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49 results about "Ortho-nitrotoluene" patented technology

2-Nitrotoluene or ortho-nitrotoluene is an organic compound with the formula CH 3 C 6 H 4 NO 2. It is pale yellow liquid that is a versatile intermediate in the production of various dyes. It is pale yellow liquid that is a versatile intermediate in the production of various dyes.

A preparing method of 2-nitrobenzaldehyde

The invention discloses a preparing method of 2-nitrobenzaldehyde. 2-nitrotoluene is adopted as a raw material and is brominated with bromine under catalytic function of azo-bis alkyl nitrile to generate 2-nitrobenzyl bromide and hydrogen bromide. The 2-nitrobenzyl bromide is hydrolyzed under catalytic function of an aqueous carbonate solution to generate 2-nitrobenzyl alcohol. The 2-nitrobenzyl alcohol is oxidized with hydrogen peroxide under catalytic function of sodium hydroxide to generate the objective compound, namely the 2-nitrobenzaldehyde. A hydrogen peroxide oxidation manner is adopted by the method, thus improving cleanliness of industrial preparation reactions, and reducing environment pollution. Oxidation is catalyzed by adopting the inorganic solid alkali catalyst and no metal organic complex catalyst is used, thus improving reaction stability and greatly reducing the cost of industrial preparation. An azo-bis alkyl nitrile solid catalyst in place of a peroxydicarbonate liquid catalyst is adopted to catalyze the bromination, thus improving reaction operation safety of industrial preparation. The method increases the product yield. The yield of the method is increased by about 5% than that of traditional industrial methods at present. The total yield can reach 77% and product purity is higher than 99%.
Owner:NANJING UNIV OF SCI & TECH

Method for synthesizing substituted indole compounds through one-pot method

The invention relates to a synthesis method of substituted indole compounds, and particularly relates to a method for synthesizing substituted indole compounds through a one-pot method. The method comprises the following steps: under alkaline and anaerobic conditions, reacting ortho-nitrotoluene derivatives and N,N-dimethylformamide dimethyl acetal or triethyl orthoformate used as raw materials in an organic solvent; and then, adding a reducer, and performing reduction and cyclization reaction to obtain indole derivatives, wherein R is a monosubstitution or polysubstitution located on site 4, 5, 6 or 7; and the R substituent is hydrogen, alkyl, substituted alkyl, alkoxy, amino or halogen atom. According to the invention, a one-pot method is adopted; the conventional and readily accessible ortho-nitrotoluene compounds are directly used as raw materials for reaction; separation and purification of intermediate compounds are not required; and the indole derivatives can be synthesized through the one-pot method by effectively controlling the reaction conditions, the charging sequence and the charging ratio. According to the invention, the technological operation procedure is simplified, the reaction time is shortened, the cost is saved, the total yield is improved, and better production and practical values can be achieved.
Owner:YANTAI INST OF COASTAL ZONE RES CHINESE ACAD OF SCI

Method for by-producing steam in ortho-nitrotoluene separation process

The invention relates to a method for by-producing steam in the ortho-nitrotoluene separation process. The method comprises the steps of feeding a material into an adjacent rectifying column for rectifying; enabling the product vapor phase to flow from the top of the adjacent rectifying column into a condenser to be condensed; transferring the non-condensed product vapor phase into a sub-cooler for cooling; feeding the cooled product and the product condensed by the condenser into a reflowing tank; enabling the non-condensed trace vapor phase to flow from the sub-cooler into a vacuum collecting system through a vacuum buffering tank to be discharged; transferring part of the material from the reflowing tank into the adjacent rectifying column through a reflowing pump for reflowing, and processing the rest part of the material by cooling and then feeding into a product storage tank, wherein the product before being fed into the product storage tank is cooled through a soft water preheater, the soft water is preheated at the same time, then the preheated soft water enters a steam drum, saturated water in the steam drum enters the condenser to be used as a refrigerant medium, and the produced saturated steam is returned to the steam drum and then enters a steam pipe network after gas-liquid separation. The method is simple in process, the latent heat produced by cooling the product can be effectively utilized to produce steam, and therefore, the cost is decreased, the energy is saved, and the environment is protected.
Owner:QINGDAO UNIV OF SCI & TECH +2

Device for continuous preparation of o-nitrobenzyl bromide and preparation method thereof

The invention relates to a device for continuous preparation of o-nitrobenzyl bromide and a preparation method thereof. The device mainly comprises a tubular reactor, three storage tanks, three corresponding metering pumps, an efficient mixer and a receiving tank. The storage tanks are connected to the efficient mixer through pipelines. The metering pumps are distributed on the connecting pipelines of the corresponding storage tanks and the efficient mixer. The efficient mixer is successively connected to the tubular reactor and the receiving tank. A light source is arranged above the tubularreactor. A temperature measuring instrument is arranged in the tubular reactor. The preparation method comprises the following steps: raw materials including ortho-nitrotoluene, liquid bromine and water enter the mixer respectively through the three metering pumps to be uniformly mixed; the mixture then enters a pre-insulated tubular reactor to react under illumination; the reaction product entersthe receiving tank after the reaction, followed by standing; and an organic layer is taken, and an organic solvent is removed to obtain the product. The preparation method of o-nitrobenzyl bromide isconvenient to operate; the post-treatment is simple; the product has good yield and high purity, and is suitable for industrial production.
Owner:ZHEJIANG UNIV OF TECH

