30 results about "Lithium methoxide" patented technology

The invention provides a method for preparing cefoxitin sodium, which comprises the following steps: 1, using deacetyl7-ACA as a raw material, and introducing thiopheneacetyls to obtain an deacetylthiophene acid I; 2, introducing carbamoymethoxyls to the positions 3 of molecules of deacetylthiophene acid I to obtain an intermediate of (6R, 7S)-3-carbamoymethoxyl-7-[2-(2-theiophene) acetamino]-8-oxo-5-thia-1-azabicyclo[4.2.0]octa-2-en-2-methanoic acid II; 3, reacting the intermediate II with lithium methoxide to introduce methoxyls into positions 7 of the molecules of the intermediate to obtain cefoxitin acid III; and 4, adding ethanol solution of a sodium salt into an organic solvent containing the cefoxitin acid and obtaining the cefoxitin sodium IV through suction filtration and drying.

The invention discloses a solid basic catalyst, a preparation method of the solid basic catalyst and an application of the solid basic catalyst in ester exchange reaction. The solid basic catalyst catalyzes the ester exchange reaction by the reaction of metal organic compound and hydroxyl on a carrier under the moderate conditions to synthesize dimethyl carbonate. The solid basic catalyst provided by the invention consists of metal organic alkali and the carrier. The metal organic alkali is linked to the carrier in bond-forming manner; the metal organic alkali is one or more of lithium methoxide, lithium ethoxide, lithium isopropoxide, lithium n-butoxide, lithium tert-butoxide, sodium methoxide, sodium ethoxide, sodium isopropoxide, sodium n-butoxide, sodium tert-butoxide, potassium methoxide, potassium ethoxide, potassium isopropoxide, potassium n-butoxide and potassium tert-butoxide; the carrier is one or more of silicon oxide, aluminium oxide, titanium oxide, zirconia, mesoporous silicon oxide synthesized by the template method, mesoporous aluminium oxide synthesized by the template method, mesoporous titanium oxide synthesized by the template method, and mesoporous zirconia synthesized by the template method.

The invention belongs to the technical field of ternary material precursor preparation, and particularly to a method for preparing lithium aluminate modified ternary anode materials based on spent lithium-ion battery cathode materials. The method comprises the steps that anode materials are separated from spent lithium-ion batteries; the anode materials are leached in a caustic solution and filtered; lithium carbonate is obtained by adding carbonate to filtrate; a filter cake is leached with sulfuric acid and leaching liquid is obtained; an adjustment solution is obtained by adjusting the molar ratios of nickel, cobalt and manganese in a leaching solution; the adjustment solution, an ammonia water solution and a caustic solution are flow into a reaction still together, and the ternary material precursor is prepared by coprecipitation; then the ternary material precursor is mixed with lithium carbonate for roasting, and ternary anode materials are obtained; and the lithium aluminate modified ternary anode materials are prepared by adding sec-butyl alcohol, lithium methoxide and the ternary anode materials in a mixture of ethyl acetoacetate, ethanol and water for reaction and roasting. The ternary anode materials have good structure stability, good electrochemical performance, lower production cost and high product quality, and realize the directional circulation of nickel-cobalt-manganese lithium resources.

The invention relates to a technique for producing lithium alkoxide, which is characterized by comprising the following steps: adding lithium metal into a reactor, dripping ethanol slowly at a temperature of between 20 and 30 DEG C, providing ice water outside the reactor to reduce reaction temperature to between 60 and 80 DEG C in a reaction process, and after finishing dripping the ethanol, keeping the temperature to make full reaction to obtain liquid lithium alkoxide; and then conveying the liquid lithium alkoxide to a closed drier, condensing and drying the liquid lithium alkoxide to obtain solid lithium alkoxide. Reaction of the liquid lithium alkoxide is finished in the reactor firstly, and then materials are conveyed to the drier to be condensed and dried so as to obtain the solid lithium alkoxide. The technique is suitable for industrialized production of lithium methoxide, lithium ethoxide, lithium n-butylate, lithium tert-butylate, lithium isopropoxide or other lithium alkoxides; and the obtained product has high purity.

