37results about "Preparation by nitrogen oxide-organic compound reaction" patented technology

A process for preparing a hydrocyanation catalyst comprising contacting a bidentate phosphorous-containing ligand with nickel chloride in the presence of a nitrile solvent and a reducing metal which is more electropositive than nickel the nickel chloride being introduced as an aqueous solution and the water being removed concurrently with the reduction reaction by azeotropic distillation.

The invention discloses an acrylonitrile production device and a method for controlling the temperature of a reactor thereof, wherein, the acrylonitrile production device comprises a GPC controller and a PID feeding control circuit, and the output end of the GPC controller is connected with the input end of the PID feeding control circuit. When the temperature control is performed, firstly, a GPC control algorithm is adopted to modify a preset value of feeding flow of a reactor, according to the preset temperature information and the actual temperature information of the reactor, to obtain an actual preset value of the feeding flow; then the feeding flow is adjusted through the PID algorithm to realize the control to the temperature of the rector. The method can ensure that the reactor has steady temperature control, steady change of an actuating mechanism, and long service life.

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 provides a preparation method for m-xylylenediamine. In the method, the m-xylylenediamine is converted into isophthalonitrile through ammoxidation; the obtained isophthalonitrile is extracted by using N-alkylpyrazole; after carboxylic acid is removed from extracted isophthalonitrile solution through resin, the isophthalonitrile solution enters a hydrogenation reactor for performing ahydrogenation reaction, to obtain a m-xylylenediamine reaction solution; and finally, the m-xylylenediamine with a high purity (99.9%) is obtained by rectifying and separating. The method has the characteristics of simple reaction flow, low energy consumption, simple operation, high m-xylylenediamine yield, high m-xylylenediamine purity and the like.

The invention discloses a method for preparing 2, 6-dichlorobenzonitrile, and relates to the technical field of production of chemically synthesized 2, 6-dichlorobenzonitrile. According to the method, 2, 6-dichlorotoluene is used as a starting material and chlorinated to prepare 2, 6-benzylidene chloride, the 2, 6-benzylidene chloride is hydrolyzed and quaternized to prepare a 2, 6-dichlorobenzonitrile crude product, and the 2, 6-dichlorobenzonitrile crude product is refined to obtain a 2, 6-dichlorobenzonitrile fine product. Production is easily controlled, raw material consumption is less, production cost is low, solid waste is decreased, emission of nitrogenous nitroso-group waste gas is reduced, and the method is an energy-saving, emission-reduction and environment-friendly industrial practical cleaning production technique.

The present invention relates to a process for preparing 4-chloro-3-hydroxybutanoic acid ester, an intermediate for preparing atorvastatin, in high purity and yield, by comprising the steps of 1) reacting epichlorohydrin of formula (2) with cyanide of formula (3) under the condition of pH ranging from 7 to 8, to form the 4-chloro-3-hydroxybutyronitrile of formula (4) and 2a) dissolving the 4-chloro-3-hydroxybutyronitrile of formula (4) in an alcoholic solvent and reacting it with hydrogen chloride, or 2b) reacting the 4-chloro-3-hydroxybutyronitrile of formula (4) in an alcoholic solvent saturated with hydrogen chloride, to form the 4-chloro-3-hydroxybutyronitrile acid ester of formula (I).

The invention discloses a preparation method for p-aminobenzamidine hydrochloride, and belongs to the field of drug synthesis. The preparation method comprises the following steps: taking p-aminobenzamidine as a starting raw material, and enabling the p-aminobenzamidine and hydroxylamine hydrochloride to generate nitrobenzonitrile; then, enabling the nitrobenzonitrile to react with ammonium salt to generate p-aminobenzamidine; carrying out acylation and reduction on the p-aminobenzamidine to obtain p-aminobenzamidine imidogen n-hexyl formate; finally, performing salifying on the p-aminobenzamidine imidogen n-hexyl formate and hydrogen chloride to obtain the p-aminobenzamidine hydrochloride. Compared with the prior art, the preparation method for the p-aminobenzamidine hydrochloride disclosed by the invention has the characteristics of being simple to operate, easy to control in reaction, low in production cost and the like, and has a very good popularization and application value.

The catalyst for synthesizing para-hydroxy-benzonitrile includes main catalyst and co-catalyst. The main catalyst has active matters MoO3, Cr2O3 and P2O5 in the atom ratio of Mo:Cr:P=1:1.3-10:15-75; and the co-catalyst has active matter of at least one of the oxide of Fe, Ti, Bi, Sb, Li, Na, K, Rb and Cs, and the atom ratio to Mo of 0.1-11. Using the catalyst of the present invention in ammoxidation process to synthesie para-hydroxy-benzonitrile has high product selectivity and yield, long catalyst service life, small ammonia ratio and excellent application foreground.

The invention discloses a production device for preparing 2, 6-dichlorobenzonitrile, and relates to the technical field of production of chemically synthesized 2, 6-dichlorobenzonitrile. The production device comprises an evaporator, a buffer tank, a hydrogen chloride recycling tank, a chlorination kettle, a first rectifying still and a hydrolysis quaternizing kettle. The production device is reasonable in design, convenient to control, less in raw material consumption and low in production cost, solid waste is decreased, emission of nitrogenous nitroso-group waste gas is reduced, and the production device is an energy-saving, emission-reduction and environment-friendly industrial practical cleaning production technique.

