13 results about "Alkyl nitrites" patented technology

The application provides a synthesis method of p-benzoquinone dioxime. The synthesis method comprises the following steps: (1) adding solid acid into an ethanol solution of phenol to obtain a mixed solution A, then vacuumizing and filling with inert gas; dissolving nitrite into ethanol, uniformly mixing to obtain an ethanol solution of nitrite, then vacuumizing and filling with inert gas; in an inert gas atmosphere, adding the ethanol solution of nitrite into the mixed solution A dropwise to perform nitrosation reaction, to obtain a reaction liquid B; in the inert gas atmosphere, adding an ethanol solution of hydroxylamine into the obtained reaction liquid B to perform oximation reaction; after the reaction is completed, filtering the obtained reaction liquid C, performing reduced pressure distillation on the obtained filtrate, and performing washing, filtering and drying on the obtained residual liquid of the reduced pressure distillation, to obtain p-benzoquinone dioxime. The method provided by the application reduces the occurrence of side reactions, improves the conversion rate of the reaction, and improves the yield and purity of p-benzoquinone dioxime.

The invention belongs to the technical field of organic synthesis, and particularly relates to a synthesis method of an isoxazoline compound. The preparation method comprises the following steps: dissolving a compound 1 and ethyl acrylate in dichloroethane, then adding tert-butyl nitrite, alkali and K2S2O8, in an air environment, irradiating with a 35 W blue LED light source and stirring at room temperature for 12 hours, after the reaction is completed, reducing pressure to remove a solvent, and then performing silica gel column chromatography on a crude product to obtain a product, namely the isoxazoline compound. The synthesis method provided by the invention avoids the problem of residue of a traditional metal catalyst, and provides a new normal form for green synthesis of the isoxazoline compound. As a key intermediate, isoxazoline can derive beta-lactam, beta-amino alcohol and other structures, and a new path is provided for complex molecule synthesis.

This invention provides a continuous process for producing ultrafine sodium azide, employing either System A or System B, including a nitrite ester synthesis section, a sodium azide synthesis section, and a gravity separation section. In the nitrite ester synthesis section of System A, the reaction temperature is -5℃ to 55℃, and the pressure is atmospheric pressure; the raw material alcohol includes methanol or ethanol. In the nitrite ester synthesis section of System B, the reaction temperature is -15℃ to 5℃, the pressure is atmospheric pressure, and the separation temperature is -5℃ to 55℃; the raw material alcohol includes methanol, ethanol, propanol, or isopropanol. This invention effectively enhances the mixing and transfer of materials under strong centrifugal force, thereby accelerating the reaction and separation speed. Even the azide reaction can proceed rapidly in the aqueous phase without a phase-transfer catalyst, reducing the reaction time from several hours to minutes. The residence time of materials in the equipment is extremely short, significantly shortening the production cycle.

The invention belongs to the field of medicine synthesis, and particularly relates to a preparation method of Remetirom (Remetirom). The preparation method comprises the following steps: reacting 2, 3, 6-dichloropyridazine, isobutyric acid, a catalyst, acid and a free radical initiator in a solvent to obtain an intermediate I; reacting the intermediate I with 4-amino-2, 6-dichlorophenol under the conditions of inert gas protection, catalyst and alkalinity to obtain an intermediate II; reacting the intermediate II with nitrous acid ester and N-cyanoacetyl ethyl carbamate under an acidic condition to obtain an intermediate III; and the intermediate III is subjected to a one-pot self-reaction in a carboxylate-carboxylic acid solvent to obtain the remetirol. The method provided by the invention has the advantages of short steps, low cost, mild reaction conditions, high total yield, suitability for industrial production and the like.

The application relates to the technical field of nitrite synthesis, and discloses a synthesis method and a synthesis device of alkyl nitrite. The synthesis method comprises the following steps: firstly, mixing gaseous nitric oxide and gaseous oxygen to obtain a mixture through a first reaction; and then, mixing the mixture with alkyl alcohol to obtain alkyl nitrite through a second reaction. The synthesis method greatly shortens the reaction time, increases the yield of alkyl nitrite, does not have a complicated post-treatment process and a large amount of by-product nitric acid, and is beneficial to cost saving and time saving.

This invention belongs to the field of organic synthesis, specifically relating to a green and efficient synthesis method for m-trifluoromethylacetophenone oxime. The specific steps are as follows: first, m-trifluoromethylaniline is added to a nonpolar solvent and reacts with nitrite ester under the action of an organic acid to generate a diazonium salt. Then, under the combined action of a phase transfer catalyst and a copper salt catalyst, it reacts with acetaldehyde oxime to generate m-trifluoromethylacetophenone oxime. After heating and filtering the copper salt catalyst, the mixture is cooled and crystallized to obtain m-trifluoromethylacetophenone oxime with a content of over 98% and a yield of over 90% based on m-trifluoromethylaniline. The above synthesis method generates less waste, has high atom utilization, high reaction yield, simple operation, strong process stability, and is easy for industrial production.

