54 results about "O-nitrotoluene" patented technology

The invention discloses a method for preparing an age inhibitor 3100. In the method, paraaminophenol, aniline and o-nitrotoluene are taken as raw material for condensation reaction under the effect of organic sulfonic acid catalyst, the reaction temperature is 110 to 220 DEG C, water and ammonia produced by the reaction can be led out through azeotropic solvent continuously, after the reaction reaches an end point, the temperature is lowered to 100 to 140 DEG C, filtering is performed while hot, and filter liquor is distilled for removing impurities. The method provided by the invention has a high raw material conversion rate, the contents of the obtained effective components are high, the cost is low, the three wastes are less, and the method is suitable for industrial production.

The invention relates to a method for industrialized producing 2.6-dichlorobenzonitrile, adopting 6-chloro-o-nitrotoluene chloro-o-nitrotoluene as raw material to make chlorination reaction under the action of catalyst, then making cyanogenation reaction with formic acid and hydroxylammonium chloride, and refining again and again to obtain 2.6-dichlorobenzonitrile whose content is 99.8% above. The produced 2.6- dichlorobenzonitrile is a white powdery crystal, purity 99.8%-9995%, melting point 141.0 deg.C -144.0 deg.C, water ratio <=01%, and product yield up to 64%.

The invention relates to a process for preparing aromatic aldehydes, in particular a process for preparing o-nitrobenzaldehyde through bionic catalytic oxidation of ortho-methylnitro benzene, wherein metallic phthalocyanine, single nuclear metalloporphyrin or mu-oxy-double nuclear metalloporphyrin having the similar structure as the biological enzymes are selected as the catalyst for the disclosed process, whose dose is 0.2-1.0% weight of ortho-methylnitro benzene, and methyl alcohol is used as solvent, 0.8-3.0 MPa oxygen is let into 3.0-6.0 mol/L strong alkaline methyl alcohol solution, the reaction temperature is controlled between 25 deg. C to 60 deg. C, the reaction time being 6-48 hrs.

The invention discloses a preparation method of 2-nitrobenzyl bromide, and belongs to the technical field of chemical synthesis. According to the method, o-nitrotoluene, hydrobromic acid and hydrogenperoxide are taken as raw materials, under the initiation of catalysts, the 2-nitrobenzyl bromide is generated by conducting substitution reaction through a micro-channel reactor constantly; the 2-nitrobenzyl bromide is prepared through the micro-channel reactor, the operation is simple, the procedures are simple and the reaction time is greatly shortened.

The invention relates to an antiepileptic drug carbamazepine intermediate preparation method, in particular to a 2,2'-dinitrodibenzyl preparation method.The 2,2'-dinitrodibenzyl preparation method includes the steps of subjecting o-nitrobenzaldehyde and o-nitrotoluene serving as raw materials to addition reaction then substitution reaction with a bromination reagent, and debromination under the action of a reducing agent so as to obtain 2,2'-dinitrodibenzyl.The 2,2'-dinitrodibenzyl preparation method has the advantages of a novel synthetic route, conventional reaction steps, simple technologies, high yield, high purity, capability of avoiding high-pollution operating steps and suitability for industrial production.

The invention discloses a method for preparing 6-chloro-2-nitrotoluene. The method comprises the following steps of: throwing o-nitrotoluene into a reaction kettle; starting and stirring; adding a catalyst; heating; introducing chlorine gas at the temperature of between 25 and 85 DEG C, wherein tests show that the reaction is ended when the o-nitrotoluene content is 8 to 12 percent; cooling; discharging; and then performing rectification. In the preparation method, by properly selecting the catalyst on the basis of not changing the conventional mature technology, the proportion of the 6-chloro-2-nitrotoluene to 4-chloro-2-nitrotoluene serving as two isomers can be effectively improved, so that the 6-chloro-2-nitrotoluene content is about 65 percent, the production cost is reduced, the energy is saved and the method is suitable for industrial production.

The invention relates to a process for preparing aromatic aldehydes, in particular a process for preparing p-nitrobenzaldehyde through bionic catalytic oxidation of p-nitrotoluene, wherein metallic phthalocyanine, single nuclear metalloporphyrin or mu-oxy-double nuclear metalloporphyrin having the similar structure as the biological enzymes are selected as the catalyst for the disclosed process, whose dose is 0.1-1.0% weight of p-nitrotoluene, and methyl alcohol is used as solvent, 0.5-3.0 MPa oxygen is let into 0.7-2.8 mol/L strong alkaline methyl alcohol solution, controlling the reaction temperature to be 20-65 deg. C, the reaction time being 6-48 hrs.

