixed solution into a reaction kettle, adding an initiator at the temperature of 45-55 DEG C into the reaction kettle for an initiation reaction until red fades; dropwise adding hydrogen peroxide and adding the initiator as appropriate; after addition is finished, carrying out a reaction at the temperature of 80-85 DEG C until red fades so as to obtain bromides; adding sodium carbonate and water, and carrying out heat preservation for 6-8h at the temperature of 90-100 DEG C to obtain hydrolysate; adding water and methanol, carrying out heat preservation for 1h at the temperature of 60-65 DEG C, separating out an oil layer, cooling and crystallizing, and centrifuging when the temperature drops to 0 DEG C so as to obtain a crude p-nitrobenzyl alcohol product; adding methylbenzene, carrying out heat preservation for 30min at the temperature of 70-75 DEG C, carrying out filter pressing, cooling, and crystallizing to obtain the p-nitrobenzyl alcohol product. A dichloroethane organic solvent does not need to be used in the method, so that the method is harmless to an operator, and the purity of the product is higher.