35results about How to "The reaction process is safe and controllable" patented technology

The invention relates to a preparation method of Pramiracetam sulfate. The preparation method comprises the steps of using N, N-diisopropylethanolamine as a starting raw material, and conducting chlorination and ammonolysis to obtain an intermediate N, N- diisopropylethylene diamine; then conducting acylation, substitution, salt forming and refining to obtain the Pramiracetam sulfate. The preparation method of the Pramiracetam sulfate has the characteristics that the reaction process is safe and controllable, the cost of used raw materials and solvent is low and the raw materials and the solvent are easy to obtain; organic solvent is very easy to recycle, the emission of organic matters is greatly reduced, and the environmental friendliness is improved; since the intermediate N-[(2-diisopropyl amino) ethyl]-chloroacetamide is not separated and purified, the reaction equipment is simplified, and the operation process is enabled to be more high-efficient.

The invention discloses a method for preparation of a ketone compound and its derivatives by means of a carboxylic acid compound and a carboxylic ester compound in the presence of alkali. The method has the characteristics of wide substrate adaptability, short reaction time, high yield and high atom economy. The use of Lewis acid and heavy metals is avoided, the experimental operation steps are simple, the corrosion to equipment is small, and the amount of ''three wastes'' is small, so that the method is conducive to further promotion and application and industrial production.

Acetylenic ketone compounds and a preparing method thereof are disclosed. The general formula of the acetylenic ketone compounds is shown as a formula (I) in the specification. The preparing method includes adding an aldehyde compound A and a high-valence iodoalkyne compound B into a reaction system comprising a copper/gold salt catalyst, a secondary amine catalyst, a ligand catalyst and an oxidant and reacting at a temperature ranging from -20 DEG C to 200 DEG C. The acetylenic ketone compounds have a typical acetylenic ketone structure, have similarity with other acetylenic ketone compounds, and can be used for development of medicine intermediates and preparation of functional materials. The preparing method is simple in process, low in reaction condition requirements, safe and controllable in reaction procedures, high in atom utilization rate, high in production efficiency, and low in environment pollution stress, and obviously reduces the production cost of the acetylenic ketone compounds provided by the invention.

The invention belongs to the technical field of capacitor dielectric materials, and particularly relates to nanocrystalline barium titanate ceramic and a preparation method thereof. The preparation method of the nanocrystalline barium titanate ceramic comprises the following steps of: mixing barium carbonate and titanium dioxide, and carrying out ball milling, sanding, drying, sieving and calcining to obtain the barium titanate ceramic. The preparation method of the nanocrystalline barium titanate ceramic comprises the following steps of: mixing and ball-milling barium carbonate and titanium dioxide to increase the sintering activity of barium carbonate and titanium dioxide; carrying out solid-phase synthesis by using a sanding method to obtain barium titanate nano-powder with relatively small particle size and high tetragonality; the barium titanate nano-powder is subjected to calcination treatment, and the obtained nanocrystalline barium titanate ceramic has a small grain size and ahigh dielectric constant and can meet the requirement that a capacitor contains 5-6 ceramic grains in each single dielectric medium when being used as a ceramic capacitor material.

The invention discloses diarylmethane compounds as well as a preparation method and application thereof. The diarylmethane compounds have a molecular structural general formula as defined by a generalformula (I) in the description. The preparation method of the diarylmethane compounds comprises the steps of adding a benzyl halogenated hydrocarbon compound A and an arylboronic acid B into a reaction system containing an organic small-molecular catalyst, an alkali reagent and a solvent, and performing a reaction to prepare the compounds. The diarylmethane compounds provided by the invention contain electron withdrawing groups and an electron-donating group substituted diarylmethane basic structure, and can be widely used for synthesis of pharmaceutical intermediates, particularly polysubstituted methane compounds, and preparation of functional materials; and the preparation method has a simple process and low requirements for reaction conditions, the reaction process is safe and controllable, the atomic utilization rate and production efficiency are high, the regioselectivity and stereoselectivity of the products are efficiently ensured, a frontier science small-molecule organocatalysis concept is introduced, and the method is friendly to the environment.