The invention discloses a kind of precursor compounds 4-fatty sulfoamide-2-nitrobenzyl bromide which can form a vesicle and is photodegradable and a synthetic method, and belongs to the field of surfactants. The preparation method comprises adding o-nitrotoluene into chlorosulfonic acid at 0 DEG C, and reacting at 30-80 DEG C to generate 4-chlorosulfonyl-2-nitrotoluene; dissolving the obtained intermediate in a solvent, dropwise adding a long-chain primary amine or secondary amine, adjusting pH to 7-11, and reacting at 30-50 DEG C for obtaining 4-fatty sulfonamide-2-nitrotoluene, performing reduced-pressure concentration on the reaction solution, and performing pumping filtration and drying; and dissolving the product obtained in the above step in a solvent, adding an initiator, adding a brominating agent and reacting at 30-110 DEG C to obtain 4-fatty sulfoamide-2-nitrobenzyl bromide. The synthetic method is simple, the yield of each step of reactions is larger than or equal to 60%, the employed reaction eluant is petroleum ether and ethyl acetate, human body damage is relatively small, and petroleum ether and ethyl acetate are recoverable and reusable, and the synthetic method is friendly to environment.

The invention relates to a preparation process of 2-tolylhydrazine hydrochloride, which comprises the following steps of: firstly, carrying out a diazo reaction on o-nitrotoluene as an initial raw material to obtain benzenediazonium chloride; secondly, further carrying out a reducing reaction on the benzenediazonium chloride obtained in the first step under the action of a reducing agent to obtain a reduzate; and thirdly, carrying out a hydrolytic reaction on the reduzate obtained in the second step under the action of hydrochloric acid to generate the 2-tolylhydrazine hydrochloride. Particularly, in the second step, sodium metabisulfite is used as the reducing agent in the reducing reaction; and the reducing reaction is carried out under the conditions that the temperature is 15-25DEG C and the pH value is 7-9. According to the method, the production period can be shortened and the production cost is reduced while high yield is obtained.

The invention discloses a synthesis method of DPA. The method comprises the following steps: (1) adding methanol, o-nitrotoluene, a catalyst, concentrated sulfuric acid, distilled water into an autoclave, performing heating with stirring to 50 DEG C, evacuating air and then introducing hydrogen, controlling a pressure in the autoclave to 0.1 MPa, carrying out a reaction for 5 h, then performing suction filtration, distilling a filtrate to remove methanol, diluting a residual solution by adding water and then adjusting pH to be neutral with ammonia water, performing extracting with toluene, washing an organic phase with a dilute sodium hydroxide solution, and performing reduced pressure distillation on the organic phase to obtain 4-methoxy-2-methylaniline; and (2) adding 4-methoxy-2-methylaniline, phenol naphthalene, cyclohexanone, and the catalyst into an autoclave, replacing air with nitrogen, performing heating to 250 DEG C, controlling a pressure in the autoclave to 1 Mpa, performing cooling to room temperature after a reaction is completed, filtering a reaction solution, and performing reduced pressure distillation on a filtrate and collecting various fractions, wherein a latter fraction is DPA. The raw materials are cheap and easy to obtain, the operation is simple, the yield is high, the energy consumption is low, and the method has practical value and economic value, andis suitable for enterprise production.

The invention discloses a method for preparing methylaniline by reducing nitrotoluene through liquid phase continuous catalytic hydrogenation. The method comprises the following steps: S1, preparationstage: weighing o-nitrotoluene, m-methylnitrobenzene, p-nitrotoluene and a nano-catalyst, and enabling the addition mass ratio of the nitrotoluene to the methylaniline to be 4:10 and the addition amount of the nano-catalyst to be 10 percent that of the nitrotoluene; S2, start stage: feeding the weighed o-nitrotoluene, meta-methylnitrobenzene, p-nitrotoluene and nano-catalyst into a high-pressurereactor, and opening a pressure reducing valve and a pressure regulating valve of a hydrogen gas cylinder. The method for preparing the methylaniline by reducing the nitrotoluene through the liquid phase continuous catalytic hydrogenation, disclosed by the invention, has the advantages that methanol or ethanol as a solvent is replaced with the o-nitrotoluene, the meta-methylnitrobenzene and the p-nitrotoluene, so that loss in the reaction process is reduced, and easy explosion due to over-great internal pressure is prevented; in addition, a skeleton Ni is replaced with the nano-catalyst, so that the production cost of the material is reduced; the characteristics of cycle use and stability of the nano-catalyst are utilized.

