45results about How to "Synthetic process conditions are mild" patented technology

The invention relates to a compounding method to form water solubility intermolecular association ternary hydrophobic association polymer that includes acrylamide, sodium acrylate, and allyl-alkylphenyl aether three constructions. The method includes the following steps: using acetone as reacting solvent, alkylphenols and allyl chloride as raw material, benzyl triethyl ammonium chloride as phase-transfer catalyst, reacting for 4-8 hours at 40-60 degree centigrade to form drainage monomer allyl-alkylphenyl aether; adding sodium acrylate, acrylamide and allyl-alkylphenyl aether monomer into reactor according to the mol ratio as 20-30:69.2-79.2:0.8, adding inducing agent, sealing reacting for 2-6 hours to gain terpolymer. The terpolymer has good temperature resistance, saline tolerance, dissolubility and high temperature stability. The invention is easy to compound and has mild condition.

The invention discloses a method for preparing high purity (99.9 percent) 4,4'-difluorobenzophenone, wherein 4-fluorotoluene and liquid chlorine are taken as starting raw materials and then are processed through chlorination reaction, hydration reaction and condensation reaction, and high purity (99.9 percent) 4,4'-difluorobenzophenone is obtained finally. The method gives up the conventional synthetic route; 4-fluorotoluene is processed through chlorination, hydration and condensation firstly to obtain 4,4'-difluorobenzophenone, wherein the melting point of 4,4'-difluorobenzophenone ranges from 107 to 108 DEG C, and the purity of 4,4'-difluorobenzophenone is 99.9 percent; the purity of 4,4'-difluorobenzophenone exceeds the conventional technical standard (99.7 percent) of English ICI (Imperial Chemical Industries Ltd.); in the preparation technology of the method, the adopted raw materials are easy to get, the synthesis process conditions are mild, and almost no environment hazards can be caused. The method satisfies the technical requirements of special engineering plastic containing polyether-ether-ketone on monomers.

The invention discloses a preparation method of a polyaniline@polypyrrole conductive composite material, which comprises the following steps of: firstly synthesizing PAn by a chemical oxidation method, and performing leaching, cleaning and drying to obtain deep green powder of PAn; then mixing a certain amount of polyaniline with a certain amount of water by an in-situ polymerization method, adding doping agent sulfamic acid and pyrrole monomer respectively, uniformly stirring the mixed liquid, and adding an oxidant ferric trichloride; then filtering the reaction liquid, and washing until the filtrate is neutral; and finally drying the filter cake and grinding to obtain black polyaniline@polypyrrole conductive powder.

The invention discloses an imine salt derivative, a preparation method thereof and a preparation method of nicotine. The preparation method of nicotine includes the steps of: adding an imine salt derivative shown as general formula (I) or (II) in the specification and a reducing agent into a solvent for reaction to prepare a racemic nicotine solution; adding a second quenching agent into the racemic nicotine solution to obtain a nicotine precursor solution; and adding an extracting agent into the nicotine precursor solution, conducting reduced pressure concentration, and performing drying andremoving the solvent, thus obtaining nicotine. According to the invention, through the imine salt derivative intermediate synthesized for the first time and the use of the cheap reducing agent, the intermediate is reduced under a relatively mild condition to obtain racemic nicotine. Compared with the existing nicotine synthesis process, the method has the advantages of mild synthesis process conditions, simple equipment requirement, high product purity and high synthesis rate, and is particularly suitable for industrial production.

The invention discloses a method for preparing high-purity 4,4'-difluorobenzophenone. p-fluorotoluene is used as an initial raw material and oxidation reaction, chloroformylation reaction and condensation reaction are carried out, so that the target product 4,4'-difluorobenzophenone is finally obtained; the melting point of the product is 107-109 DEG C; the purity of the product is greater than or equal to 99.9 percent and accords with the purity requirement for synthesis of polyether-ether-ketone (PEEK). Moreover, according to the preparation method disclosed by the invention, the used raw material is cheap and is easy to obtain, the synthetic process conditions are mild and in the synthesizing process, a used reagent is relatively green and environmental-friendly, and thus, the method has wide application prospect and high industrial value.

The invention discloses a novel method for synthesizing a dietary supplement melatonin, and belongs to the technical field of pharmaceutical chemical synthesis. According to the method, N-acetyl serotonin is used as a starting raw material, melatonin is obtained through one-step methylation reaction, the synthesis process is simple, the synthesis process conditions are mild, the yield is as high as 98.5% or above, the quality is good, the content is larger than 99.5%, and the melatonin completely meets the USP42 standard. The new method for synthesizing the dietary supplement melatonin provided by the invention saves the cost and is easy for industrial production.