The invention discloses an epoxy polyphenyl ether proton membrane. The proton membrane comprises the following raw materials in parts by weight: 7 to 9 parts of glycidol, 10 to 14 parts of methyl methacrylate, 70 to 80 parts of polyphenyl ether, 10 to 12 parts of 27 to 30% caprolactam water solution, 3 to 4 parts of doped carbon nanotube, 1 to 3 parts of triethylamine, 0.01 to 0.02 part of lithiummethoxide. The proton membrane takes the glycidol and methyl methacrylate as raw materials, obtains the carbon nanotube modified polyphenyl ether subjected to epoxidation treatment under the catalytic action of lithium methoxide, then the carbon nanotube modified polyphenyl ether is mixed with caprolactam, epoxy is subjected to ring opening under the catalytic action of triethylamine, the formation of the membrane is effectively promoted, meanwhile the dissolving property of polyphenyl ether in dimethyl formamide is improved, the dissolving rate is increased, the material utilization is improved, and the thickness and comprehensive quality of the proton membrane are improved.

The invention discloses an exhaust waste heat returning system of a lithium methoxide battery series-parallel type hybrid electric vehicle. The exhaust waste heat returning system is arranged on the lithium methoxide battery series-parallel type hybrid electric vehicle so as to recycle the tail gas waste heat of a methanol engine. The methanol engine connected with a gas path of a methanol reformed gas device (8) and a lithium battery (2) provide power for the hybrid electric vehicle, and the methanol reformed gas device (8) is provided with an electric heater (9). The exhaust waste heat returning system is characterized in that the power exhaust waste heat returning system is composed of a controller, a valve system, corresponding pipelines and a temperature sensor, wherein the valve system and the corresponding pipelines are controlled by the controller, and the temperature sensor provides temperature information for the controller (1); a tail gas opening of the engine (5) is connected with a gas inlet end gas path of a first reversing valve (4); and the gas outlet end of the first reversing valve (4) is provided with three branches, namely, a first branch emptied through a silencer (11), a second branch for heating an outer cavity of the lithium battery (2) and a third branch for providing auxiliary heat for the methanol reformed gas device (8). According to the tail gas heat recycling system, exhaust waste heat can be fully utilized so that the aims of saving non-renewable energy resources and protecting the environment can be achieved, and the system is suitable for various loaded hybrid electric vehicles.

The invention discloses a technology for preparing lithium aluminate powder. Aluminum isopropoxide and lithium methoxide are converted into lithium aluminate nanotube bundles under the low-temperature hydrothermal condition. The technology includes the steps of mixing the aluminum isopropoxide, the lithium methoxide and deionized water; adding surfactants; carrying out refluxing till gelatinization is achieved; carrying out distilled water stirring hydrolysis; carrying out ultrasonic dispersing; carrying out a hydrothermal reaction; carrying out washing through distilled water; carrying out roasting. The ratio of alcohol to alkoxide generated after the aluminum isopropoxide, the lithium methoxide and the deionized water are mixed is 50:1 to 55:1, and the stirring temperature is 60 DEG C. The temperature of the hydrothermal reaction is 150 DEG C to 160 DEG C, and the reaction time is 2 d to 3 d. The roasting temperature is 500 DEG C to 600 DEG C, and the roasting time is 30 h to 40 h. The technology is easy to operate; the prepared lithium aluminate powder is stable in quality, good in insulation performance and high in mechanical strength, the good chemical stability is achieved at the high temperature, and the good application prospects are achieved.

The invention provides a method for preparing cefoxitin sodium, which comprises the following steps: 1, using deacetyl7-ACA as a raw material, and introducing thiopheneacetyls to obtain an deacetylthiophene acid I; 2, introducing carbamoymethoxyls to the positions 3 of molecules of deacetylthiophene acid I to obtain an intermediate of (6R, 7S)-3-carbamoymethoxyl-7-[2-(2-theiophene) acetamino]-8-oxo-5-thia-1-azabicyclo[4.2.0]octa-2-en-2-methanoic acid II; 3, reacting the intermediate II with lithium methoxide to introduce methoxyls into positions 7 of the molecules of the intermediate to obtain cefoxitin acid III; and 4, adding ethanol solution of a sodium salt into an organic solvent containing the cefoxitin acid and obtaining the cefoxitin sodium IV through suction filtration and drying.

The invention discloses a mixed woven flame-retardant filter bag glass fiber which comprises, by weight, 2-4 parts of diethyl aluminum phosphinate, 50-60 parts of terephthalic acid, 70-80 parts of glycol, 1-2 parts of catalysts, 100-130 parts of amino glass fiber solution, 6-7 parts of methyl methacrylate, 8-10 parts of glycidol, 0.01-0.02 part of lithium methoxide and 1-2 parts of triethylamine.Epoxide ring-opening is promoted under the action of the triethylamine, the glass fiber is woven in a mixed manner, so that the composite strength of the glass fiber and a polyester fiber is improved,and the mechanical stability and toughness of a finished fiber material are enhanced.

