39 results about "Trimethylbromosilane" patented technology

The invention relates to a synthesis method for making cefpirome sulfate. The method comprises the following steps that: cefotaxime and 2, 3-cyclopenopyridine, with the molar ratio of between 1:7 and 1:12, are mixed with trimethyl bromosilicane used as protecting agent inside organic solvent to carry out substitution reaction, thereby generating cefpirome dihydrobromide; and the salt-forming reaction of the cefpirome dihydrobromide is carried out to make cefpirome sulfate. According to the synthesis method of cefpirome sulfate provided by the technical proposal of the invention, cefotaxime and trimethyl bromosilicane are respectively used as raw material and protecting agent to make cefpirome sulfate. Because enough supply and technical maturity of cefotaxime are realized in China and trimethyl bromosilicane is more active than trimethylchlorosilane and is cheaper than trimethyliodosiliane, the synthesis method has the advantages of low cost of raw material, high yield, simple synthetic route and convenient operation.

The invention provides a method for synthesizing L-carnitine by using (R)-(-)-3-chlorine-1,2-propylene glycol as a chiral initiative raw material, which belongs to the field of medicament chemistry. The method comprises the following steps of: mixing a side product, namely (R)-(-)-3-chlorine-1,2-propylene glycol used as the initiative raw material with triethyl orthoacetate for reacting to produce an annular condensation compound, wherein the side product is generated when the L-carnitine is prepared by chirally splitting racemic epoxy chloropropane; reacting the annular condensation compound with trimethylsilyl bromide to obtain brominated substance; reacting the brominated substance with sodium cyanide to produce cyanide; reacting the cyanide with trimethylamine to produce ammonium chloride salt; and performing hydrolysis and ion exchange on the ammonium salt under the acidic condition to produce the L-carnitine finally. The method has the advantage that: the L-carnitine is prepared by using the side product, namely (R)-(-)-3-chlorine-1,2-propylene glycol which is generated when the L-carnitine is prepared by chirally splitting racemic epoxy chloropropane as the chiral initiative raw material and by adopting low-cost and readily available chemical raw materials, the reaction condition is simple and mild and the conversion efficiency is high.

The invention discloses a method for synthesizing bromotrimethylsilane, and relates to a synthetic production technology for a chemical product. The method comprises the following steps of: under oxygen-free conditions, stirring in a reaction kettle in which phosphorus tribromide and silyl ether are sequentially added, raising the temperature to 1005 DEG C, keeping the temperature, performing reflux reaction for 60.5 hours, rectifying under normal pressure to obtain the bromotrimethylsilane, and stopping to receive a finished product of the bromotrimethylsilane when the temperature in the kettle is raised to 135 DEG C. By the method, a silyl ether-phosphorus tribromide method is improved and innovated, side reactions are avoided, the obtained product has purity, and the finished product of the bromotrimethylsilane which has the content of about 99 percent can be obtained; and the stirring at normal temperature is changed into high-temperature reflux, so that the reaction time is greatly shortened.

The invention discloses a method for highly regioselective bromination of phenolic compounds. In the method, trimethylbromosilane is used as a brominating agent, aryl sulfoxide is used as an activator, and phenolic compounds are mixed at 0-50°C. Stirring and reacting in a solvent and nitrogen atmosphere for 1 to 12 hours to achieve high regioselective bromination of phenolic compounds, and obtaining brominated phenolic compounds through filtration, extraction or separation and purification by column chromatography. The present invention adopts aryl sulfoxide as the activator, and the sulfoxide substituent is large, so that on the one hand, the regioselectivity of the bromination reaction of the phenolic compound is relatively high, and when the phenolic compound has no substituent at the para-position of the hydroxyl group, the regioselectivity is obtained. The product of para-bromo, and when the phenolic compound hydroxyl has a substituent at the para-position, the regioselectivity obtains the product of ortho-bromo; on the other hand, if it is separated and purified by filtration and extraction, the separation and purification of by-products can be realized simultaneously. Recycling, compared with column chromatography, reduces the cost of separation and purification.

