156results about How to "Enhanced nucleophilicity" patented technology

The invention discloses a 6-aryl amido hexyl hydroximic acid collecting agent and preparation and application methods thereof. 6-aryl amido hexyl hydroximic acid represented by a formula (I) is taken as a collecting agent and utilized in flotation of tungsten ore, tombarthite ore, tin ore or bauxite, wherein R represents H or C1-8 alkyl. 6-aryl amido hexyl hydroximic acid and sodium hydroxide, potassium hydroxide or ammonium hydroxide are put into water to prepare an aqueous solution of 6-aryl amido hexyl hydroxyoximate; a flotation reagent is added for size mixing during an ore grinding and/or flotation process, the added reagent at least contains the aqueous solution of 6-aryl amido hexyl hydroxyoximate, and the dosage of 6-aryl amido hexyl hydroximic acid ranges from 100g/t to 3,500g/t; and useful metallic minerals are floated out through a froth flotation method, and the flotation recovery rate can be increased by 2%-5%.

The invention relates to PNHO tridentate ligands and application of related ligands in asymmetric hydrogenation and similar reactions. The novel tridentate nitrogen-phosphine-oxygen ligands are first tridentate nitrogen-phosphine-oxygen ligands containing ferrocenyl planar chiral phosphine, and are successfully applied to high-efficiency high-selectivity asymmetric hydrogenation and other similar reactions of simple aromatic ketone, alpha-hydroxyketone and beta-ketone ester. Compared with other dominant tridentate ligands, the ligands provided by the invention have the advantages of simple synthesis route and low cost, can easily implement large-scale synthesis, are stable in air, and have high activity and high selectivity in asymmetric hydrogenation reactions of carbon-oxygen double bonds.

The invention discloses a preparation method of alkali metal salt of bis(fluorosulfonyl)amide. The preparation method comprises the step of carrying out fluoridation on alkali metal salt of bis(chlorosulfonyl)amide in an polar aprotic solvent by taking ion liquid as a phase transfer catalyst and alkali metal fluoride as a fluorinating agent, so as to obtain corresponding alkali metal salt of bis(fluorosulfonyl)amide. Compared with the prior art, the preparation method has the advantages that reaction conditions are mild, the yield and the purity are high, the product is easily separated and purified, the ion liquid catalyst can be recycled and reduced, and the like. The preparation method is applicable to industrial mass production.

The invention discloses a preparation method of silicon carbide ceramic precursor polycarbosilane. The method comprises the following steps: (1) adding sodium metal into a reaction solvent, heating upunder stirring and gradually adding halomethyltrialkoxysilane to continue the reaction so as to mainly produce sodium salt, alkoxy-containing polycarbosilane and sodium alkoxide; (2) removing the sodium salt produced in the step (1), adding a reducing agent after heating up, and reducing the alkoxy-containing polycarbosilane to produce a polycarbosilane product. Raw materials used in the preparation are simple in source and high in polymerization activity, and can introduce crosslinking groups through a plurality of different ways; and the obtained polycarbosilane has low viscosity and high purity, and can obtain silicon carbide ceramics with near-stoichiometric ratios after sintering.

The invention relates to a bistriazene compound, in particular to 4, 4'-bis[5, 6-dichloro-2-benzothiazolylazo-amino]biphenyl-3, 3'-disulfonic acid and a preparation method and application thereof. The invention solves the problem existing in the prior art that a reagent for detecting heavy metal ions has nonideal sensitivity. The molecular structural formula of the 4, 4'-bis[5, 6-dichloro-2-benzothiazolylazo-amino]biphenyl-3, 3'-disulfonic acid is shown as follows. The 4, 4'-bis[5, 6-dichloro-2-benzothiazolylazo-amino]biphenyl-3, 3'-disulfonic acid is used for the detection of the heavy metal ions, has the advantages of good selectivity, high sensitivity, and steady performance, can be used for fluorescence detection of Ni (II) in alkaline medium in the presence of a triton surfactant, and can also be used as a visualization reagent for photometric analysis.

