CN213037686U - Continuous production system of metadiphenylacetone - Google Patents
Continuous production system of metadiphenylacetone Download PDFInfo
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- CN213037686U CN213037686U CN202021492882.5U CN202021492882U CN213037686U CN 213037686 U CN213037686 U CN 213037686U CN 202021492882 U CN202021492882 U CN 202021492882U CN 213037686 U CN213037686 U CN 213037686U
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Abstract
The utility model relates to a serialization production system of meta-diphenyl acetone belongs to organic synthesis technical field. Including tetrahydrofuran metering tank, chlorobenzene metering tank and grignard reagent cauldron, grignard reagent cauldron passes through the grignard reagent conveyer pipe and links to each other with grignard reaction cauldron, and grignard reaction cauldron passes through the glycol conveyer pipe and links to each other with the glycol metering tank, and the glycol metering tank passes through the pipeline and links to each other with the quenching cauldron, still is connected with hydrochloric acid metering tank, sulphuric acid metering tank and methyl alcohol metering tank on the quenching cauldron. Metadiphenylacetone's serialization production system, realized metadiphenylacetone's serialization, industrial production, factor of safety is high, equipment connection relation reasonable in design, the metadiphenylacetone purity and the yield of production are high.
Description
Technical Field
The utility model relates to a serialization production system of meta-diphenyl acetone belongs to organic synthesis technical field.
Background
The pure product of the metadiphenylacetone is colorless solid, the industrial product is yellow crystal, and the metadiphenylacetone can be used as an intermediate for producing anticoagulant rodenticide sodium salt, diphacinone and chlorratine, and can also be used as a medical intermediate such as prostaglandin I2 agonist and the like.
In the prior art, the preparation of the metadiphenylacetone mainly adopts the following route:
(1) introducing nitrogen into a dry three-neck flask, performing displacement for three times, adding a phenylmagnesium chloride tetrahydrofuran solution, placing in an ice-water bath, and controlling the internal temperature to be about 0 ℃;
(2) dropwise adding an ethyl lactate-tetrahydrofuran solution under the stirring state, removing the ice bath after the dropwise adding is finished, replacing the ice bath with an oil bath, slowly heating to the reflux temperature, and refluxing for 2 hours;
(3) removing the oil bath, cooling to 0 ℃ with ice water, and dropwise adding 10% dilute hydrochloric acid solution under rapid stirring;
(4) separating, separating organic layer, washing water phase with dichloromethane twice, combining organic phase, drying, and concentrating;
(5) adding 20% sulfuric acid into the obtained concentrated phase, heating to 90 deg.C, refluxing for 3-4 hr, and separating;
(6) adding water into the organic phase, adjusting the pH to 7 with liquid alkali, washing with water, and concentrating the obtained organic phase to obtain a viscous product;
(7) the methanol is recrystallized to obtain white solid, namely the metadiphenyl acetone.
In the synthesis method, the phenylmagnesium chloride tetrahydrofuran solution adopted in the step (1) needs to be prepared in situ, the existing preparation method of the Grignard reagent has strict requirements on reaction conditions, and the reaction is not easy to control. The Grignard reaction usually has large heat release amount, the heat release of the reaction is controlled by controlling the dropping speed of the halogenated hydrocarbon, the production cycle of preparing the Grignard reagent by batch reaction is long, the Grignard reagent is usually sensitive to air and water, and if a large amount of Grignard reagents prepared by batch reaction cannot be used in time, the storage risk can be increased, and the storage cost can be increased.
And (3) adding 10% dilute hydrochloric acid to quench, washing the separated water phase twice with dichloromethane, combining the water phase and the organic phase, drying and concentrating the organic phase for subsequent reaction, performing drying and concentrating processes on the organic phase, wasting time and labor, wherein the evaporated solvent contains a large amount of tetrahydrofuran, the quenching process is complicated, and more equipment is needed.
And (3) adding sulfuric acid to perform a dehydration reaction in the step (5), and after the reaction is finished, performing liquid separation, wherein the liquid separation is to add water to the organic phase, adjust the pH value to 7 with liquid alkali, wash the organic phase with water, concentrate the obtained organic phase, and recrystallize methanol to obtain a white solid. The recrystallization process is complicated, and sulfuric acid needs to be added with a large amount of liquid alkali to carry out neutralization reaction in the reaction process, so that a large amount of wastewater is generated, and the wastewater treatment pressure is increased.
In summary, the above method is only suitable for synthesizing the metadiphenylacetone in a laboratory, the process flow is complex, the synthesis route is long, the requirement on production equipment is high, the produced wastewater and waste gas are more, and the continuous production cannot be realized, so a set of system capable of realizing the continuous production of the metadiphenylacetone needs to be explored.
