A system for the synthesis of a precision propisometon intermediate

Abstract

The utility model relates to a system for synthesizing precise isopropyl methyl parathion intermediate, its characterized in that: hydrogenation kettle bottom's liquid phase export accesses water washing kettle, water washing kettle bottom's liquid phase export connects third liquid phase pipe and fourth liquid phase pipe and accesses waste water storage tank and distillation kettle respectively, distillation kettle top's gas phase export passes through third gas phase pipe and accesses condenser, distillation kettle bottom's liquid phase export accesses residual liquid bucket, condenser top's gas phase export accesses tail gas treatment device, condenser bottom's liquid phase export passes through sixth liquid phase pipe and seventh liquid phase pipe and accesses solvent recovery tank and intermediate tank respectively, and the liquid phase export of intermediate tank bottom accesses acylation reaction unit. The system not only can produce high-purity precise isopropyl methyl parathion intermediate amine ether, but also can realize high -efficient recovery of toluene solvent, saves production cost. This system operation process is simple, is suitable for large industrial production.

Description

Technical Field

[0001] This utility model belongs to the field of chemical technology equipment, specifically relating to a system for synthesizing the intermediate of metolachlor. Background Technology

[0002] S-metolachlor is an amide-based selective herbicide with a storage stability of over two years at room temperature. It can control a variety of weeds and is widely used in crops such as corn, soybeans, cotton, and rapeseed. It is currently a major type of herbicide with advantages such as broad spectrum of weed control and high efficiency.

[0003] Currently, metolachlor is typically prepared using chemical synthesis methods, with the following process route:

[0004] First, 1-methoxypropyl-2-(2-methyl-6-ethylphenyl)imine (4) is generated by dehydration condensation reaction of 2-methyl-6-ethylaniline (2) and methoxyacetone (3). Then, the imine is selectively hydrogenated in a high-pressure hydrogen atmosphere under the action of a chiral catalyst to synthesize the intermediate product of this patent, (S)-2-methyl-6-ethyl-N-(2-methoxy-1-methylethyl)aniline, i.e., amine ether (5). Finally, amine ether (5) is acylated with chloroacetyl chloride (6) to generate S-metolachlor (1). High-purity S-metolachlor not only has highly efficient herbicidal activity, but also helps to reduce the risk of pesticide residues in crops. Obtaining high-purity S-metolachlor intermediates is a strong guarantee for the production of high-purity final product S-metolachlor. However, existing technologies for synthesizing S-metolachlor intermediate amine ethers often produce products with low purity and are complex to operate, and are not favored by industrial production. Therefore, in view of this situation, there is an urgent need to develop a system for synthesizing high-purity metolachlor intermediate amine ethers to meet the needs of actual industrial production. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a system for synthesizing the intermediate of metolachlor.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a system for synthesizing a mesopropyl acetochlor intermediate, comprising a hydrogenation reactor, a washing reactor, a distillation reactor, and a condenser, characterized in that: the liquid phase outlet at the bottom of the hydrogenation reactor is connected to the washing reactor through a first liquid phase pipe; the second liquid phase pipe at the bottom of the washing reactor is connected to a No. 1 three-way valve; one end of the No. 1 three-way valve is connected to a third liquid phase pipe, and the other end is connected to a fourth liquid phase pipe; the fourth liquid phase pipe is connected to the distillation reactor; the gas phase outlet at the top of the distillation reactor is connected to the condenser through a third gas phase pipe; the gas phase outlet at the top of the condenser is connected to a tail gas treatment device through a fourth gas phase pipe; the liquid phase outlet at the bottom of the condenser is connected to a sixth and a seventh liquid phase pipe through a No. 2 three-way valve; the sixth liquid phase pipe is connected to a solvent recovery tank; the seventh liquid phase pipe is connected to an intermediate tank; and the liquid phase outlet at the bottom of the intermediate tank is connected to an acylation reaction device through an eighth liquid phase pipe.

[0007] The hydrogenation kettle, washing kettle, and distillation kettle are all equipped with a stirrer for uniformly mixing the materials.

