- Method for synthesizing P-bromomethyl isobenzopropionic acid
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The invention provides a method for synthesizing p-bromomethyl isobenzopropionic acid, and relates to the technical field of organic synthesis. The synthesis method disclosed by the invention comprises the synthesis of isobenzoates. Vilsmeier Reagent preparation method comprises the following steps: synthesizing aldehyde isopropylparaben, synthesizing methyl isopropylbenzene, separating and purifying bromomethyl isobenzopropionic acid and, and the like. The final para-position selectivity of the method can reach 90 - 97%, and the three-waste yield is greatly reduced.
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- Preparation method of p-bromomethyl isophenylpropionic acid
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The invention belongs to the field of synthesis of drug intermediates, and particularly relates to a preparation method of p-bromomethyl isophenylpropionic acid, which comprises the following steps: A, synthesis of alpha-methyl benzyl chloride: carrying out addition reaction on styrene serving as a raw material and hydrogen chloride gas in an organic solvent to generate alpha-methyl benzyl chloride, B, synthesis of 2-phenylpropionic acid: preparing alpha-methyl benzyl chloride into a Grignard solution through a Grignard reaction, the Grignard solution and carbon dioxide gas are subjected to acarboxylation reaction to generate a carboxylation solution, and the carboxylation solution is hydrolyzed to obtain 2-phenylpropionic acid, and C, synthesis of p-bromomethyl isophenylpropionic acid: carrying out bromomethylation reaction of 2-phenylpropionic acid, hydrobromic acid and polyformaldehyde so that p-bromomethyl isophenylpropionic acid is generated. The preparation method of p-bromomethyl isophenylpropionic acid provided by the invention has the advantages of cheap and accessible raw materials and simple technique, and is suitable for industrial production.
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- Production method of 2-(4-bromomethyl phenyl)propionic acid
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The invention discloses a production method of 2-(4-bromomethyl phenyl)propionic acid. An adopted ionic liquid catalyst can be recycled and used, no molten aluminum trichloride is generated, a material does not need to be washed for multiple times, only layered extraction needs to be conducted, then a required product can be obtained, aluminum trichloride and triethanolamine salt ionic liquid is used, thus environmentally friendliness is achieved, the cost is also saved, and that is, an original cumbersome process is simplified. An original bromination reaction in a glass kettle is changed toa cooling glass pipeline circulation-type bromination reaction in the kettle, through the glass pipeline type reaction, the contact area of the material and light is increased, through circulation, the situation that the material is gathered on the illumination surface, and consequently light illumination is affected is avoided, thus the reaction efficiency is higher, the reaction time is shortened, the occurrence of a side reaction is controlled, and the product purity is higher.
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Paragraph 0017; 0022; 0028; 0029
(2020/03/06)
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- Novel synthesizing method of 2-(4-bromomethyl)phenylpropionic acid
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The invention belongs to the field of preparation of intermediates in chemical engineering, and particularly relates to a novel synthesizing method of 2-(4-bromomethyl)phenylpropionic acid. The novelsynthesizing method comprises the following steps of using 4-methyl acetophenone as the raw material; performing reduction, chlorinating and cyaniding, so as to obtain 2-(4-methyl)phenylpropionitrile;hydrolyzing, and brominating, so as to obtain the 2-(4-bromomethyl)phenylpropionic acid. The novel synthesizing method has the advantages that the yield rate is increased, and the cost of raw material is low; the novel synthesizing method is suitable for industrialized production.