SUMMERY OF THE UTILITY MODEL
The utility model aims at: the continuous production system of the meta-diphenylacetone can realize continuous and industrial production of the meta-diphenylacetone, has high safety factor, reasonable design of equipment connection relation, and high purity and yield of the produced meta-diphenylacetone.
Partial diphenyl acetone's serialization production system, including tetrahydrofuran metering tank, chlorobenzene metering tank and grignard reagent cauldron, grignard reagent cauldron passes through the grignard reagent conveyer pipe and links to each other with grignard reaction cauldron, grignard reaction cauldron passes through the glycol conveyer pipe and links to each other with the glycol metering tank, and the glycol metering tank passes through the pipeline and links to each other with quenching cauldron, still is connected with hydrochloric acid metering tank, sulphuric acid metering tank and methyl alcohol metering tank on the quenching cauldron.
Wherein:
tetrahydrofuran metering tank, chlorobenzene metering tank and magnesium bits feeding device link to each other with grignard reagent cauldron feed inlet through the pipeline respectively, and low pressure nitrogen gas conveyer pipe links to each other with grignard reagent cauldron air inlet, and grignard reagent cauldron one end is passed through the pipeline and is linked to each other with emergent cauldron, and grignard reagent cauldron upper portion gas outlet passes through the pipeline and links to each other with first condensation reflux unit.
The Grignard reagent conveying pipe is inserted into the Grignard reagent kettle from top to bottom, the pipe orifice of the Grignard reagent conveying pipe faces downwards, and the distance from the pipe orifice of the Grignard reagent conveying pipe to the bottom of the Grignard reagent kettle is calculated according to the difference of the size, the shape and the diameter of the Grignard reagent kettle, so that after the Grignard reagent is transferred each time, the volume of the remaining Grignard reagent is 3-10% of the total volume of the reaction liquid for producing the Grignard reagent circularly each time.
The gas inlet of the Grignard reaction kettle is connected with the low-pressure nitrogen conveying pipe, the feed inlet of the Grignard reaction kettle is connected with the lactate metering tank through a pipeline, and the gas outlet at the upper part of the Grignard reaction kettle is connected with the second condensation reflux device through a pipeline.
The solution contained in the lactate metering tank is one of ethyl lactate, methyl lactate, propyl lactate, isopropyl lactate or butyl lactate.
The hydrochloric acid metering tank and the sulfuric acid metering tank are combined through a pipeline and then connected with the feeding port of the quenching kettle, the methanol metering tank and the glycol metering tank are combined through a pipeline and then connected with the feeding port of the quenching kettle, and the low-pressure nitrogen conveying pipe is connected with the air inlet of the quenching kettle.
The operating principle and the process of the continuous production system of the metadiphenyl acetone are as follows:
firstly, adding a prefabricated Grignard reagent serving as an initiator at the bottom of a Grignard reagent kettle, covering the prefabricated Grignard reagent with a tetrahydrofuran solution, then adding chlorobenzene, tetrahydrofuran and magnesium chips into the Grignard reagent kettle through a chlorobenzene metering tank, a tetrahydrofuran metering tank and a magnesium chip feeding device respectively through pipelines, conveying nitrogen to the Grignard reagent kettle through a low-pressure nitrogen conveying pipe, and preparing the Grignard reagent under the condition of ensuring that the Grignard reagent kettle is in an anhydrous and anaerobic environment.
The Grignard reagent prepared by the Grignard reagent kettle is conveyed to the Grignard reaction kettle through the Grignard reagent conveying pipe, the Grignard reagent is extracted from the upper liquid level to be transferred to the Grignard reaction kettle by adopting the Grignard reagent conveying pipe, because the upper liquid level of the Grignard reagent kettle is the Grignard reagent clear liquid prepared by the Grignard reaction, and the lower liquid level has a little of impurities such as salt or magnesium chips. Calculating the position from the pipe orifice of the pipeline to the position below the liquid level according to the size and the shape of the Grignard reagent kettle, and ensuring that the volume of the residual liquid is 3-10% of the total volume of the reaction liquid of each cycle of Grignard reaction after the Grignard reagent is transferred; the remaining grignard reagent was used as an initiator for the next batch of grignard reactions.
