40results about How to "Reaction economy" patented technology

The invention discloses a method for preparing amino-acid ester. In the presence of an oxidant, the method adopts an amine compound and malonic ester as reactants, an iodide as a catalyst and sodium acetate as alkali; a product amino-acid ester is prepared through nucleophilic substitution in a polar solvent; the general formula of the chemical structure of malonic ester is shown in the decstiption; and the iodide is one of I2, TBAI, NIS and IBr. According to the method disclosed by the invention, the reaction activity of the catalyst is high, the reaction conditions are moderate, the application range of substrate is wide, the aftertreatment is convenient, the yield of the target product is high, the preparation process is simple and green and environment-friendly, and the raw materials are widely available.

The invention discloses a preparation method of an E-vinyl sulfones compound. The preparation method comprises the following steps: dissolving raw materials of olefin and thiophenol (thioalcohol) into a tetrahydrofuran solvent; then adding lodine pentaoxide and organic base DBU (1,8-diazabicyclo undec-7-ene); directly reacting for 12 to 16 hours under 60 to 80 DEG C; separating and purifying a coarse product after stopping reacting, thus obtaining the E-vinyl sulfones compound. The preparation method has the advantages that raw materials are simple and can be easily obtained, the price is cheap, the reaction requires no metal catalyst, metal pollution is avoided, the operation is simple and is free of harsh conditions of water free, oxygen free and the like, the adaptive range of a substrate is wide, the reaction stereoselectivity is high, the process conditions are stable, and a prepared product is easy to purify.

The invention relates to benzotriazole compounds and a preparing method thereof. o-phenylenediamine or an o-phenylenediamine compound n-butyl nitrite are adopted as reaction raw materials and are subjected to an intramolecular diazo-reaction at room temperature in a reaction solvent to obtain the corresponding benzotriazole compound. According to the method, the range of substrates is wide, reaction conditions are mild, after-treatment is simple, and a product yield and quality are high. A novel synthesis route and method for the benzotriazole compounds are developed. The benzotriazole compounds have good application potentials and research value.

The invention discloses an indolizine derivative and a preparation method thereof. A cheap copper compound is taken as a catalyst, a pyridine derivative, an olefinic derivative and a heavy nitrogen derivative are taken as reactants, and the catalyst and the reactants are subjected to cyclization reaction in a mixed solvent to obtain a product indolizine. The catalyst prepared with the method disclosed by the invention is cheap, can be easily obtained, is high in reaction activity, is moderate in reaction conditions, only needs to be carried out in the air, has a wide primer applicable range and is convenient in aftertreatment, and a final product can be obtained through simple column chromatography after reaction is finished. A target product has the advantages of high yield, simple preparation process, environment protection and wide raw material resource. The indolizine derivative conforms to the requirement and the direction of modern green chemistry development and has a potential industrial application value.

A process for producing chlorohydrins through reaction of a polyhydroxylated aliphatic hydrocarbon, such as glycerol, and/or an ester of polyhydroxylated aliphatic hydrocarbon with a chlorinating agent, which process realizes high reaction efficiency and economic advantage. The process for producing chlorohydrins comprises the steps of (A) reacting a polyhydroxylated aliphatic hydrocarbon and/or an ester of polyhydroxylated aliphatic hydrocarbon with a chlorinating agent and (B) bringing the thus obtained reaction mixture into countercurrent contact with a diffuser gas so as to cause at leasta potion of reaction product to be entrained by the diffuser gas and drawn out from the reaction mixture. Preferably, the process further comprises the step of (C) condensing at least a portion of the reaction product entrained by the diffuser gas.

The invention discloses a simple preparation method of isoxazoline. The simple preparation method is characterized in that a series of isoxazoline compounds are efficiently synthesized by using aldehyde, p-toluenesulfonhydrazide, olefin and tert-butyl nitrite as substrates, copper chloride as a catalyst and tetramethylethylenediamine (TMEDA) as alkali through the one-pot two-step method. The method has the advantages that the catalyst is cheap, reaction is economical, good substrate universality is achieved, the raw materials are easy to obtain, later-stage functionalization is more convenient, reaction conditions are mild, and gram-level scale reaction is good; and especially, the compounds with medium yield can be obtained without the catalyst, post-treatment is simple and convenient, the application of the compoumds in drug molecule synthesis and large-scale industrialization is facilitated, and the requirements and trends of modern green chemistry and medicinal chemistry are met.

The invention discloses a preparation method of tert-butyl acrylate, which comprises the following steps: acrylic acid, a catalyst, a polymerization inhibitor and isobutene are added into a reactor, and esterification reaction is carried out at 20-50 DEG C under the pressure of 1-3 MPa at the isobutene volume space velocity of 0.5-5.0/h to synthesize tert-butyl acrylate, wherein the feeding molarratio of the acrylic acid to the polymerization inhibitor to the isobutene is 1: (0.05-0.2): (0.2-0.8), the catalyst is selected from at least one of strongly acidic cation exchange resin, p-toluenesulfonic acid and an acid group modified SBA-15 mesoporous molecular sieve, the polymerization inhibitor is a mixture of tert-butyl catechol and tert-butyl alcohol, and the mass ratio of tert-butyl catechol to tert-butyl alcohol is 1: (1-3). According to the preparation method of tert-butyl acrylate, through the combination of the special catalyst and the polymerization inhibitor, the yield of esterification reaction is greatly improved, the reaction temperature is reduced, and the reaction is milder, greener and more economical.

The invention relates to the technical field of drug synthesis, in particular to a preparation method of a fosphenytoin sodium intermediate, which comprises the following steps: A) under the action of a catalyst, reacting a compound as shown in a formula II with a compound as shown in a formula III in a solvent a; and B) mixing a product obtained after the reaction in the step A) with a solvent b, cooling, and crystallizing to obtain the compound shown in the formula I. In the preparation process of the compound as shown in the formula I, expensive dibenzyl phosphate silver salt does not need to be used, the reaction is more economical, and residues of heavy metals such as silver are avoided; meanwhile, inorganic salts such as potassium chloride and sodium chloride can be effectively removed without a desalting step, so that the operation steps are simplified, and the production efficiency is improved. Moreover, the preparation method provided by the invention can obtain higher yield and purity, is simple and convenient to operate, high in production efficiency, safe and suitable for industrial mass production, and has a good market application prospect.