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- Liquid-phase circulation preparation method for 2-(4-bromomethylphenyl)propionic acid
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The invention discloses a liquid-phase circulation preparation method for 2-(4-bromomethylphenyl)propionic acid. The liquid-phase circulation preparation method comprises the following steps: feedinghydrobromic acid, paraformaldehyde, 2-phenylpropionic acid, a solvent and a Lewis acid catalyst in a bromoethylation reactor as reaction materials; adding water into a hydrogen bromide gas generator,adding phosphorus tribromide drop by drop, and allowing generated hydrogen bromide gas to pass through a buffer device and then to enter the bromoethylation reactor; heating the bromoethylation reactor to 60-80 DEG C, conveying a liquid phase in the reactor to a spray thrower through a liquid-phase circulation pump, spraying the liquid phase into a filler by the spray thrower so as to allow the liquid phase and the hydrogen bromide gas to fully contact in the filler, and carrying out reaction-absorption to achieve liquid-phase circulation; and after a reaction is completed, subjecting a reaction liquid in the bromoethylation reactor to post-treatment so as to obtain 2-(4-bromomethylphenyl)propionic acid. The method has the advantages of small amount of waste gas, waste water and industrialresidues, low cost and environment friendliness when applied to preparation of 2-(4-bromomethylphenyl)propionic acid.
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Paragraph 0063-0075; 0077; 0089-0095; 0097-0099; 0101-0103
(2019/01/22)
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- Gas-phase circulation preparation method for 2-(4-bromomethylphenyl)propionic acid
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The invention discloses a gas-phase circulation preparation method for 2-(4-bromomethylphenyl)propionic acid. The gas-phase circulation preparation method comprises the following steps: feeding hydrobromic acid, paraformaldehyde and 2-phenylpropionic acid in a bromoethylation reactor and adding a solvent and a Lewis acid catalyst as reaction materials; adding water into a hydrogen bromide gas generator, adding phosphorus tribromide drop by drop, and allowing generated hydrogen bromide gas to enter a buffer device; after heating of the bromoethylation reactor, allowing a gas phase of the reaction materials to enter a condenser for condensation, combining uncondensed gas with hydrogen bromide gas discharged from the buffer device, then allowing the obtained gas mixture to enter a gas circulation pump, and conveying the gas mixture to the bottom of the bromoethylation reactor by the gas circulation pump so as to realize gas-phase circulation; and after a reaction is completed, subjectinga reaction liquid in the bromoethylation reactor to post-treatment so as to obtain 2-(4-bromomethylphenyl)propionic acid. The method has the advantages of small amount of waste gas, waste water and industrial residues, low cost and environment friendliness when applied to preparation of 2-(4-bromomethylphenyl)propionic acid.
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Page/Page column 8-12
(2019/01/24)
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- Synthetic method of 2-(4-bromomethyl)phenylpropionic acid
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The invention provides a synthetic method of 2-(4-bromomethyl)phenylpropionic acid. The synthetic method comprises the following steps: (1) by taking 2-phenylpropionic acid as a raw material, bromineionic liquid as a reaction solvent, and formaldehyde and hydrogen bromide as bromoethylation reagents, enabling a reaction at a certain temperature for a certain period of time; (2) extracting 2-(4-bromomethyl)phenylpropionic acid from the product of the step (1) by use of an organic solvent, washing the extract containing 2-(4-bromomethyl)phenylpropionic acid with water, performing concentrationto obtain a 2-(4-bromomethyl)phenylpropionic acid crude product, and recrystallizing the crude product by a solvent to obtain a 2-(4-bromomethyl)phenylpropionic acid quality product; and (3) removingmost water and the organic solvent in bromine ionic liquid after extraction.
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Paragraph 0024; 0025; 0026; 0027; 0028; 0029; 0030; 0031
(2018/03/26)
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- Preparation method of 2-(4-bromomethyl)phenyl propionic acid
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The invention discloses a preparation method of 2-(4-bromomethyl)phenyl propionic acid. The preparation method includes the steps of: performing a reaction to a compound (I) (4-methylstyrene) with hydrogen halide to prepare a compound (II), performing a Grignard reaction and a carboxylation reaction to the compound (II) to obtain a compound (IV), and performing a bromination reaction to obtain a compound (V) (2-(4-bromomethyl)phenyl propionic acid), wherein a byproduct compound (VI) is subjected to a debromination reaction to obtain the compound (V) (2-(4-bromomethyl)phenyl propionic acid). The method is low in cost, has simple operations, is high in yield, is environment-friendly, and is suitable for industrial production.