Adding lactate into a Grignard reaction kettle through a lactate metering tank, reacting the lactate with a conveyed Grignard reagent at 95-105 ℃ for 2-3 hours in the Grignard reaction kettle to prepare a 1, 1-diphenyl-1, 2-propanediol solution, conveying the prepared 1, 1-diphenyl-1, 2-propanediol solution to a diol metering tank through a diol conveying pipe, adding the diol metering tank into a quenching kettle through a pipeline for reaction, cooling to 0 ℃, adding a dilute hydrochloric acid solution into the quenching kettle from a hydrochloric acid metering tank through a pipeline for quenching, standing for liquid separation after the reaction is finished, discharging an organic phase at an upper layer, a water phase at a lower layer, and discharging the separated water phase into a wastewater pool through a pipeline at the lower part of the quenching kettle.
The separated organic phase is directly distilled to remove the solvent without being dried, and the distilled solvent not only contains tetrahydrofuran solvent, but also contains benzene, methanol and the like, which are byproducts of the Grignard reaction; the distilled solvent is sequentially passed through a molecular sieve drying tower and an anhydrous calcium chloride drying tower to remove water and methanol (to form a calcium chloride-methanol complex), then is distilled by a distillation tower, and the fraction is directly introduced into a Grignard reagent kettle to be used for producing the next batch of Grignard reagent.
And then adding sulfuric acid with the concentration of 20-25% into the quenching kettle through a sulfuric acid metering tank, dehydrating for 3-4 hours at the temperature of 90-95 ℃, cooling to 60-70 ℃, separating liquid while the sulfuric acid is hot, discharging a water phase through a pipeline, adding methanol into an organic phase of the quenching kettle through a methanol metering tank, and recrystallizing to prepare the metadiphenylacetone.
The lower water phase is sulfuric acid with the concentration less than 20-25 wt%, and is recycled after part of sulfuric acid is additionally added.
Compared with the prior art, the utility model beneficial effect who has is:
(1) partial diphenyl acetone's serialization production system, in the grignard reagent cauldron, the preparation of first batch grignard reagent adopts prefabricated grignard reagent as initiating agent, violent exothermic in the short time of having avoided reaction initial stage grignard reagent preparation in-process, and the grignard reagent of preparation is through orificial position under the control liquid level, the grignard reagent who guarantees the preparation can be used at any time, when having realized grignard reagent serialization production, the grignard reagent who has still reserved 3-10% volume for next batch chromium reaction is used for the initiating agent.
(2) Partial diphenyl acetone's serialization production system, adopt low pressure nitrogen conveyer pipe to carry nitrogen gas for grignard reagent cauldron and grignard reaction cauldron, grignard reagent cauldron and the grignard reaction cauldron that use in the assurance production process are in under anhydrous anaerobic state all the time, have shortened operating time greatly, have reduced manufacturing cost.
(3) Metadiphenylacetone's serialization production system, add reaction liquid through the glycol conveyer pipe in the quenching cauldron that contains dilute hydrochloric acid, one can guarantee that reation kettle is in anhydrous anaerobic state, secondly because add dilute hydrochloric acid in the glycol, add the order and invert, the phenomenon that salify deposits in the twinkling of an eye can appear, whole system is gelatineous, is difficult to the stirring.
(4) Metadiphenylacetone's serialization production system, realized metadiphenylacetone's serialization, industrial production, factor of safety is high, equipment connection relation reasonable in design, the metadiphenylacetone purity and the yield of production are high.
Drawings
FIG. 1 is a schematic diagram of a continuous production system for meta-diphenylacetone.
In the figure: 1. a tetrahydrofuran metering tank; 2. a chlorobenzene metering tank; 3. a low-pressure nitrogen delivery pipe; 4. a magnesium scrap feeding device; 5. a Grignard reagent kettle; 6. an emergency kettle; 7. a Grignard reagent delivery tube; 8. a Grignard reaction kettle; 9. a lactate metering tank; 10. a quenching kettle; 11. a glycol delivery pipe; 12. a glycol metering tank; 13. a hydrochloric acid metering tank; 14. a sulfuric acid metering tank; 15. a methanol metering tank; 16. a first condensing reflux unit; 17. a second condensing reflux device; 18. a molecular sieve drying tower; 19. an anhydrous calcium chloride drying tower; 20. a distillation column.
Detailed Description
The present invention will be further described with reference to the following examples.
Example 1
Embodiments of the present invention are further described below with reference to the accompanying drawings: as shown in fig. 1, the continuous production system of metadiphenylacetone described in this embodiment 1 includes a tetrahydrofuran metering tank 1, a chlorobenzene metering tank 2, and a grignard reagent kettle 5, the grignard reagent kettle 5 is connected to a grignard reaction kettle 8 through a grignard reagent delivery pipe 7, the grignard reaction kettle 8 is connected to a diol metering tank 12 through a diol delivery pipe 11, the diol metering tank 12 is connected to a quenching kettle 10 through a pipeline, and the quenching kettle 10 is further connected to a hydrochloric acid metering tank 13, a sulfuric acid metering tank 14, and a methanol metering tank 15.