[0008] The gas phase outlet at the top of the hydrogenation reactor is connected to the tail gas treatment device through a first gas phase pipe; the gas phase outlet at the top of the water washing reactor is also connected to the tail gas treatment device through a second gas phase pipe.

[0009] The third liquid phase pipe is connected to the wastewater storage tank at its end; the liquid phase outlet at the bottom of the distillation kettle is connected to the residual liquid tank through the fifth liquid phase pipe.

[0010] The bottom side wall of the washing tank is equipped with a tuning fork level switch, which is used to issue an alarm signal when the fork teeth are immersed in the organic phase; the washing tank is connected to the process water inlet pipe and the alkali inlet pipe.

[0011] The second liquid phase tube is equipped with a sight glass for observing the color of the material.

[0012] The principle of this utility model is as follows: Imine is selectively hydrogenated in a high-pressure hydrogen atmosphere using toluene as solvent under the action of a chiral catalyst to synthesize the chiral intermediate (S)-2-methyl-6-ethyl-N-(2-methoxy-1-methylethyl)aniline, namely the amine ether intermediate of S-metolachlor. The crude amine ether is purified by alkali washing and distillation to obtain a high-purity amine ether product. Therefore, the process design includes a hydrogenation reactor, a water washing reactor, and a distillation reactor. Due to the strict temperature requirements of the reactors during the synthesis process, in order to accurately control the reactor temperature, the jackets of the three reactors are equipped not only with steam pipelines and condensate pipelines for heating, but also with circulating cooling water supply pipelines and circulating cooling water return pipelines for cooling. After alkali washing in the water washing reactor, the reactants in the hydrogenation reactor can remove excess water-soluble impurities and some acidic byproducts. After standing in the water washing reactor, the materials separate into layers: the upper layer is the organic phase (amine ether intermediate of S-metolachlor and solvent toluene), and the lower layer is the aqueous phase (wastewater). To effectively separate the organic and aqueous phases, a tuning fork level switch is installed on the bottom side wall of the washing vessel, and a sight glass is installed on the discharge pipe at the bottom of the washing vessel. The aqueous phase in the washing vessel is placed into a wastewater storage tank. When the interface between the organic and aqueous phases in the washing vessel drops to the position of the fork tooth of the tuning fork level switch, the tuning fork level switch will issue an alarm signal because the fork tooth is immersed in the organic phase. At this time, the color of the material in the pipe is observed through the sight glass. When the color of the material changes from colorless to yellow, it indicates that the discharge of the aqueous phase in the washing vessel is complete. The discharge from the washing vessel is then switched to the distillation vessel. The mixture of amine ether and toluene enters the distillation vessel. Utilizing the difference in volatility between the two substances, the solvent toluene and the high-purity S-metolachlor intermediate amine ether are distilled out sequentially. The solvent toluene is sent to the solvent recovery tank for later use, and the S-metolachlor intermediate amine ether is sent to the acylation reaction unit for subsequent reactions.

[0013] The beneficial effects of this utility model are: the overall design is simple, it can be used to produce high-purity metolachlor intermediate amine ether, achieve efficient recovery of solvent toluene, and greatly reduce production costs; it is easy to operate, suitable for large-scale industrial production, and has strong practicality and promotion potential in the same industry. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the present invention.

[0015] In the diagram: A - Hydrogenation vessel, B - Washing vessel, C - Distillation vessel, E - Condenser, V - Intermediate tank, L - Tuning fork level switch, S - Sight glass, X - No. 1 three-way valve, Y - No. 2 three-way valve, 1 - First gas phase pipe, 2 - First liquid phase pipe, 3 - Second gas phase pipe, 4 - Second liquid phase pipe, 5 - Third liquid phase pipe, 6 - Fourth liquid phase pipe, 7 - Third gas phase pipe, 8 - Fifth liquid phase pipe, 9 - Fourth gas phase pipe, 10 - Sixth liquid phase pipe, 11 - Seventh liquid phase pipe, 12 - Eighth liquid phase pipe. Detailed Implementation

[0016] The present invention will be further described in detail below with reference to the embodiments. The embodiments are only used to explain the present invention and are not intended to limit the scope of the present invention.