The invention relates to a method for preparing pH-responsive comb-structure polycarboxylic acid through terminal group functionalization. According to the method, with a pH-responsive monomer, unsaturated halogenated hydrocarbon, a small carboxylic acid momonomer and the like as raw materials, a polycarboxylate material is prepared through self-polymerization first, then substitution and then copolymerization; namely, with the pH-responsive monomer as a reactant, a terminal group-functionalized pH-responsive polymer chain is produced through the self-polymerization under the actions of an initiator and a terminal group functionalizing agent, then a substitution reaction is performed on the terminal group-functionalized pH-responsive polymer chain and the unsaturated halogenated hydrocarbon to obtain a pH-responsive macromonomer, and finally a copolymerization reaction is performed on the pH-responsive macromonomer and the small carboxylic acid momonomer under the action of the initiator to obtain a comb-structure polymer which uses polycarboxylic acid as a main chain and has a side chain with a pH-responsive function. By the method, the process is high-efficiency and energy-saving, the conversion rate of a product is high, the functional modification of the polycarboxylic acid is successfully achieved through introduction of the pH-responsive polymer side chain by a terminal group functionalization method, an excellent characteristic of inhibiting shrinkage of cement mortar is shown, and the market competitiveness and the application prospect are very good.

The invention discloses a method for preparing a concrete water reducer with styrene sulfonate as monomers, and belongs to the field of water reducers. The method includes the steps that firstly, styrene sulfonate and unsaturated carboxylic acid monomers are subjected to free radical copolymerization to obtain a polycarboxylic acid-styrene sulfonate main chain, and then benzene sulfonate on the main chain is modified into phenylsulfonyl halide groups; then, an oxidation-reduction initiating system is formed by high-valence cerate and alcohol to initiate polymerization of unsaturated cationic quaternary ammonium monomers to obtain a hydroxyl-terminated cationic long chain; then, the polycarboxylic acid main chain containing the phenylsulfonyl halide groups, the hydroxyl-terminated cationic long chain and a polyethylene glycol compound are subjected to sulfonylation to obtain the concrete water reducer. According to the method, based on the molecular structure design principle, by modifying styrene sulfonate into phenylsulfonyl halide and carrying out sulfonylation on grafted cationic side chains and polyethylene glycol side chains, the novel concrete water reducer containing a double-side-chain structure is successfully synthesized; the reaction process is mild, easy to control, capable of saving energy and efficient, and the concrete water reducer shows multiple excellent effects of water reduction for slump loss resistance, clay resistance and the like.

The invention belongs to the technical field of catalytic organic synthesis, and specifically relates to a calix[4]squaramide cyclohexanediamine derivative and a method for catalyzing an asymmetric Michael addition and acetalization tandem reaction by using the derivative. With an unsaturated keto ester and 1,3-dicarbonyl cycloketone as raw materials, the calix[4]squaramide cyclohexanediamine derivative as a catalyst, and dichloromethane as solvent, the Michael addition and acetalization tandem catalytic reaction is performed; after the reaction is finished, the solvent is concentrated and a product is obtained through separation by silica gel column chromatography. A calix[4]squaramide cyclohexanediamine catalyst involved in the invention is mild in synthesis process conditions, the separation of an intermediate is not needed, the catalytic efficiency is high, a relatively good ee value can be obtained by the catalytic reaction under the condition of room temperature, and broad application prospects are realized.

The invention relates to the technical field of medicine, in particular to a synthesizing method of a sitagliptin key intermediate. The sitagliptin key intermediate (R)-4-chloro-3-amino-4-(2,4,5-trifluoro-phenyl)butyrate after the raw material trifluoro-benzene is subjected to friedel-crafts acylation, hydrolysis, helium atom replacement, condensation, ammonolysis, hydrogenation reduction and hydrolysis. The method has the advantages that low-price trifluoro-benzene serves as the initial raw material and is wide in source; the chiral center is established through a hydrogenation reduction in which metal rhodium and chiral ferrocenyl diphosphine participate, helium atoms are introduced to the left side of a reaction locus, and therefore the optical purity of the product is effectively improved; the synthesis process conditions are mild and easy to control.