Wherein:
tetrahydrofuran metering tank 1, chlorobenzene metering tank 2 and magnesium bits feeding device 4 link to each other with 5 feed inlets of grignard reagent cauldron through the pipeline respectively, and low pressure nitrogen gas conveyer pipe 3 links to each other with 5 air inlets of grignard reagent cauldron, and 5 one ends of grignard reagent cauldron pass through the pipeline and link to each other with emergent cauldron 6, and 5 upper portion gas outlets of grignard reagent cauldron pass through the pipeline and link to each other with first condensing reflux unit 16.
The Grignard reagent conveying pipe 7 is inserted into the Grignard reagent kettle 5 from top to bottom, the pipe orifice of the Grignard reagent conveying pipe 7 faces downwards, and the distance from the pipe orifice of the Grignard reagent conveying pipe 7 to the bottom of the Grignard reagent kettle 5 is calculated according to the difference of the size, the shape and the diameter of the Grignard reagent kettle 5, so that after the Grignard reagent is transferred each time, the volume of the remaining Grignard reagent is 3-10% of the total volume of the reaction liquid for producing the Grignard reagent in each cycle.
An air inlet of the Grignard reaction kettle 8 is connected with the low-pressure nitrogen conveying pipe 3, a feed inlet of the Grignard reaction kettle 8 is connected with the lactate metering tank 9 through a pipeline, and an air outlet at the upper part of the Grignard reaction kettle 8 is connected with the second condensation reflux device 17 through a pipeline.
The solution contained in the lactate metering tank 9 is one of ethyl lactate, methyl lactate, propyl lactate, isopropyl lactate, or butyl lactate.
The hydrochloric acid metering tank 13 and the sulfuric acid metering tank 14 are combined through a pipeline at the lower discharge port and then connected with the feed port of the quenching kettle 10, the methanol metering tank 15 and the glycol metering tank 12 are combined through a pipeline at the lower discharge port and then connected with the feed port of the quenching kettle 10, and the low-pressure nitrogen conveying pipe 3 is connected with the air inlet of the quenching kettle 10.
The working principle and the process of the continuous production system of the metadiphenylacetone described in the embodiment 1 are as follows:
firstly, adding a prefabricated Grignard reagent serving as an initiator at the bottom of a Grignard reagent kettle 5, covering the prefabricated Grignard reagent with a tetrahydrofuran solution, then adding chlorobenzene, tetrahydrofuran and magnesium chips into the Grignard reagent kettle 5 through pipelines respectively by a chlorobenzene metering tank 2, a tetrahydrofuran metering tank 1 and a magnesium chip feeding device 4, conveying nitrogen to the Grignard reagent kettle 5 through a low-pressure nitrogen conveying pipe 3, and preparing the Grignard reagent under the condition of ensuring that the Grignard reagent kettle 5 is in an anhydrous and anaerobic environment.
The Grignard reagent prepared in the Grignard reagent kettle 5 is conveyed to the Grignard reaction kettle 8 through the Grignard reagent conveying pipe 7, the Grignard reagent is extracted from the upper liquid level to be transferred to the Grignard reaction kettle 8 through the Grignard reagent conveying pipe 7, the upper liquid level of the Grignard reagent kettle 5 is the Grignard reagent clear liquid prepared by the Grignard reaction, and the lower liquid level has a little impurities such as salt or magnesium chips. Calculating the position from the pipe orifice of the pipeline to the position below the liquid level according to the size and the shape of the Grignard reagent kettle 5, wherein after the Grignard reagent is transferred, the volume of the residual liquid is 8 percent of the total volume of the reaction liquid of each cycle of the Grignard reaction; the remaining grignard reagent was used as the initiator for the next batch of grignard reactions.
Lactate is added into a Grignard reaction kettle 8 through a lactate metering tank 9, the lactate reacts with conveyed Grignard reagents at 105 ℃ for 2.5 hours in the Grignard reaction kettle 8 to prepare 1, 1-diphenyl-1, 2-propanediol solution, the prepared 1, 1-diphenyl-1, 2-propanediol solution is conveyed to a diol metering tank 12 through a diol conveying pipe 11, then the solution is added into a quenching kettle 10 through a pipeline for reaction, the temperature is reduced to 0 ℃, dilute hydrochloric acid solution is added into the quenching kettle 10 through a hydrochloric acid metering tank 13 through a pipeline for quenching, after the reaction is finished, the solution is kept stand for separation, an organic phase is at the upper layer, an aqueous phase is at the lower layer, and the separated aqueous phase is discharged into a wastewater pool through a pipeline at the lower part of the quenching kettle 10.