[0017] Example 1, see Figure 1 A system for synthesizing a methyl methacrylate intermediate includes a hydrogenation reactor A, a washing reactor B, a distillation reactor C, and a condenser E. The system is characterized in that: the liquid phase outlet at the bottom of the hydrogenation reactor A is connected to the washing reactor B via a first liquid phase pipe 2; the second liquid phase pipe 4 at the bottom of the washing reactor B is connected to a first three-way valve X; one end of the first three-way valve X is connected to a third liquid phase pipe 5, and the other end is connected to a fourth liquid phase pipe 6; the fourth liquid phase pipe 6 is connected to the distillation reactor C; the gas phase outlet at the top of the distillation reactor C is connected to the condenser E via a third gas phase pipe 7; the gas phase outlet at the top of the condenser E is connected to a tail gas treatment device via a fourth gas phase pipe 9; the liquid phase outlet at the bottom of the condenser E is connected to a sixth liquid phase pipe 10 and a seventh liquid phase pipe 11 via a second three-way valve Y; the sixth liquid phase pipe 10 is connected to a solvent recovery tank; the seventh liquid phase pipe 11 is connected to an intermediate tank V; and the liquid phase outlet at the bottom of the intermediate tank V is connected to an acylation reaction device via an eighth liquid phase pipe 12.

[0018] The hydrogenation reactor A, the washing reactor B, and the distillation reactor C are all equipped with a stirrer for uniformly mixing the materials.

[0019] The gas phase outlet at the top of the hydrogenation reactor A is connected to the tail gas treatment device through the first gas phase pipe 1; the gas phase outlet at the top of the water washing reactor B is also connected to the tail gas treatment device through the second gas phase pipe 3.

[0020] The third liquid phase pipe 5 is connected to the wastewater storage tank at its end; the liquid phase outlet at the bottom of the distillation kettle C is connected to the residual liquid tank through the fifth liquid phase pipe 8.

[0021] The bottom side wall of the washing tank B is equipped with a tuning fork-type liquid level switch L, which is used to issue an alarm signal when the fork teeth are immersed in the organic phase; the washing tank B is connected to the process water inlet pipe and the alkali inlet pipe.

[0022] The second liquid phase tube 4 is equipped with a sight glass S for observing the color of the material.

[0023] The work process is as follows: (1) Add a fixed amount of imine and toluene to hydrogenation reactor A after it has been replaced with hydrogen. After starting the stirrer of hydrogenation reactor A, add a fixed amount of catalyst and hydrogen in sequence. Control the reaction temperature of hydrogenation reactor A to 75-85℃ and the reaction pressure to 3-5MPa. When the reaction pressure of hydrogenation reactor A is stable, it is judged that the reaction is close to completion. After maintaining the pressure for 1 h, depressurize hydrogenation reactor A. The gaseous material enters the tail gas treatment device from the top of hydrogenation reactor A through the first gas phase pipe 1. After depressurization, take a sample for analysis. If the reaction conversion rate is ≥99%, it indicates that the reaction is complete. The mixture after the reaction (amyl ether intermediate of isopropyl methyl chloride and solvent toluene) enters water washing reactor B through the first liquid phase pipe 2.

[0024] (2) Start the agitator of the water washing tank B, add a measured amount of process water and alkali solution in sequence, control the temperature at 10-50℃, stir for 0.5 h, turn off the agitator, and let stand for 2 hours. h. The gaseous material enters the tail gas treatment device from the top of the washing tank B through the second gas phase pipe 3. The liquid material in the washing tank B exhibits stratification. The upper layer is the organic phase (amino ether intermediate of metolachlor and solvent toluene), and the lower layer is the aqueous phase (wastewater). Accurate water separation is achieved through the tuning fork level switch L on the bottom side wall of the washing tank B and the sight glass S on the second liquid phase pipe 4. After the material in the washing tank B has settled, the first three-way valve X is switched to the third liquid phase pipe 5. The aqueous phase (wastewater) enters the wastewater storage tank through the third liquid phase pipe 5. When the tuning fork level switch L issues an alarm signal, observe the sight glass S. If the material color changes from colorless to yellow, switch the first three-way valve X to the fourth liquid phase pipe 6. The organic phase (amino ether intermediate of metolachlor and solvent toluene) enters the distillation tank C through the fourth liquid phase pipe 6.