The invention provides a preparation method of PEGylated recombinant human granulocyte colony-stimulating factor. The preparation method comprises following steps: (a), an alkali conditioning agent is used for adjusting pH value of a mother liquor containing recombinant human granulocyte colony-stimulating factor to a first pH value; (b), methoxy-polyethylene glycol-propionaldehyde is added into the mother liquor, and an obtained solution is stirred for dissolving; (c), NaBH3CN is added, and an obtained mixture is stirred for reaction; and (d) an acid conditioning agent is used for adjusting pH value of an obtained reaction liquid to a second pH value so as to stop reaction and obtain the PEGylated recombinant human granulocyte colony-stimulating factor. The preparation method is simple; buffer system of a reaction liquid is the same to buffer system of the mother liquor of the recombinant human granulocyte colony-stimulating factor, so that buffer solution replacing is avoided; reaction is stopped by adjusting pH value with hydrochloric acid; product purifying difficulty is reduced; and the preparation method is suitable for industrialized production. The kinds of added reagent are few; and safety of the finished products in clinical application is improved.

The invention relates to the field of flotation, in particular to phenylpropenyl hydroxamate, a preparation method thereof and application thereof to tungsten ore flotation. The preparation method ofphenylpropenyl hydroxamate comprises the following steps: preparing raw materials; preparing hydroxylamine hydrochloride and a sodium hydroxide solution; preparing a crude product of phenylpropenyl hydroxamate; and purifying phenylpropenyl hydroxamate. The optimum pH of phenylpropenyl hydroxamate in ore pulp is close to neutral, so that the flotation is easy to operate, the burden on workers is lowered, chemicals are saved, and the flotation cost is decreased.

The invention relates to a preparation method of a drug for treating diabetes mellitus, that is, repaglinide. The preparation method comprises the following steps: a (S) type compound as shown in formula (II) and a compound as shown in formula (III) are subject to an amidation reaction in the presence of a condensing agent to generate a (S) type compound as shown in formula (IV); R2 radical is removed from the (S) type compound of the formula (IV) in the presence of alkali, and R1 radical is removed in the presence of acid. The (S) type compounds as shown in the formula (II), the formula (III) and the formula (IV), and the R1 radical and the R2 radical are defined in the specification. In the preparation method, the introduction of the R1 radical and deprotection improvement shorten the reaction time, increase the yield and enhance safety, thus the method is more suitable for industrialized production.

The invention relates to a preparation method for high-purity methylphenyl-dimethoxysilane. The preparation method is characterized in that high-purity methylphenyl-dimethoxysilane is prepared through four-step deacidification. The method comprises the following steps: 1) adding dichloromethyl phenylsilane and a hydrogen chloride absorbent into an alcoholysis enclosed agitation reactor, then slowly adding a mixed liquor of absolute methanol and a catalyst drop by drop, controlling a certain reaction temperature, carrying out reflux deacidification at a certain temperature after completion of dropwise addition, carrying out filtering after complete reaction so as to obtain a crude methylphenyl-dimethoxysilane product and recovering the tail gas--hydrogen chloride gas by using a falling film absorption system for preparation of hydrochloric acid; and 2) adding the crude methylphenyl-dimethoxysilane product into a self-made gradient high-efficiency rectifying tower bottom, controlling rectification temperature for fractionation and recovery of methanol and adjusting a reflux ratio to rectify high-quality methylphenyl-dimethoxysilane with quality reaching an international advanced level. The preparation method for methylphenyl-dimethoxysilane has the advantages of environment friendliness, cyclic utilization of resources, stable process, simple operation and product purity of more than 99.5%.