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Paragraph 0081-0084; 0089-0092; 0105-0108
(2018/01/11)
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- Method for preparing loxoprofen sodium
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The invention relates to the technical field of organic synthesis, in particular to a method for preparing loxoprofen sodium. The invention provides a compound with the structure shown in formula 5 and a preparation method and application of the compound, (the formula is defined in the description). The loxoprofen sodium obtained according to the scheme is high in purity, high in industrialized operation, and good in application prospect.
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- Pipelization preparation method and device for 2-(4-bromomethylphenyl)propionic acid
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The invention discloses a pipelization preparation method and device for 2-(4-bromomethylphenyl)propionic acid and belongs to the technical field of pharmaceuticals. On one hand, the invention provides the pipelization preparation device for 2-(4-bromomethylphenyl)propionic acid, and the device comprises two tubular photoreactors internally provided with light sources, two mixers, three storage devices, three metering pumps, two water circulating pumps, two water bath kettles and one crystallization kettle. On the other hand, the invention provides the method for preparing 2-(4-bromomethylphenyl)propionic acid by using the device, and the method is simple in operation, mild in reaction condition, simple in aftertreatment, low in waste gas, waste water and waste residue production, high in atom utilization ratio, low in cost and high in economic benefit and is a green and environment-friendly process suitable for industrial production.
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Paragraph 0031-0048; 0049; 0050; 0051-0054
(2018/04/01)
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- Synthesis method of 4-bromomethyl isophenylpropionic acid
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The invention provides synthesis of 4-bromomethyl isophenylpropionic acid. The synthesis comprises the following steps: toluene and a methylation reagent undergo a reaction to produce isophenylpropionic acid at high temperature under an alkaline effect; carry out acid washing and distillation on a reaction solution to prepare qualified isophenylpropionic acid with purity more than 98 percent, so as to prepare a compound 4-bromomethyl isophenylpropionic acid: carrying out bromomethylation reaction on the qualified product isophenylpropionic acid to produce a compound 4-bromomethyl isophenylpropionic acid reaction solution; dissolving the reaction solution, washing with water, concentrating, washing and centrifuging to obtain a qualified finished product. Compared with the prior art, the raw materials are easy to obtain and the cost is low; the synthesis has the advantages of cheap and easily-obtained raw materials, small toxin, low cost, simplicity and convenience for operation and is applicable to industrialization; a few of three wastes are generated, and the wastes are comprehensively utilized and national industrial policies are met.
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Paragraph 0013
(2017/07/19)
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- Method for preparing loxoprofen intermediate
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A method for preparing a loxoprofen intermediate comprises the following steps that 1, on the presence of sodium alkoxide, benzyl cyanide and dimethyl carbonate are subjected to methylation in an organic solvent, and 2-(phenyl cyano) sodium propionate is obtained; 2, 2-(phenyl cyano) sodium propionate and dimethyl sulfate react in an organic solvent to obtain 2-(phenyl cyano) methyl propionate; 4, 2-(phenyl cyano) methyl propionate reacts under the alkaline condition to obtain 2-phenyl propionitrile; 4, 2-phenyl propionitrile is hydrolyzed under the alkaline condition, acid is added for acidizing after the reaction to obtain 2-phenylpropionic acid; 5, 2-phenylpropionic acid, hydrobromic acid and paraformaldehyde are mixed and subjected to a bromine methylation reaction under the acidic condition, and 2-(4-tribromomethyl phenyl) propionic acid is obtained.According to the method, a new synthesis route is designed, product selectivity is good, the purity is high, the conversion rate is high, and few by-products are generated; the raw materials are simple and easy to obtain, the production conditions are mild, the process is simple, production cost is low, and pollution is small.
