49 results about "2-Methoxyethanol" patented technology

An improved synthesis method for preparation of iodixanol, and a purification process through macroporous adsorption resin chromatographic column and recrystallization are provided. The synthesis method relates to dimerization of 5-acetamido-N, N'-bis(2,3-dihydroxypropyl)-2,4,6- triiodo-isophthalamide (compound A) to prepare iodixanol, wherein excessive side reactions such as alkylation are effectively inhibited by controlling the pH of the reaction mixture with a boron-containing acidic substance or salts thereof such as boric acid. In this way, the conversion rate of compound A to iodixanol is 85-90%. The iodixanol crude product is purified by a macroporous adsorption resin chromatographic column, obtaining iodixanol product with recovery of 90-95% and purity of 96-98%. The iodixanol crude product is recrystallized in mixed solvent containing 2-methoxyethanol, obtaining iodixanol product with recovery of 90-95% and purity of greater than 99%.

The invention relates to a preparation method for a barium titanate / graphene composite nanometer material, and the method employs a wet chemical reaction process. The preparation steps comprise: taking 2-methoxyethanol as a solvent dissolving a titanium ion, utilizing ammonia water as a precipitating agent to precipitate titanium ion, adding an aqueous solution of graphene oxide, and fully mixing; utilizing a deionized water solution of barium acetate as a barium source, and taking a mixed solution of ethylenediamine and ethanolamine as a solvent; and finally utilizing a mineralization agent potassium hydroxide to promote crystallization, and performing hydro-thermal reaction to obtain the barium titanate / graphene nanometer powder. The preparation method is simple in process, easy to control, free of pollution and low in cost, and the prepared barium titanate / graphene composite nanometer material is high in purity and good in crystallinity.

The invention relates to a preparation method of bromfenac sodium. The preparation method comprises the following steps of (a) reacting a compound represented by a formula (V) with an electrophilic substitutional reagent in the presence of N,N-dimethylformamide or dimethyl sulfoxide to obtain a compound represented by a formula (IV), (b) adding the compound represented by the formula (IV) into 2-methoxyethanol, adding phosphoric acid and carrying out acid hydrolysis to obtain a compound represented by a formula (III), (c) hydrolyzing the compound represented by the formula (III) with sodium hydroxide, extracting with dichloromethane and adding acetic acid to neutralize to obtain a compound represented by a formula (II) and (d) in the presence of an organic alcohol solvent, adding a sodium hydroxide solution, hydrolyzing the compound represented by the formula (II) to form a salt, adding the organic alcohol solvent, cooling and crystallizing to obtain bromfenac sodium. According to the preparation method disclosed by the invention, the reaction yield of the intermediate (IV) and the quality of the product are improved, high-purity bromfenac sodium can be obtained just by virtue of crystallizing with the organic alcohol solvent, the good environmental benefit is achieved and the generation of bromfenac sodium polymer impurity is reduced.

The invention relates to a bromfenac sodium preparation method. The preparation method comprises specific steps as follows: indole reacts under the action of DMSO (dimethylsulfoxide) to produce 3-bromoindole; 3-bromoindole is added to 2-methoxyethanol, acid is added for hydrolysis, and 2-indolinone is obtained; boron trichloride is added to methylbenzene, a methylbenzene mixed solution of p-bromobenzonitrile and 2-indolinone is added dropwise, aluminum chloride is then added, acid is added, a reaction is performed, and 7-(4-bromobenzoyl)-1,3-dihydro-indol-2-one is obtained; hydrolysis is performed with an alkaline solution, acid is added for neutralization, and bromfenac is obtained; ethanol is added to bromfenac, bromfenac and a sodium hydroxide solution form salt, the salt is cooled and subjected to recrystallization, and bromfenac sodium is obtained. Compared with the prior art, the synthetic route is short, high-purity bromfenac sodium can be prepared, the quality meets the latest standards of pharmacopoeia, industrial production is facilitated, and the method can provide powerful guarantee for industrial production of bromfenac sodium and intermediates of bromfenac sodium.

The ether compound represented by formula (3) (where R represents an alkyl group having 1 to 6 carbon atoms) can be prepared by the following method, which includes: Step A: In 2-methoxyethanol, the formula (1 ) (where n represents an integer from 0 to 5, X represents a halogen atom, an alkyl group with 1 to 3 carbon atoms, cyano, nitro or trifluoromethyl) and a compound with 1 to 6 carbon atoms Metal alkane thiolate reaction; step B: adding water and a hydrocarbon solvent having 5 to 8 carbon atoms to the reaction mixture obtained in step A, and separating the organic layer; step C: from the reaction mixture obtained in step B The solvent is distilled off in the organic layer to prepare bis(alkylthiomethyl) ether; and step D: the bis(alkylthiomethyl) ether obtained in step C is mixed with 2- Cyanoethanol reacts with halogenating agents.