The separated organic phase is directly distilled to remove the solvent without being dried, and the distilled solvent not only contains tetrahydrofuran solvent, but also contains benzene, methanol and the like, which are byproducts of the Grignard reaction; the distilled solvent is sequentially passed through a molecular sieve drying tower and an anhydrous calcium chloride drying tower to remove water and methanol (to form a calcium chloride-methanol complex), then is distilled by a distillation tower, and the fraction is directly introduced into a Grignard reagent kettle to be used for producing the next batch of Grignard reagent.
Then adding 25% sulfuric acid into the quenching kettle 10 through a sulfuric acid metering tank 14, dehydrating for 3.5 hours at the temperature of 92 ℃, then cooling to 65 ℃, separating liquid while hot, discharging a water phase through a pipeline, adding methanol into an organic phase of the quenching kettle 10 through a methanol metering tank 15, and recrystallizing to prepare the metadiphenylacetone.
The lower water phase is sulfuric acid with the concentration less than 20-25 wt%, and is recycled after part of sulfuric acid is additionally added.
And methanol is directly added into the organic phase for recrystallization, water is not needed to be added firstly, the pH value is adjusted to be 7 by liquid alkali, water washing and concentration are carried out, and methanol is added for recrystallization finally, so that the recrystallization process is greatly simplified, and the prepared product has high purity and yield.
Claims (6)
1. A continuous production system of metadiphenylacetone is characterized in that: including tetrahydrofuran metering tank (1), chlorobenzene metering tank (2) and grignard reagent cauldron (5), grignard reagent cauldron (5) link to each other with grignard reaction cauldron (8) through grignard reagent conveyer pipe (7), grignard reaction cauldron (8) link to each other with glycol metering tank (12) through glycol conveyer pipe (11), glycol metering tank (12) link to each other with quenching cauldron (10) through the pipeline, still be connected with hydrochloric acid metering tank (13) on quenching cauldron (10), sulphuric acid metering tank (14) and methyl alcohol metering tank (15).
2. The continuous production system of metadiphenylacetone according to claim 1, characterized in that: tetrahydrofuran metering tank (1), chlorobenzene metering tank (2) and magnesium bits feeding device (4) link to each other with grignard reagent cauldron (5) feed inlet through the pipeline respectively, and low pressure nitrogen gas conveyer pipe (3) link to each other with grignard reagent cauldron (5) air inlet, and grignard reagent cauldron (5) one end is passed through the pipeline and is linked to each other with emergent cauldron (6), and grignard reagent cauldron (5) upper portion gas outlet passes through the pipeline and links to each other with first condensation reflux unit (16).
3. The continuous production system of metadiphenylacetone according to claim 1, characterized in that: the Grignard reagent conveying pipe (7) is inserted into the Grignard reagent kettle (5) from top to bottom, the pipe orifice of the Grignard reagent conveying pipe (7) faces downwards, and the distance from the pipe orifice of the Grignard reagent conveying pipe (7) to the bottom of the Grignard reagent kettle (5) is calculated according to the difference of the size, the shape and the diameter of the Grignard reagent kettle (5), so that after the Grignard reagent is transferred each time, the volume of the remaining Grignard reagent is 3-10% of the total volume of the reaction liquid for producing the Grignard reagent in each cycle.
4. The continuous production system of metadiphenylacetone according to claim 1, characterized in that: an air inlet of the Grignard reaction kettle (8) is connected with the low-pressure nitrogen conveying pipe (3), a feed inlet of the Grignard reaction kettle (8) is connected with the lactate metering tank (9) through a pipeline, and an air outlet at the upper part of the Grignard reaction kettle (8) is connected with the second condensation reflux device (17) through a pipeline.
5. The continuous production system of metadiphenylacetone according to claim 4, characterized in that: the solution contained in the lactate metering tank (9) is one of ethyl lactate, methyl lactate, propyl lactate, isopropyl lactate or butyl lactate.
6. The continuous production system of metadiphenylacetone according to claim 1, characterized in that: the hydrochloric acid metering tank (13) and the lower discharge port of the sulfuric acid metering tank (14) are combined through a pipeline and then are connected with the feed port of the quenching kettle (10), the methanol metering tank (15) and the lower discharge port of the glycol metering tank (12) are combined through a pipeline and then are connected with the feed port of the quenching kettle (10), and the low-pressure nitrogen conveying pipe (3) is connected with the air inlet of the quenching kettle (10).
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