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- A 2 - (4-bromo methyl phenyl) propionic acid preparation method
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The invention discloses a preparation method of 2-(4-bromomethylphenyl) propionic acid. The preparation method is characterized by comprising a preparation stage of 2-phenyl propionitrile, a preparation stage of 2-phenyl propionic acid and a preparation stage of 2-(4-bromomethylphenyl) propionic acid. The preparation stage of 2-phenyl propionitrile comprises the following steps: mixing benzyl cyanide, dimethyl carbonate and potassium carbonate; heating to 100-300 DEG C and carrying out thermal reaction for 5-50h under the pressure of 0.5-6MPa; and by the end of the reaction, carrying out filter pressing and rinsing to be neutral; distilling to removal excessive dimethyl carbonate; and carrying out high-vacuum rectification to obtain 2-phenyl propionitrile. Compared with the prior art, the preparation method disclosed by the invention has the following advantages and effects that the main raw material is benzyl cyanide which is subjected to methylation, hydrolysis reaction and bromomethylation to finally obtain the finished product; the purity of the finished product is high and the yield is up to 90% or above; and in addition, the preparation method has the advantages of simple production process, low production cost and low environment pollution.
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- Process for the production of benzene derivatives
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The present invention relates to a process for the production of benzene derivatives represented by formula (I), which are useful as intermediates for agricultural chemicals, fine chemical products or pharmaceuticals such as anti inflammatory analgesics. The process includes reacting a compound of chemical formula (II) with a hydroformylating agent and a halogenating agent.
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- A process for the production of benzene derivatives
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The present invention relates to a process for the production of benzene derivatives as compounds of chemical formula ( I ) below which are used as intermediates of agricultural chemical, fine chemical products or pharmaceuticals such as anti inflammatory analgesics. The process for the production of benzene derivatives of present invention expressed in below chemical formula ( I ) is characterized by making reaction between compound of chemical formula ( II ) and hydrofomylating agent under halogenation agent. In chemical formula ( I ) and ( II ), X is halogenic atom, R1& R2are same or different each other, R1is hydrogen atom or low alkyl radical of carbon number 1 ~ 6, R2is hydrogen atom or COOR3, and R3is hydrogen atom or low alkyl radical of carbon number 1 ~ 6.
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- Aryloxypyridines
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Compounds of the formula STR1 wherein Py is a substituted or unsubstituted 2-, 3- or 4-pyridyl, N-oxidized or quaternized pyridyl group; A is a group of the formula (IIIA), (IIIB) or (IIIC) STR2 wherein ALK is straight or branched chain alkylene of 1 to 6 carbon atoms; R1 is a carboxylic acid group, a group which is converted in the human body to a carboxylic acid group or acyl; R2, R3 and R4 are each hydrogen, a carboxylic acid group, a group which is converted in the human body to a carboxylic acid group, acyl, hydroxy, alkoxy, aralkoxy, aryloxy, an esterified hydroxy group, nitro, halogen or amino; May be formulated into pharmaceutical compositions useful for the treatment of hyperglycaemia by combining said compounds with a pharmaceutically acceptable non-toxic inert diluent or carrier. Compounds of the formula STR3 wherein Py is a substituted or unsubstituted 2-, 3- or 4-pyridyl, N-oxidized or quaternized pyridyl group; A is a group of formula (IIIA), (IIIB) or (IIIC) STR4 wherein ALK is straight or branched chain alkylene of 1 to 6 carbon atoms; R1 is a carboxylic acid group, a group which is converted in the human body to a carboxylic acid group or acyl; R2, r3 and R4 are each hydrogen, a carboxylic acid group, a group which is converted in the human body to a carboxylic acid group, hydroxy, alkoxy, aralkoxy, aryloxy, an esterified hydroxy group, nitro, halogen, or amino, Provided that R1 is not methyl, cyano or methoxycarbonyl when Py is 2-pyridyl or 5-ethylpyrid-2-yl and A is [O--CH2 ]and R2, R3 and R4 are hydrogen or halogen, Are novel compounds per se. The compounds and compositions above described are useful for their hypoglycaemic activity and are useful in the treatment of hypoglycaemic conditions such as diabetes milletus.
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