The invention discloses epoxy metal paint and a preparation method thereof. The epoxy metal paint comprises, by weight, 130-200 parts of epoxy resin E44, 2-3 parts of 3-aminopropyl trimethoxy silane,1-2 parts of ammonium dihydrogen phosphate, 1-2 parts of benzotriazole, 2-3 parts of stearate, 0.01-0.02 part of lead oxide phosphite hydrate, 4-6 parts of pentaerythritol, 16-20 parts of methyl methacrylate, 10-13 parts of glycidol, 0.1-0.2 part of lithium methoxide, 1-2 parts of polysorbate, 0.8-2 parts of boron trifluoride diethyl etherate and 10-15 parts of polypyrrole. Ammonium dihydrogen phosphate serves as a catalyst, and epoxide ring-opening is achieved at high temperature, so that the dispersion compatibility of all the raw materials is achieved; meanwhile, the anti-corrosion performance and mechanical property of the finished product can be effectively improved by introducing polypyrrole.

The invention provides a determination method for 2-chloromethyl-3,5dimethyl-4-methoxyl pyridine hydrochloride and belongs to an acidimetric non-aqueous titration method. The method comprises the following steps: by taking N-N-dimethylformamide as a titration solvent, a thymol blue absolute methanol solution as an indicator and lithium methoxide as a titrating solution, titrating until the blue color appears and calculating the content of 2-chloromethyl-3,5 dimethyl-4-methoxyl pyridine hydrochloride in a sample according to the consumed volume of the titrating solution, the concentration of the titrating solution and the sampling weighing amount of the sample. The method provided by the invention is one of the mainstream analytical methods. The method has the characteristics of being remarkable in finish point which is easy to judge, good in precision, high in accuracy and the like, can be used for accurately detecting the content of the 2-chloromethyl-3,5 dimethyl-4-methoxyl pyridine hydrochloride, and is simple, economic and rapid.

The invention discloses a phosphatized nano pdu wire harness sheath material. The phosphatized nano pdu wire harness sheath material is prepared from the following raw materials in parts by weight: 35to 40 parts of methyl methacrylate, 25 to 31 parts of glycidol, 140 to 150 parts of polyvinyl chloride, 0.7 to 1 part of a silane coupling agent kh550, 10 to 12 parts of nano silicon dioxide, 3 to 4parts of alkanolamide, 1 to 2 parts of sodium diacetate, 0.8 to 1 part of an amine catalyst, 0.1 to 0.2 part of lithium methoxide, 7 to 9 parts of phosphorus trichloride, 10 to 14 parts of pentaerythritol, 0.8 to 1 part of sucrose acetate isobutyrate, 0.1 to 0.2 part of p-toluene sulfonic acid and 2 to 3 parts of barium stearate. According to the phosphatized nano pdu wire harness sheath material,phosphorus is doped and the material has a certain fireproof and flame-retarding effect, so that the comprehensive performance of a finished-product material is improved.

The invention relates to a preparation method of a benzotriazole ultraviolet light absorber, which comprises the steps of taking 3-[3-(2-H-benzotriazole-2-yl)-4-hydroxy-5-tert-butylphenyl]-methyl propionate and C7-9 alkyl alcohol as raw materials, carrying out transesterification under the action of a catalyst to prepare 3-(2H-benzotriazole-2-yl)-5-(1,1-dimethyl ethyl)-4-hydroxy-C7-9 alkyl ester, wherein the catalyst is lithium methoxide and / or zinc isooctanoate. The product prepared by the method is not easy to oxidize, and the appearance and chromaticity of the product can be ensured; and meanwhile, the problem of acid residues in a reaction system can be effectively solved, and the problem of application limitation of the product due to the acid residues is avoided.

The invention relates to a method for preparing an oxygen cephalosporin compound, and belongs to the technical field of medicine synthesis. In order to solve the technical problems that a synthetic route of a compound is too long and the problem caused by chlorine in the oxygen cephalosporin compound formula I, the aims of simplified process and environment friendliness are fulfilled. The method for preparing the oxygen cephalosporin compound comprises the following steps of: reacting a compound, lithium methoxide and hypochlorous acid tert-butyl ester in a formula II to acquire a compound in a formula III in an organic solvent; and performing condensation reaction on the compound in the formula III and a compound of 1-methyl-5-tetrazole-thione in a formula IV under the condition of existence of an apply acid agent and a condensating agent to acquire corresponding final products. With the adoption of the method, the oxygen cephem and 1-methyl-5-tetrazole-thione are used as initial raw materials, the product is synthetized by means of one-pot, so that the side reaction influence is avoided; the production process is simplified; the product yield is high; the molar yield can reach over 65 percent; and the purity can reach over 95 percent.