The invention relates to an improved method for preparing a cefprozil dimethyl formamide (DMF) solvate; the method comprises the following steps of: taking a 7-APCA-guanidine salt shown by the formula IV and a mixed anhydride shown by the formula VI as raw materials to carry out a condensation reaction under alkaline conditions, hydrolyzing reaction liquid in the presence of acids, separating the liquid, adding DMF to a water phase, and regulating a pH value with an alkaline to obtain the cefprozil DMF solvate shown by the formula I. The method of the invention avoids the usage of silanizing reagent with expensive cost and instability, improves yield greatly and reduces production cost to form a more economic and efficient preparation technology, wherein X+ and R6 are defined according to claim 1.

The invention relates to an initiation system for preparation of high reaction activity polyisobutylene and application. The initiation system consists of SnCl4, water and an organic compound containing oxygen, nitrogen and/or sulphur. The initiation system is added into an isobutene-containing polymerization raw material to induce cationic polymerization. The polymerization temperature is controlled at -60-30DEG C, and the polymerization reaction is stable and easy to control. Optimally, the terminal group alpha-double bond content can reach 98%. And according to needs, the initiation system can be used to prepare high reaction activity polyisobutylene with a number average molecular weight of 500-5000, a molecular weight distribution index up to 1.3 and an alpha-double bond content greater than 80%mol, a low molecular weight and narrow molecular weight distribution, and high reaction activity polyisobutylene with a number average molecular weight of 8000-15000, a molecular weight distribution index up to 1.6, an alpha-double bond content over 80%mol, a medium molecular weight and narrow molecular weight distribution.

The invention discloses a ratio-type coumarin derivative which can be used for detecting cyanide ions. The structural formula (I) of the coumarin derivative is described in the specification, wherein R is shown in the specification. The coumarin derivative is used for detecting cyanide ions; the process of detecting the cyanide ion is carried out in a buffer solution of Na2CO3-NaHCO3; and the pH value of the buffer solution is 9.4. The coumarin derivative provided by the invention can be used for uniquely, efficiently and simply detecting the cyanide ions, is applicable to detection on cyanide ions in wastewater generated in industrial processes such as electroplating, chemical engineering, metallurgy, mineral separation and surface treatment, and is high in detection sensitivity and good in selectivity.

Provided is a method for producing a 2-cyanoethyl group-containing organic compound having a high ratio of replacement by cyanoethyl groups and a high dielectric constant. More specifically, provided is a method for producing a 2-cyanoethyl group-containing organic compound comprising a step of reacting acrylonitrile with a hydroxyl group-containing organic compound in the presence of a quaternary ammonium salt as a catalyst through a Michael addition.

The invention discloses a preparation method of calcium-containing soluble hemostatic material. The calcium-containing soluble hemostatic material takes polysaccharide fiber as a raw material and is prepared by alkalization, etherification, calcification, alcohol washing and the like. The preparation method is mild in preparation conditions and short in production period which is about 2-3hours. The calcium-containing soluble hemostatic material has rapid hemostatic effect and adopts low-concentration alcoholic solution for washing; and compared with the prior art, the calcium-containing soluble hemostatic material saves 40-50% of alcohol and uses the low-concentration alcohol, thus production technology is simple and suitable for large-scale production.

The invention provides a method for preparing taurine. The method comprises the following steps: carrying out an addition reaction on ethylene oxide and sodium hydrogen sulfite in the presence of a heterogeneous catalyst so as to obtain sodium hydroxyethyl sulfonate at high selectivity; carrying out an ammonolysis reaction on the synthesized sodium hydroxyethyl sulfonate under catalysis of a homogeneous catalyst; and neutralizing, crystallizing, separating and the like, thereby obtaining the finished taurine. Compared with the traditional production process, the process disclosed by the invention has the advantages that by-products in the addition reaction process can be obviously reduced, the temperature and pressure of the ammonolysis reaction are reduced, the reaction time is shortened,and industrial production is easily realized.