The invention relates to a high-stability fluid catalyst for producing acrylonitrile by propylene ammoxidation, which mainly solves the problem of poor stability of catalysts in the prior art. The high-stability fluid catalyst adopts silicon dioxide, aluminum oxide or a mixture thereof as a carrier and comprises a composition with the following chemical formula in atomic ratio: AaBbGecBafPrdBieMo12Ox, wherein A is at least one of Li, Na, K, Rb or Cs; and B is at least one of Ca, Mn, Fe, Co or Ni. The technical scheme solves the problem better, and can be used for industrial production of the acrylonitrile under the high propylene loading condition.

The invention discloses a preparation method of 4-bromo-2, 6-difluorobenzonitrile. In the preparation method, tetrahydrofuran, potassium tert butoxide, petroleum ether, 3, 5-difluorobromobenzene, DMF and n-butyllithium with the proportion of n-butyllithium: 3, 5-difluorobromobenzene, which is equal to 1.2:1 and the proportion of DMF: 3, 5-difluorobromobenzene, which is equal to1.6:1 are taken as raw materials to produce 4-bromo-2, 6-difluorobenzaldehyde, and methanoic acid, 4-bromo-2, 6-difluorobenzaldehyde and hydroxylamine hydrochloride with the weight ratio of the methanoic acid, the 4-bromo-2, 6-difluorobenzaldehyde and the hydroxylamine hydrochloride equal to 4:1:1.4 are taken as raw materials to prepare the 4-bromo-2, 6-difluorobenzonitrile. The preparation steps of the 4-bromo-2, 6-difluorobenzonitrile are as follows: A: the raw materials are added to a three-necked flask according to the proportion, and are heated and refluxed for 10 hours at normal pressure; B: a solvent is distilled at normal pressure, then corresponding volume of water is added to the system to continuously distill, and the 4-bromo-2, 6-difluorobenzonitrile is carried out; and C: the distilled aqueous solution is naturally cooled to the room temperature and is carried out suction filtration; a filter cake is washed with water to be neutral, and the product is obtained. The method for preparing the 4-bromo-2, 6-difluorobenzonitrile of the invention takes the 3, 5-difluorobromobenzene as a basic raw material which is cheap, and the whole process engineering is low in cost, so the 4-bromo-2, 6-difluorobenzonitrile is applicable to mass production. The preparation method does not adopt the hypertoxic potassium cyanide and strong corrosive substances such as sulfuric acid, bromine, and the like, which are adopted in the existing process, thus reducing the environmental pollution.

A method for producing an organic compound by making at least one of (A) a compound capable of generating free radicals and (B) an ester and a salt of nitrous acid have, in its ring structure, compositionally represented by the above formula (i) The nitrogen-containing cyclic compound of the skeleton is reacted in the presence of the ring compound, wherein X is one of an oxygen atom and an -OR group, and wherein R is one of a hydrogen atom and a hydroxyl protection group. Examples of nitrogen-containing cyclic compounds include cyclic imide compounds having a cyclic imide skeleton represented by the above formula (I), wherein n is one of 0 and 1; X is one of an oxygen atom and an -OR group species, and wherein R is one of a hydrogen atom and a hydroxyl protecting group.

The invention relates to a synthetic method of dichlorobenzonitrile, which is characterized in that dichlorobenzonitrile and oxammonium hydrochloride are resolved in an organic solvent, and the dichlorobenzonitrile is catalyzed and synthesized through a heteropoly salt catalyst, the reaction temperature is controlled to range from 80 to130 DEG C, and the reaction lasts for 8 to 12h. In the invention, cyanide is not used as raw materials, the method is simple and feasible, the product yield is high, the process flow is simple, the requirements of equipment are low, and the catalyst can be recovered for reutilization.

The present invention disclosed 3-substituted phenylamidine compounds of general formula (I), wherein R¹, R², R³, R⁴, R^4a, R^4b, A and E have the same meanings as defined in description. The present invention further discloses methods for their preparation and use of the compounds of general formula (I) as a crop protection agent.

Disclosed is a recovery method of a nitrile-based monomer including: supplying a feed stream including a nitrile-based monomer, a nitrogen compound, and water to a first distillation tower to separate the stream into a lower discharge stream and an upper discharge stream; condensing the upper discharge stream of the first distillation tower and supplying the condensed stream to a decanter to separate the stream into a water layer and an organic layer; supplying an organic layer stream discharged from the decanter to a second distillation tower to separate the stream into a lower discharge stream and an upper discharge stream; and splitting a part of the upper discharge stream from the second distillation tower and refluxing the split stream to the second distillation tower.

The invention provides a preparation method of 3, 4-dimethoxybenzonitrile, which comprises the following steps of adding 3, 4-dimethoxyphenyl acetone and nitrogen oxide into an organic solvent, and carrying out catalytic reaction by an iron catalyst under the protection of inert gas to obtain the 3, 4-dimethoxybenzonitrile. According to the method, 3, 4-dimethoxyphenyl acetone is used as a raw material, so that high yield can be realized at a relatively mild reaction temperature.