The invention discloses a led heat dissipation paint and a preparation method thereof. The led heat dissipation paint is prepared from, by weight, 110-150 parts of high-density polypropylene, 30-40 parts of acrylamide, 1-2 parts of ammonium persulfate, 3-4 parts of gamma- aminopropyltriethoxysilane, 5-8 parts of barium stearate, 20-30 parts of carbon nanotubes, 17-20 parts of waste rubber powder,6-10 parts of methyl methacrylate, 5-8 parts of glycidol, 0.01-0.02 part of lithium methoxide and 0.1-0.2 part of triethylamine. According to the led heat dissipation paint and the preparation methodthereof, carbon nanotube dispersion liquid serves as a reaction solvent, epoxy crosslinking is promoted under the catalysis effect of triethylamine, therefore, dispersion compatibility between the carbon nanotubes and the waste rubber powder is improved, the surface activity is further improved, and thus the mechanical strength and heat dissipation performance of the finished paint are improved.

The invention belongs to the field of organic synthesis, and discloses a preparation method of alkyl alcohol, which comprises the following steps: by taking a bromine compound and an epoxy compound as raw materials, under the conditions that cuprous chloride is taken as a catalyst, tetramethylethylenediamine (TMEDA) is taken as a ligand, lithium methoxide (LiOMe) is taken as alkali and magnesium powder is taken as a reducing agent, carrying out a reaction formula reaction for 12 hours in a tetrahydrofuran solvent at 0 DEG C to obtain an alkyl alcohol compound. Reagents needed by the reaction are low in price, operation is easy, a pre-prepared Grignard reagent does not need to be used, use is convenient, and the synthesis application value is high.

The invention discloses a preparation method of a phenyl-containing compound. The invention provides a preparation method of a compound as shown in a formula I. The preparation method comprises the step of: in the presence of formamide or acetamide and alkali, carrying out amine-ester exchange reaction on a compound as shown in a formula V to obtain the compound as shown in the formula I, wherein the alkali is sodium methoxide, sodium ethoxide or lithium methoxide.

The invention discloses a preparation method of a flomoxef parent nucleus. The preparation method comprises the following preparation steps: in a chloroform solvent, reacting an oxycephem parent nucleus with an organic alkali and phosphorus pentachloride, removing a 7th-site protecting group under the action of methanol, washing the reaction material liquid with water, then conducting drying and filtering, sequentially adding a methanol solution of tert-butyl hypochlorite and lithium methoxide for reaction, washing the reaction material liquid with water again after the reaction is ended, thenconducting drying and filtering, and adding pyridine and difluoromethylthio acetyl chloride for reaction, so as to obtain a final product, namely the flomoxef parent nucleus after the reaction is finished. The preparation method of the flomoxef parent nucleus disclosed by the invention has the advantages that the raw materials are cheap and easy to obtain, the production cost is low, the synthesis operation is simple, the purity of the finished product can reach 99%, and the preparation process is continuous production and is easy to industrialize.

The invention discloses a cefoxitin sodium bulk drug. The cefoxitin sodium bulk drug is composed of the following components: cefalotin, a carbamylation reagent, an organic solvent and frosted particles. A production method for the cefoxitin sodium bulk drug comprises the following steps: pouring the cefalotin and the carbamylation reagent into a reaction vessel for reaction to generate an intermediate product (6R,7S)-3-carbamoyloxymethyl-7-[2-(2-thienyl)acetamido]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-formic acid, and uniformly stirring a mixed solution of the cefalotin and the carbamoylation reagent for 5 minutes by using stirring equipment; and subjecting the intermediate product (6R,7S)-3-carbamoyloxymethyl-7-[2-(2-thienyl)acetamido]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-formic acid to a reaction with a methanol-lithium methoxide solution at a temperature of -70 DEG C to 10 DEG C, and introducing an oxymethyl group to the site 7 so as to generate cefoxitin acid. According to the cefoxitin sodium bulk drug, a mixed cellulose ester microfiltration membrane is adopted for suction filtration, so suction filtration effect is improved, and a medicine processing process is promoted.