The invention discloses a cyclic regeneration method of a catalyst for preparing a 3, 3-dialkoxy propyl compound, which comprises the following steps: reacting an allyl compound with nitrite under the action of the catalyst, adding a reducing agent into the reaction system after the reaction is finished, filtering, and continuously rectifying the filtrate to obtain the 3, 3-dialkoxy propyl compound. The filter residues are oxidized by an oxidizing agent under the action of acid to generate a catalyst, and the catalyst is a bivalent palladium catalyst or a mixture of the bivalent palladium catalyst and a bivalent copper catalyst. An oxidizing agent and a reducing agent are added into a reaction system, so that the conversion of deactivation and reactivation of the catalyst is realized, coordination ions of the catalyst are provided by acid, and the cyclic regeneration of the catalyst is realized under the action of the oxidizing agent.

The invention belongs to the field of chemical synthesis, and particularly relates to a synthetic method of m-trifluoromethyl acetophenone, which comprises the following steps: 1, preparing nitrite through nitrosation reaction, 2, simultaneously dropwise adding the nitrite and m-trifluoromethyl aniline into an acetic anhydride substrate for reaction to directly obtain a product m-trifluoromethyl acetophenone feed liquid, and 3, carrying out post-treatment to obtain the m-trifluoromethyl acetophenone. And washing and rectifying to obtain the product. According to the scheme, the process route of preparing the m-trifluoromethyl acetophenone through diazotization, coupling and acidolysis reaction in the traditional process is broken through, the nitrite and the m-trifluoromethyl aniline react with the acetic anhydride under the action of the catalyst to directly synthesize the m-trifluoromethyl acetophenone in one step, the reaction steps are shortened, the generation of wastewater is greatly reduced, and the production cost is reduced. And the effect of reducing the cost is achieved.

The invention provides an amplified preparation method of a key intermediate of an estrogen receptor modulator, and belongs to the field of medical intermediates. The method comprises the following steps: by taking azetidine-3-one hydrochloride and 3-fluoro-1-halogenated propane as raw materials, reacting in the presence of alkali to obtain an intermediate 1; then carrying out reductive amination reaction on the intermediate 2 and 5-amino-2-methylpyridine to obtain an intermediate 2; reacting with nitrous acid ester in the presence of alkali to obtain an intermediate 3; and finally, reacting in the presence of acid to obtain the 5-((1-(3-fluoropropyl) azetidine-3-yl) amino) pyridinealdehydes. The method is simple and reliable in process and easy for industrial production; the generation amount of an isomer is reduced, and the reaction yield is improved.

The invention relates to a synthetic method of 2, 6-diethyl-4-methyl bromobenzene, which specifically comprises the following steps: reacting 2, 6-diethyl-4-methylaniline hydrobromide with phosphorus pentoxide and alkyl nitrite in the presence of an organic solvent. According to the method disclosed by the invention, water in the system can be fully removed, the generation of hydrolysis side reaction is avoided, the content of phenol impurities is reduced, meanwhile, the bromination reaction balance can be shifted rightwards, the bromination reaction yield is improved, and the production cost is greatly reduced. In addition, an alkali washing impurity removal step in an existing post-treatment procedure is avoided, impurities can be fully removed through simplified operation, the discharge amount of three wastes is reduced, and industrial production is facilitated.

The present invention relates to a novel method of synthesizing mononitrosylated and dinitrosylated propanediols and novel compositions and pharmaceutical formulations comprising said compounds. The method is carried out by reacting the corresponding non-nitrosylated propanediol with a source of nitrite, optionally in the presence of a suitable acid. Therein, when the source of nitrite is an organic nitrite, the reaction step is performed in a suitable organic solvent and when the source of nitrite is an inorganic nitrite, the reaction step is performed in a biphasic solvent mixture comprising an aqueous phase and a non-aqueous phase. The present invention further relates to methods of treating conditions in which the administration of nitric oxide (NO) has a beneficial effect, by administering said compounds, compositions or formulations.

The invention relates to the technical field of synthetic chemistry, in particular to a method for preparing 4-bromo-3-methoxyphenol. Comprising the following steps: (1) hydrolyzing a compound of formula I to generate a compound II; (2) reacting the compound shown in the formula II with toluene-4-sulfonyl chloride to generate a compound III; (3) reducing the compound in the formula III to generate a compound IV; (4) reacting the compound shown in the formula IV with nitrite or nitrite ester, and then reacting with a bromination reagent to generate a compound V; and (5) hydrolyzing the compound of formula V to generate a compound VI. According to the preparation method provided by the invention, the target product 4-bromo-3-methoxyphenol is efficiently prepared under mild conditions through the reaction steps of hydrolysis, substitution, reduction, bromination and the like, so that the problems of harsh oxidation reaction conditions, no reaction selectivity concern and high total molar yield of the original process are avoided, and the preparation method has the advantages of more controllable quality, high atom economy, low cost and the like. The process is stable, and production is easy. The synthesis route is shown in the specification.

Described is a process for the synthesis of mono- and bis-nitrosylated propanediols, as well as compositions and pharmaceutical formulations that includes the compounds. The process proceeds by reacting a corresponding propanediol that is not nitrosylated with a source of nitrite, optionally in the presence of a suitable acid. When the source of nitrite is an organic nitrite, reacting step is performed in a suitable organic solvent, and when the source of nitrite is an inorganic nitrite, the reacting step is performed in a bi-phasic solvent mixture comprising an aqueous phase and a non-aqueous phase. Also disclosed are methods of treating a condition wherein administration of nitric oxide (NO) has a beneficial effect by administering said compounds, compositions or formulations.