The invention relates to a method for preparing 2, 6-difluorobenzonitrile. The method comprises the following steps: adding an aprotic strong polar solvent, toluene, 2,6-dichlorobenzonitrile and a catalyst, controlling temperature to 110-150 DEG C, carrying out reflux and dehydration and removing methylbenzene; cooling to 90-100 DEG C and adding potassium fluoride into a reaction container; controlling reaction temperature to 150-250 DEG C, and reacting for 15-20 h; reducing temperature of the reaction container to below 50 DEG C, carrying out suction filtration to obtain a filtrate and transferring the filtrate into a rectification bottle, starting a vacuum pump with the vacuum degree being -0.1 MPa, and collecting a fraction of 105-108 DEG C so as to obtain a finished product 2, 6-difluorobenzonitrile. In comparison with the prior art, the invention has advantages as follows: reaction conditions are mild; the preparation technology is simple; and reaction yield can reach up to 98%.

The invention provides a tyrosine kinase irreversible inhibitor shown in a formula I or pharmaceutically acceptable salt thereof, a preparation method for the tyrosine kinase irreversible inhibitor and applications of the tyrosine kinase irreversible inhibitor. The invention belongs to the field of pharmaceutical chemistry. The tyrosine kinase irreversible inhibitor or the pharmaceutically acceptable salt thereof is very high in activity of inhibiting growth of cancer cells, and is especially remarkable in effect of inhibiting the growth of cancer cells with high expression of an epidermal growth factor receptor (EGFR) and type-2 human epidermal growth factor receptor (HER2).

A cationically polymerizable composition is provided, which comprises a cationically polymerizable compound, a cationic polymerization initiator, and a specific tertiary alkanolamine or tertiary alkylamine. The cationically polymerizable compound is preferably an alicyclic epoxy compound and an oxetane compound. The above amine accounts for 0.01 to 1.0% by weight, preferably 0.05 to 0.5% by weight of the total of the cationically polymerizable composition and the cationic polymerization initiator accounts for 0.1 to 20 parts by weight based on 100 parts by weight of the cationically polymerizable compound. The composition is excellent in storage stability and dispersion stability of colorants contained therein.

The invention relates to an air atmosphere anion ring-opening polymerization method of an N-sulfonyl aziridine derivative. The preparation method comprises the following step: by taking sulfur anionswith stable air as an initiator, adding the sulfur anions, an N-sulfonyl aziridine derivative monomer and a solvent according to a stoichiometric ratio in an air atmosphere to carry out active anion ring-opening polymerization, so as to obtain a corresponding polymer. The initiator and the monomer of the polymerization system are insensitive to air and water, air atmosphere active anion polymerization can be achieved, the initiator has numerous varieties and is easy to obtain, the polymerization system is suitable for a wide variety of monomers, and large-scale controllable preparation of homopolymers and copolymers of the N-sulfonyl aziridine derivative can be achieved. Because a high vacuum technology and an inert atmosphere are not needed, the method is suitable for industrial scale-upproduction.

The invention discloses a method for producing high-viscosity and high-degree-of-substitution carboxymethyl cassava starch by utilizing an ultrahigh-pressure blasting technique. The method comprises the steps such as alkaline treatment, etherification reaction and purification. The method is carried out by primarily achieving the purpose of destroying a crystallization region of cassava starch particles by utilizing sodium hydroxide, sufficiently swelling and alkalifying starch molecules and loosening starch particles under the ultrahigh pressure of a high-pressure homogenizer, so that the hydroxyl of the starch becomes negative oxygen ions and the nucleophilic ability is strengthened, and simultaneously generating an St-O-Na<+> active center, then, preparing the high-viscosity and high-degree-of-substitution carboxymethyl cassava starch through the bimolecular nucleophilic substitution between sodium carboxymethyl starch obtained by alkalifying the starch and chloroacetic acid under the alkaline condition of sodium hydroxide. By utilizing the high-degree destructive effect of the ultrahigh-pressure blasting technique on a crystallization structure of the cassava starch, the technical problems such as degradation of the starch particles in a production process of the high-viscosity and high-degree-of-substitution carboxymethyl cassava starch are solved.