The invention discloses a fire-retarding reinforced silicon carbide fiber. The fire-retarding reinforced silicon carbide fiber is composed of, by weight part, 36-40 parts of tetraethoxysilane, 120-140parts of silicon carbide fiber, 4-6 parts of chlorinated paraffin, 1-2 parts of calcium stearate, 13-20 parts of methyl methacrylate, 0.04-0.1 part of lithium methoxide, 18-20 parts of barium hydroxide ocatahydrate, 5-7 parts of tackifier and 1-2 parts of glycidol. The fire-retarding reinforced silicon carbide fiber is high in fire resistance, mechanical performance and tenacity and excellent incomprehensive performance.

The invention relates to a method for preparing an oxygen cephalosporin compound, and belongs to the technical field of medicine synthesis. In order to solve the technical problems that a synthetic route of a compound is too long and the problem caused by chlorine in the oxygen cephalosporin compound formula I, the aims of simplified process and environment friendliness are fulfilled. The method for preparing the oxygen cephalosporin compound comprises the following steps of: reacting a compound, lithium methoxide and hypochlorous acid tert-butyl ester in a formula II to acquire a compound in a formula III in an organic solvent; and performing condensation reaction on the compound in the formula III and a compound of 1-methyl-5-tetrazole-thione in a formula IV under the condition of existence of an apply acid agent and a condensating agent to acquire corresponding final products. With the adoption of the method, the oxygen cephem and 1-methyl-5-tetrazole-thione are used as initial raw materials, the product is synthetized by means of one-pot, so that the side reaction influence is avoided; the production process is simplified; the product yield is high; the molar yield can reach over 65 percent; and the purity can reach over 95 percent.

The invention belongs to the technical field of preparation of ternary material precursors, and in particular relates to a method for directly preparing a lithium zincate modified ternary positive electrode material by using the positive electrode material of a waste lithium battery: separating the positive electrode material from the waste lithium ion battery; using caustic soda The solution is leached and filtered; carbonate is added to the filtrate to obtain lithium carbonate; the filter cake is leached with sulfuric acid to obtain a leaching solution; the molar ratio of nickel, cobalt and manganese in the leaching solution is adjusted; the leaching solution, ammonia solution, and caustic alkali solution are flowed into the reactor , co-precipitate to prepare ternary material precursor; then mix and roast with lithium carbonate to obtain ternary positive electrode material; mix zinc acetate, ethylene glycol plus ether, amines, and lithium methoxide, and add ternary positive electrode material to obtain gel , the ternary cathode material modified by lithium zincate was obtained by roasting. The ternary cathode material modified by lithium zincate of the present invention has strong structural stability, good electrochemical performance, reduced production cost, high product quality, and realizes the directional circulation of nickel, cobalt, manganese and lithium resources.

The invention discloses a synthetic method of lithium methoxide. The method comprises the following steps: Step (1): in an inert gas atmosphere, pouring lithium into methanol, stirring and reacting; and Step (2): after the reaction, concentrating and recycling methanol, and transferring a concentrated residual liquid into a helical ribbon agitator and drying to prepare lithium methoxide, wherein pressure in the helical ribbon agitator is 0.01-0.09 MPa, and temperature in the helical ribbon agitator is 70-80 DEG C. The method has advantages of high production safety, simple operation and high production efficiency. High-quality recycling of methanol can be achieved. The prepared lithium methoxide dry product is not easy for caking, and there is few residual solvent.

The invention relates to a technique for producing lithium alkoxide, which is characterized by comprising the following steps: adding lithium metal into a reactor, dripping ethanol slowly at a temperature of between 20 and 30 DEG C, providing ice water outside the reactor to reduce reaction temperature to between 60 and 80 DEG C in a reaction process, and after finishing dripping the ethanol, keeping the temperature to make full reaction to obtain liquid lithium alkoxide; and then conveying the liquid lithium alkoxide to a closed drier, condensing and drying the liquid lithium alkoxide to obtain solid lithium alkoxide. Reaction of the liquid lithium alkoxide is finished in the reactor firstly, and then materials are conveyed to the drier to be condensed and dried so as to obtain the solidlithium alkoxide. The technique is suitable for industrialized production of lithium methoxide, lithium ethoxide, lithium n-butylate, lithium tert-butylate, lithium isopropoxide or other lithium alkoxides; and the obtained product has high purity.