The invention relates to a novel method for preparing tenofovir, in particular to a method for preparing a tenofovir compound, in particular the monohydrate of the tenofovir for resisting hepatitis B viruses and human immunodeficiency viruses. The method comprises the following steps of: using (substituted) triphenylchloromethane XIII to protect hydroxy in the end position of (R)-1,2-propanediol, condensing the obtained product with dialkyl sulfonyloxy methyl phosphonate V to obtain XV, hydrolyzing the XV in the aqueous solution of an organic acid to remove the protective group of the hydroxyl at the end position of XV to obtain an intermediate XI, condensing sulfonate XII of the intermediate XI with adenine to obtain an intermediate VII, transforming the intermediate VII into the corresponding trimethylsilyl phosphonate VIII by trimethylsilyl bromide (TMSBr), and hydrolyzing the VIII to obtain the target product. The method has the advantages of short process route, convenient operation, low cost and easy access of raw materials and favorability for large scale production.

The invention provides a preparation method of a pyrrole compound and belongs to the technical field of pharmacy. The preparation method comprises that a raw material compound and a halogenation reagent undergo a reaction in an organic solvent to produce a target compound. The halogenation reagent is trimethylchlorosilane, trimethylbromosilane, triethylchlorosilane, tert-butyl dimethylchlorosilane, phenyl dimethylchlorosilane, oxalyl chloride, acetyl chloride, phosphorus oxychloride, phosphorus pentachloride, phosphorus pentabromide, thionyl chloride, sulfuryl chloride or their composition. The preparation method can prevent harsh conditions such as use of hydrogen chloride gas, is carried out under simple reaction conditions, is easy to operate and control and is suitable for industrial production.

The present invention provides a method for preparing a 16-ene steroid compound. The compound of formula I is used as a substrate, and trimethylhalosilane is used as a dehydrating agent. The methyl halosilane is selected from one or more of trimethylchlorosilane, trimethylbromosilane and trimethyliodosilane. The beneficial effect of the present invention is to provide a method for preparing a 16-ene steroid compound with mild reaction conditions, friendly environment, easy operation, low cost and high molar yield, using trimethylhalosilane as a dehydrating agent, which is cheap and easy to obtain, The new process of the invention has more industrial value, can effectively control side reactions, and improve the reaction yield and quality.

The invention belongs to the technical field of a fuel battery and particularly relates to a phosphoric acid grafted polyimide high-temperature proton exchange membrane and a preparation method thereof. The proton exchange membrane is prepared by a method comprising the following steps: firstly performing a bromination reaction on a benzene ring of a common diamine monomer to obtain bromized diamine; replacing bromine on the bromized diamine with phosphonate by using n-butyllithium and chlorophosphate so as to obtain phosphate grafted diamine; performing polycondensation reaction by using the phosphate grafted diamine, the common diamine and dianhydride to prepare the polyimide; and finally hydrolyzing the phosphonate on the polyimide by using trimethyl bromo-silicane and hydrochloric acid to prepare the phosphoric acid grafted polyimide high-temperature proton exchange membrane. The proton exchange membrane prepared by the method disclosed by the invention is excellent in proton conduction capability at a high temperature; the phosphoric acid is chemically boned in a polymer, hard to leak and good in hydrolysis resistance and stability; the phosphoric acid can also cooperate with N in the polyimide to form a continuous hydrogen bond network so as to realize water-free proton conduction.

The invention provides a tenofovir preparation method suitable for industrialized production. According to the method, tenofovir is obtained through catalyzing and hydrolyzing a raw material intermediate (R)-9-[2-(diethylphosphonomethoxy)propyl]adenine via trimethylbromosilane, wherein the raw material intermediate (R)-9-[2-(diethylphosphonomethoxy)propyl]adenine is obtained through the following steps: firstly, obtaining (R)-9-(2-hydroxypropyl)adenine via the ring-opening condensation of adenine and (R)-epoxypropane under an alkaline condition; secondly, catalyzing the (R)-9-(2-hydroxypropyl)adenine through lithium t-butoxide; thirdly, conducting etherification on the catalyzed (R)-9-(2-hydroxypropyl)adenine and p-benzenesulfonyloxymethyl phosphoric acid diethylester, so as to obtain the (R)-9-[2-(diethylphosphonomethoxy)propyl]adenine. The method is characterized in that purified water of appropriate proportion is added in a mixed product obtained through catalyzing and hydrolyzing the (R)-9-[2-(diethylphosphonomethoxy)propyl] adenine via trimethylbromosilane; the tenofovir is obtained through spontaneous crystallization at an appropriate temperature and cooling rate, as well as at an appropriate stirring speed. According to the invention, the obtained tenofovir product has the characteristics of high yield, strong indissolubility in operation under room temperature, simplicity in filtration and collection due to large particles, short production time, low energy consumption, and the like.