[0025] (3) Start the stirrer of the distillation vessel C and gradually raise the temperature of the distillation vessel C to 100°C. Switch the No. 2 three-way valve Y to the sixth liquid phase pipe 10. The gaseous substance enters the condenser E through the third gas phase pipe 7. The condensate enters the solvent recovery tank through the sixth liquid phase pipe 10 to obtain the recovered solvent toluene. The gaseous substance that is not condensed in the condenser E enters the tail gas treatment device through the fourth gas phase pipe 9. When the liquid level in the solvent recovery tank no longer changes, gradually raise the temperature of the distillation vessel C to 110°C and switch the No. 2 three-way valve Y to the seventh liquid phase pipe 11. The gaseous substance enters the condenser E through the third gas phase pipe 7, and the condensate enters the intermediate tank V through the seventh liquid phase pipe 11 to obtain the intermediate amine ether of metolachlor (purity ≥97wt%). When the liquid level in the intermediate tank V no longer changes, the temperature of the distillation vessel C is reduced to below 50℃ through the circulating water pipeline of the jacket of the distillation vessel C. The residual liquid in the distillation vessel C enters the residual liquid tank for centralized treatment through the fifth liquid phase pipe 8, and the intermediate amine ether of metolachlor in the intermediate tank V enters the acylation reaction device through the eighth liquid phase pipe 12 for subsequent reaction.

[0026] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to the above embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A system for synthesizing a methyl metolachlor intermediate, comprising a hydrogenation reactor (A), a washing reactor (B), a distillation reactor (C), and a condenser (E), characterized in that: The liquid phase outlet at the bottom of the hydrogenation reactor (A) is connected to the water washing reactor (B) through the first liquid phase pipe (2). The second liquid phase pipe (4) at the bottom of the water washing reactor (B) is connected to the first three-way valve (X). One end of the first three-way valve (X) is connected to the third liquid phase pipe (5), and the other end is connected to the fourth liquid phase pipe (6). The fourth liquid phase pipe (6) is connected to the distillation reactor (C). The gas phase outlet at the top of the distillation reactor (C) is connected to the condenser (E) through the third gas phase pipe (7). The gas phase outlet at the top of the condenser (E) is connected to the tail gas treatment device through the fourth gas phase pipe (9). The liquid phase outlet at the bottom of the condenser (E) is connected to the sixth liquid phase pipe (10) and the seventh liquid phase pipe (11) through the second three-way valve (Y). The sixth liquid phase pipe (10) is connected to the solvent recovery tank, and the seventh liquid phase pipe (11) is connected to the intermediate tank (V). The liquid phase outlet at the bottom of the intermediate tank (V) is connected to the acylation reaction device through the eighth liquid phase pipe (12).

2. The system for synthesizing the intermediate of metolachlor as described in claim 1, characterized in that: The hydrogenation vessel (A), washing vessel (B), and distillation vessel (C) are all equipped with a stirrer for uniformly mixing the materials.

3. The system for synthesizing the intermediate of metolachlor as described in claim 1, characterized in that: The gas phase outlet at the top of the hydrogenation reactor (A) is connected to the tail gas treatment device through the first gas phase pipe (1); the gas phase outlet at the top of the water washing reactor (B) is also connected to the tail gas treatment device through the second gas phase pipe (3).

4. The system for synthesizing the intermediate of metolachlor as described in claim 1, characterized in that: The end of the third liquid phase pipe (5) is connected to the wastewater storage tank; the liquid phase outlet at the bottom of the distillation kettle (C) is connected to the residual liquid tank through the fifth liquid phase pipe (8).

5. A system for synthesizing a methylpropargyl intermediate as described in any one of claims 1-4, characterized in that: The bottom side wall of the washing tank (B) is equipped with a tuning fork level switch (L) to issue an alarm signal when the fork teeth are immersed in the organic phase; the washing tank (B) is connected to the process water inlet pipe and the alkali inlet pipe.

6. The system for synthesizing the intermediate of metolachlor as described in claim 1, characterized in that: The second liquid phase tube (4) is equipped with a sight glass (S) for observing the color of the material.

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