The invention discloses a cellulose-modified water pollution treatment agent and a preparation method thereof. The cellulose-modified water pollution treatment agent comprises, by weight, 20-34 partsof glycidol, 2-4 parts of aluminum sulfate, 10-13 parts of microcrystalline cellulose, 1-2 parts of lauryl dimethyl amine oxide, 10-14 parts of acrylamide, 0.4-0.6 part of ammonium persulfate, 1-2 parts of diethylenetriamine, 1-2 parts of sodium N-lauroyl sarcosinate, 50-60 parts of tetrabutyl titanate, 20-25 parts of methyl methacrylate and 0.1-0.2 part of lithium methoxide. The water treatment agent of the invention has the advantages of excellent purifying effect, certain adsorption performance for heavy metal and dye sewage, high recycling rate, convenience in recovery, and good environmental protection property.

The invention relates to the technical field of organic synthesis, in particular to a preparation method of 2-(trans-4-n-propyl cyclohexyl) propane-1, 3-diol. The preparation method comprises the steps of (i) carrying out bromination reaction on 4-n-propyl cyclohexanol and phosphorus tribromide to generate 1-bromo-4-n-propyl cyclohexane; (ii) sequentially adding diethyl malonate and 1-bromo-4-n-propyl cyclohexane into the ethanol solution of the lithium methoxide, and carrying out an alkylation reaction to generate 2-(4-n-propyl cyclohexyl)-diethyl malonate; and (iii) sequentially adding 2-(4-n-propyl cyclohexyl)-diethyl malonate, lithium chloride and potassium borohydride into the solvent, carrying out a reduction reaction to generate 2-(4-n-propyl cyclohexyl) propane-1, 3-diol, and carrying out recrystallization to obtain the 2-(trans-4-n-propyl cyclohexyl) propane-1, 3-diol. The method has the advantages of being safe, low in cost, environmentally friendly and suitable for industrial production.

The invention belongs to the technical field of preparation of ternary material precursors, and in particular relates to a method for preparing a lithium aluminate modified ternary positive electrode material based on a waste lithium battery positive electrode material: separating the waste lithium ion battery from the positive electrode material; using a caustic alkali solution Leaching and filtering; adding carbonate to the filtrate to obtain lithium carbonate; leaching the filter cake with sulfuric acid to obtain a leaching solution; adjusting the molar ratio of nickel, cobalt and manganese in the leaching solution to obtain an adjusting solution; In the reaction kettle, co-precipitate to prepare the ternary material precursor; then mix and roast with lithium carbonate to obtain the ternary positive electrode material; add aluminum sec-butoxide, lithium methoxide, ternary The positive electrode material is reacted and calcined to obtain a lithium aluminate modified ternary positive electrode material. The ternary cathode material of the invention has good structural stability and good electrochemical performance, reduces production cost, has high product quality, and realizes directional circulation of nickel-cobalt-manganese-lithium resources.

The invention discloses a 4-methyl-4-phenylcyclopentenone compound and a preparation method thereof. The preparation method comprise the following steps: under an inert gas atmosphere and stirring conditions, mixing 0.18-0.22 mmol of methyl ethynyl ketone, 0.38-0.42 mmol of p-toluenesulfonylhydrazone, 0.018-0.022 mmol of copper hydroxide, and 0.8-1.2 mmol of lithium methoxide, adding 3-5 mL of toluene and 3.5-3.8 [mu]L of water into the mixed solution to obtain a reaction solution, performing heating to 95-105 DEG C and carrying out a reaction for 12-24 h, removing an insoluble solid by filtration after the reaction is completed, and performing vacuum distillation and concentration separation on the obtained solution to obtain the target product 4,4-disubstituted cyclopentenone. The preparation method has simple required process conditions and mild reaction conditions, 4,4-disubstituted cyclopentenone derivatives can be effectively obtained, and the reaction has relatively good substrate applicability and functional group tolerance. At the same time, the carbon-carbon triple bond insertion cleavage method is used for the first time to prepare 4-methyl-4-phenylcyclopentenone.

The invention discloses a preparation method of latamoxef mother nucleus, comprising the following preparation steps: oxacephem mother nucleus, which is used as a raw material, reacts with 1-methyl-5-mercaptotetrazole to prepare (001); 7 protective groups are removed from (001) to prepare (002); and (002) reacts with chlorine and lithium methoxide to prepare the final product latamoxef mother nucleus. The latamoxef mother nucleus preparation method disclosed in the invention has advantages of low cost, simple synthetic operation and easy industrialization. In addition, the product purity (HPLC) can reach 99%. The preparation method has great advantages in the aspect of purity.