Method for preparing ortho-hydroxybenzoic acid by catalyzing and oxidizing ortho-nitrotoluene with metalloporphyrin and metal salt compound as catalyst

The invention relates to a method for preparing ortho-hydroxybenzoic acid by catalyzing and oxidizing ortho-nitrotoluene with a metalloporphyrin and metal salt compound as a catalyst. The method comprises the following steps of: introducing the oxygen of 0.5-2.5Mpa into the aqueous ethanol of 0.5-2.5mol/L sodium hydroxide by taking the aqueous ethanol comprising 50-95% by volume of ethanol as a solvent and taking the compound of a metalloporphyrin and a metal salt as a catalyst, or the compound of any two or three of a metalloporphyrin of formula I, a metalloporphyrin of formula II and a metalloporphyrin of formula III as a catalyst, or the compound of a metalloporphyrin of formula I and a metalloporphyrin of formula I or a metalloporphyrin of formula II and a metalloporphyrin of formula II or a metalloporphyrin of formula III and a metalloporphyrin of formula III as a catalyst, and carrying out reaction at the temperature of 35-55 DEG C for 1-6 hours to obtain the ortho-hydroxybenzoic acid, wherein the concatenation of the metalloporphyrin is 5-50ppm, and the concentration of the metal salt is 5-200ppm. The method provided by the invention has the advantages of high target product yield, short reaction time, small use amount of the alkali and low toxicity of the solvent. Due to the adoption of the method, the resource can be saved effectively, the pollution to the environment can be reduced, and the purposes of comprehensively saving energy and reducing emission can be achieved.
Owner:BEIJING UNIV OF TECH

Method for preparing methylaniline by continuous catalytic hydrogenation reduction of nitrotoluene through liquid phase

The invention discloses a method for preparing methylaniline by continuous catalytic hydrogenation reduction of nitrotoluene through a liquid phase. The method comprises the following steps that: S1,the preparing stage: ortho-nitrotoluene, meta-methylnitrobenzene, paranitrotoluene and a nano-catalyst are weighed, the mass ratio of nitrotoluene to methylaniline is 4:10, the addition quantity of the nano-catalyst is 10% of the addition quantity of the nitrotoluene; S2: the starting stage: the well weighed ortho-nitrotoluene, meta-methylnitrobenzene, paranitrotoluene and the nano-catalyst are added into a high pressure reaction kettle, and a hydrogen steel cylinder reducing valve and a pressure regulating valve are opened. According to the method for preparing the methylaniline by continuouscatalytic hydrogenation reduction of the nitrotoluene through the liquid phase, the ortho-nitrotoluene, the meta-methylnitrobenzene and the paranitrotoluene replace a solvent methyl alcohol or ethylalcohol, the loss in the reaction process is reduced, the explosion easily caused by the excessively large internal pressure is prevented, meanwhile, the nano-catalyst replaces a skeleton Ni, the costof the material is reduced, and the characteristics of recycling and stability of the nano-catalyst are used.
Owner:麻城市天恒商贸有限公司

Preparation method of high-activity anti-sulfur-poisoning palladium carbon catalyst

The invention discloses a preparation method of a high-activity anti-sulfur-poisoning palladium carbon catalyst. The preparation method includes the following steps: step 1, adding activated carbon into hydrochloric acid for cooking, performing filtering, adding solids obtained by filtration into nitric acid for cooking, and performing filtering and washing to obtain the acid-treated activated carbon; step 2, adding the acid-treated activated carbon into a modifier solution, and stirring the solution to obtain paste; step 3, adding the paste into an assistant metal salt solution, and stirringthe solution to obtain an activated carbon solution loaded with assistants; step 4, adding the activated carbon solution loaded with the assistants into a palladium chloride solution, adjusting the pH, stirring the solution to obtain a palladium suspension; step 5, reducing and filtering the palladium suspension, washing solids obtained by filtration, and centrifuging and spin-drying the solids toobtain the high-activity anti-sulfur-poisoning palladium carbon catalyst. The preparation method has the advantages that metal on the carrier surface of the obtained palladium carbon catalyst is highly dispersed, and high catalytic activity and anti-sulfur stability in hydrogenation of nitrobenzyl aniline and ortho-nitrotoluene are achieved.
Owner:XIAN CATALYST NEW MATERIALS CO LTD
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