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

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 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.

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 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 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 present invention disclosed 3-substituted phenylamidine compounds of general formula (I), wherein R1, R2, R3, R4, R4a, R4b, 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.

A method for producing a homocyclic or heterocyclic compound includes reacting a compound of formula (I) with a compound of formula (II) in presence of a base:In formula (I), B is an unsaturated moiety selected from substituted or unsubstituted vinylene, ethynylene, aryleneethynylene, substituted or unsubstituted arylenevinylene, and a combination thereof, the vinylene or arylenevinylene has n (=0, 1 or 2) substituent(s) R2, G is an electron-withdrawing group, R1 is hydrogen or a substituent, and two of R1, R2 and G may joint together to form a ring. In formula (II), R3 and R4 are independently hydrogen or a substituent, R5 is an electron-withdrawing group, and two of R3, R4 and R5 may joint together to form a ring. The conjugate acid of the base has a pKa in the range of 1 to 15.