The invention relates to a catalyst for preparing o-toluidine through catalytic hydrogenation of o-nitrotoluene and a preparation method of the catalyst. The catalyst takes metal Cu as an active component and takes modified SiO2 as a carrier. The active component Cu accounts for 15%-25% of the weight of the catalyst. In the preparation process of the catalyst, silica gel is pretreated, so that theprepared catalyst is regular in appearance, high in strength and not easy to crush. The active component copper is impregnated on silica gel in the form of a copper-ammonia complex in an alkaline atmosphere to form a Cu-Si coalition structure, thereby enhancing the thermal stability and carbon deposition resistance of the catalyst, and increasing the one-way service cycle of the catalyst to 8 hours or above. According to the method disclosed by the invention, the pore structure of the catalyst is improved, the proportion of the pore size of 2-15nm reaches more than 80%, the active component is highly dispersed on the carrier, and the conversion rate and selectivity of the catalyst reach more than 99.9%.

The invention discloses a method for synthesizing o-nitrophenylacetic acid. Absolute ethyl alcohol, Pt-MgO-CNTs, metal sodium, o-nitrotoluene, diethyl oxalate, hydrogen peroxide and H2PtCl6 are used as main raw materials, the synthesis process adopts the o-nitrotoluene and diethyl oxalate to be subjected to condensation reaction to obtain the o-nitrophenylacetic acid under the action of the catalyst Pt-MgO-CNTs, the separation method of steam distillation is replaced by vacuum distillation, the reaction time is greatly shortened, and the separation effect is significantly enhanced. The optimummaterial ratio, the temperature of oxidation reactions and the temperature and time of condensation reactions are optimized by a large number of experiments, and the yield is greatly improved.

The invention discloses a synthesis method of benzocaprolactam. The synthesis method comprises the following steps: S1, using o-nitrotoluene as a raw material, and carrying out a condensation reactionon the o-nitrotoluene and an acrylate under catalysis of an alkali to obtain o-nitrophenylbutyric acid or o-nitrophenyl butyrate; and S2, reducing nitro of the o-nitrophenylbutyric acid or o-nitrophenyl butyrate, and performing ring closing to obtain a target product, wherein nitro of the o-nitrophenylbutyric acid or o-nitrophenyl butyrate is reduced to obtain amino. According to the synthesis method, cheap chemical products are used as initial raw materials, so that cost is low; post-treatment operation is simple, and a qualified product can be obtained through a rectification mode or simplemodes such as extraction, crystallization, filtration and the like, so that industrial production is easy to realize.

The invention relates to a method for preparation of o-nitrobenzoic acid by catalytic oxidation, and the method comprises the following steps: adding a solvent, o-nitrotoluene, catalyst MnO2 and RuO4 into a high pressure reactor, introducing oxygen, reacting 5 to 15 hours at 100-150 DEG C under 0.1-2MPa, and after the reaction, filtering the catalyst, extracting, washing with water, and distilling to recover the solvent to obtain the o-nitrobenzoic acid. The filtered catalyst can be recycled.

The invention discloses a synthesis process of a pyraclostrobin intermediate o-nitrobenzyl bromide. The synthesis process comprises the following steps of: adding chlorobenzene, a hydrobromic acid solution and a catalyst into a reaction kettle, and performing heating; dropwise adding o-nitrotoluene and a hydrogen peroxide solution into the reaction kettle at the same time, and continuously carrying out heat preservation reaction for 2 hours; adding concentrated sulfuric acid and zinc powder into the reaction kettle in sequence, controlling the temperature to be 85-90 DEG C, and keeping the temperature for 1 hour; and standing for layering, separating out a lower organic phase, sampling and analyzing to obtain the o-nitrobenzyl bromide. The content of the o-nitrobenzyl bromide obtained through the synthesis process of the o-nitrobenzyl bromide is 75% or above, the content of the by-product dibromine is 0.5% or below; compared with an old process, the synthesis process has the advantages of being high in yield and few in by-product; and additional equipment is not needed in the synthesis process, the process operation is simple, and economic benefits are high.