45 results about "Borane dimethylsulfide" patented technology

The invention relates to a photosensitive Zr-B-Si-C ceramic precursor and an in-situ preparation method thereof. The method is as follows: mix methyl vinyl dichlorosilane and borane dimethyl sulfide evenly, then add metal sodium for dechlorination to obtain methyl vinyl borosilane; mix chloromethyl trichlorosilane, methyl chloride Methyldichlorosilane and dichlorozirconocene are mixed evenly, then metal magnesium is added for the first heat preservation reaction, and then a reducing agent is added for the second heat preservation reaction to obtain polyzirconium carbosilane; methylvinyl borosilane and polyzirconium Carbosilane is mixed uniformly to obtain vinyl Zr-B-Si-C alkane; vinyl Zr-B-Si-C alkane is mixed with mercaptopropionate evenly, and then a photoinitiator is added to initiate a polymerization reaction to obtain the ceramic Precursor. The invention solves the problems of high viscosity, large thermal stress, and attenuation of mechanical properties of structural parts in traditional light-curing systems, and provides high-quality raw materials for light-curing 3D printing ultra-high temperature ceramic structural parts.

The invention relates to a preparation method of chiral S / R-3-ethoxy-4-methoxy-alpha[(methylsulfonyl)methyl] benzyl alcohol. The preparation method comprises the following steps: 3-hydroxy-4-methoxybenzaldehyde is taken as a starting material and reacts with hydroxylammonium hydrochloride to produce 3-hydroxy-4-methoxybenzonitrile; 3-hydroxy-4-methoxybenzonitrile reacts with bromoethane to produce 3-ethoxy-4-methoxybenzonitrile; 3-ethoxy-4-methoxybenzonitrile reacts with dimethyl sulfone under the action of n-butyllithium, a product is hydrolyzed in an aqueous hydrochloric acid solution, and 1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl)ethanone is obtained; finally, S-(-)-alpha,alpha-diphenyl-2-pyrrolidinemethanol or R-(+)-alpha,alpha-diphenyl-2-pyrrolidinemethanol is taken as a chiral catalyst, a borane dimethyl sulfide solution is taken as a reducing agent, carbonyl is reduced, and a product is obtained. The reaction conditions are mild, the product yield is higher, the technology level is increased, the operability is improved, and large-scale industrial production is facilitated.

The present invention relates to a method for synthesizing an anacetrapib intermediate (1R,2S)-1-(3,5-bis(trifluoromethyl)phenyl)-2-Boc-amino-propanol. The method comprises: adding (R)-2-methyl-CBS-oxazaborolidine and a borane-dimethyl sulfide complex to 1-(3,5-bis(trifluoromethyl)phenyl)-2-Boc-amino-acetone in a certain solvent at a certain temperature, and carrying out a reducing reaction. According to the present invention, the chiral catalytic reaction does not use the expensive metallic ruthenium catalyst, the catalytic selectivity is high, the reaction condition is mild, the product is single, the obtained intermediate has the high optical purity and the high yield, the production cost is low, and the method is environment is environmentally friendly, and is suitable for Industrial production.

The invention discloses a synthesis method of Mirabegron, which comprises the following processing steps: S1. Under room temperature conditions, R-2 (aminomethyl) benzyl alcohol, 2-(2-aminothiazole-5-yl)- N-[4-(2-chloro-ethyl)-phenyl]-acetamide and triethylamine were added to the solvent and refluxed for 8h; S2, after the reaction was completed, the reaction solution was pumped into water, filtered to obtain Mirabegron . The solvent in the step S1 is one or more of methanol, ethanol, propanol, dichloromethane, chloroform, acetone, butanone, and toluene. The present invention not only does not use irritating organic solvents, but also does not use dangerous borane dimethyl sulfide and high temperature and high pressure, not only the reaction process is green and environmentally friendly, clean production is realized, but also the cost is reduced, which has better market competition force.

The invention discloses a new method for preparing tetrahydrofuran-3-potassium trifluoroborate. The new method specifically comprises the following steps: preparing di-alpha-pinoborane by using dextro-alpha-pinene and a borane-dimethyl sulfide complex as raw materials, then reacting di-alpha-pinoborane with 2,5-dihydrofuran at room temperature, then using anhydrous acetaldehyde for reduction to generate dimethyl borate, without separating an intermediate, and subsequently reacting dimethyl borate with a saturated aqueous solution of KHF2 to generate the target product tetrahydrofuran-3-potassium trifluoroborate. The method has the obvious advantages that the reaction raw materials are easy to obtain; the reaction operation is simple; large-scale production is easy to achieve; the yield is high; the purity is good; the production cost is low.

The invention provides a method for reducing diyne compounds. The method for reducing the compounds represented by a formula I comprises the following steps: (1) a system of a borane reagent and tetrahydrofuran is provided, wherein the borane reagent is a borane dimethylsulfide solvent; (2) cyclohexene is dropped into the system of borane reagent and tetrahydrofuran, such that a borane system comprising active hydrogen is obtained; (3) the compound represented by the formula I is added into the borane system comprising active hydrogen, and a reduction reaction is carried out, such that a compound represented by a formula II can be obtained. With the method, diyne compounds can be effectively reduced into diene compounds. In the entire process of the method, reaction materials are easy to obtain; reaction post-treatment is simple; industrial three-waste treatment is easy; and target product yield is high. The method is suitable for industrialized productions.