The invention discloses 1,2,3,4-tetrahydronaphthalene compound and a preparation method and application thereof. The 1,2,3,4-tetrahydronaphthalene compound has a molecular structural formula shown asformula (I) that is shown in the description. The preparation method of the 1,2,3,4-tetrahydronaphthalene compound comprises steps, such as subjecting styrene compound A, olefine compound B, a visiblelight catalyst, a cocatalyst and a solvent to reacting. The 1,2,3,4-tetrahydronaphthalene compound has a tetrahydronaphthalene basic framework containing electron-withdrawing group and electron-donating group substations, and is widely applicable to the preparation of functional materials and the synthesis of pharmaceutical intermediates, especially polycyclic-structure compounds. The preparationmethod herein is simple and has low reaction condition requirements, the reaction process has good safety and controllability, atom utilization rate and production efficiency are high, regio-and stereo-selectivity of products is effectively ensured, and the products have no pollution.

The invention provides a preparation method and application of anhydrous peroxycarboxylic acid. The preparation method comprises the following steps: carrying out reduced pressure dehydration and pre-concentration on low-concentration hydrogen peroxide, adding a catalyst a and a catalyst b, adding carboxylic acid, and carrying out electrolytic oxidation reaction to synthesize the anhydrous peroxycarboxylic acid. According to the method, the oxidation reaction effect is enhanced through the synergistic effect of electrons and metal salt, no pollution is caused, the requirement of green synthetic chemistry is met, and the prepared peroxycarboxylic acid does not contain water and can be used for preparing epsilon-caprolactone.

The invention relates to a preparation process of glucosamine sulfate. The preparation process comprises the following steps of (1) uniformly stirring glucosamine hydrochloride and monohydric alcohol to obtain an alcoholic solution of glucosamine hydrochloride for later use; (2) adding an alkaline neutralizer into the alcoholic solution, adding a silver sulfate solution after the reaction is finished, stirring, standing, and carrying out solid-liquid separation on the reaction system; and (3) adjusting the liquid separated in the step (2) to be acidic, then distilling to obtain glucosamine sulfate, and recovering the distilled solvent. Silver sulfate is adopted to fix chloride ions in glucosamine hydrochloride in a monohydric alcohol system in a silver precipitation mode; compared with traditional adsorption, extraction and other methods, the method is efficient and rapid, more importantly, the chloride ions in glucosamine hydrochloride can be thoroughly removed; and the obtained silver precipitate is easy to separate and recover and can be used as an industrial by-product, and no extra solid waste is generated.

The invention discloses a preparation method of an iron-aluminum-chromium filter material, and relates to the field of material processing and manufacturing. The problems that an existing filtering material is complex in preparation process and high in cost, and potential safety hazards exist in the preparation process are solved. The preparation method comprises the steps that iron powder with the particle size ranging from 75 micrometers to 750 micrometers, aluminum powder with the particle size ranging from 5 micrometers to 40 micrometers and chromium powder with the particle size ranging from 50 micrometers to 180 micrometers are stirred in a ball mill for 120 minutes, an initial ingredient is obtained, in the initial ingredient, the atom percentage content of the iron powder ranges from 65% to 70%, the atom percentage content of the aluminum powder ranges from 23% to 25%, and the atom percentage content of the chromium powder ranges from 2% to 5%; the initial ingredient is placed in a cold isostatic press to be pressed into a pressed blank, and the pressing pressure ranges from 200 Mpa to 260 Mpa; the pressed blank is placed in a sintering furnace filled with hydrogen to be subjected to in-situ reaction sintering, heat preservation is conducted for 2-3 h, the filtering material is obtained, and the temperature in the sintering furnace ranges from 1200 DEG C to 1300 DEG C during in-situ reaction sintering.

The invention provides a preparation method of 2-(2-(2-aminoethoxy) ethoxy) acetic acid, and belongs to the field of pharmacy. The method comprises the following steps of: (1) taking a compound A0 and Bn2NH as raw materials to react to prepare a compound A1; (2) taking the compound A1 and an oxidizing agent as raw materials to react to prepare a compound A2; (3) taking the compound A2 and hydrogen as raw materials to react to prepare a compound A3; and (4) taking the compound A3 and fluorenylmethoxycarbonyl succinimide as raw materials to react to prepare the 2-(2-(2-amino ethyoxyl) ethyoxyl) acetic acid. Compared with a preparation method in the prior art, the preparation method disclosed by the invention avoids the use of a dangerous raw material NaH, and is mild in reaction condition, safe and controllable in reaction process, high in product yield and purity and suitable for industrial production.