CN114230435B

CN114230435B - Preparation method of octachloronaphthalene

Info

Publication number: CN114230435B
Application number: CN202111618108.3A
Authority: CN
Inventors: 于龙; 张�杰; 周丽娜; 郭钦; 武翰
Original assignee: Shandong Boyuan Pharmaceutical Chemical Co ltd
Current assignee: Shandong Boyuan Pharmaceutical Chemical Co ltd
Priority date: 2021-12-27
Filing date: 2021-12-27
Publication date: 2023-09-12
Anticipated expiration: 2041-12-27
Also published as: CN114230435A

Abstract

The invention discloses a preparation method of octachloronaphthalene, which takes 2-naphthol as a raw material, chlorine is introduced into a solvent for chlorination, nitrogen is introduced after the completion of the chlorination to effectively replace residual chlorine, a chlorinating reagent is added into the system for continuous heating reaction, and after the reaction is finished, cooling and crystallization are carried out, and products are separated through filtration. The preparation method has the advantages of no side reaction, no need of catalyst, rapid reaction, high product content, no need of refining and the like.

Description

Preparation method of octachloronaphthalene

Technical Field

The invention relates to the field of chemical industry, in particular to a preparation method of octachloronaphthalene.

Background

Octachloronaphthalene Octachglonogaphthalene, which is commonly known as "1,2,3,4,5,6,7, 8-Octachloronaphthalene" and is also known as "perchloronaphthalene", with CAS number 2234-13-1, is an octachloro of naphthalene, has good chemical stability and thermal stability, and is used as an insulating material in the electrical industry, an additive for grinding wheel media and cutting oil coolants, and is also used for synthesizing bactericides and algicides. Regarding the preparation of octachloronaphthalene, the synthesis reported in chinese patent CN101844964a is: in an organic solvent, naphthalene is reacted under the action of a metal catalyst at a temperature of between 60 and 130 ℃, chlorine is introduced, the amount of the chlorine is 8.0 to 10.0 times that of the naphthalene, the reaction time is between 6 and 24 hours, and after the reaction, octachloronaphthalene is obtained by post-treatment of reaction liquid; the metal catalyst is iron or zinc; the organic solvent is carbon tetrachloride, tetrachloroethane or tetrachloroethylene. However, the technology has the problems of long reaction time and low yield, and the by-product of the decalin is found to be difficult to control after verification, and the crude product needs to be refined to meet the purity requirement.

Decachloronaphthalene:

decachloro-1,4-dihydronaphthaleneperchloro-1,4-dihydronaphthalenedecachloro-1,4-dihydro-naphthaleneDecachlor-1,4-dihydro-naphthalin1,2,3,4,5,5,6,7,8,8-Decachlor-5,8-dihydro-naphthalinOctachlornaphthalin-1,4-dichlorid

CAS：14396-29-3

disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide the preparation method of the octachloronaphthalene which does not need a catalyst, has the advantages of rapid reaction, no side reaction, high product content and no need of refining.

The invention is realized in the following way: 2-naphthol is taken as a raw material, chlorine is introduced into a solvent for chlorination, nitrogen is introduced after the completion of the chlorination to effectively replace residual chlorine, then a chlorinating reagent is added into the system for continuous heating reaction, after the reaction is finished, the temperature is reduced for crystallization, and products are separated through filtration.

The method specifically comprises the following steps:

(1) Chlorine introducing stage: adding solvent and 2-naphthol into a reaction vessel, heating to the reaction temperature, and then starting to introduce chlorine for reaction;

(2) Hydroxy chlorine band stage: introducing nitrogen into the reaction container after chlorine introduction is completed, effectively replacing residual chlorine, adding a chloro reagent, heating to the reaction temperature for reaction, and tracking by HPLC until the reaction is complete;

(3) Cooling to room temperature after the reaction is finished, and filtering and separating precipitated solid to obtain a product.

The method comprises the following steps of:

(1) Chlorine introducing stage: adding solvent and 2-naphthol into a reaction bottle, connecting ventilation equipment, a stirring device, a condenser tube, a thermometer, a safety bottle and a tail gas absorbing device, and starting ventilation reaction after the temperature of the oil bath is raised to the reaction temperature;

(2) Hydroxy chlorine band stage: and (3) introducing nitrogen into the reaction bottle after the chlorine introduction is completed to effectively replace residual chlorine, adding a chloro reagent, heating to the reaction temperature for reaction, and tracking by HPLC until the reaction is complete.

(3) Cooling to room temperature after the reaction is finished, precipitating a large amount of solids, and filtering and separating to obtain a product. The recrystallization solvent is not needed, the catalyst is not needed, and the by-product of the decalin is not generated.

The solvent in the step (1) is one or more of dichloroethane, carbon tetrachloride, chloroform, tetrachloroethylene, tetrachloroethane and the like; the addition amount of the solvent is 2-15 times of the mass of the naphthol.

The reaction temperature in the step (1) is 60-150 ℃; the reaction time is 4-12h.

The chlorinating agent in the step (2) is one or a mixture of more of phosphorus trichloride, phosphorus pentachloride, phosphorus oxychloride and the like, and the adding amount of the chlorinating agent is 1-3 times of the amount of naphthol substances.

The reaction temperature in the step (2) is 60-150 ℃; HPLC was followed until the reaction was complete, typically for 1-4h.

The excellent effects of the invention are as follows:

(1) No side reaction; in the prior art, naphthalene is taken as a raw material to be introduced with chlorine to prepare octachloronaphthalene, and when octachloronaphthalene products reach a certain amount along with the progress of chlorine introduction reaction, the intermediate which is not chlorinated still exists on naphthalene rings, and the continuous introduction of chlorine can be accompanied with the generation of the ten-chloronaphthalene side reaction of the products which further react with chlorine and cannot be controlled. The key factor of the side reaction is that the product and the intermediate coexist in a large amount, and the new route designed by the invention finally generates heptachloronaphthol in the chlorine introducing process, and no octachloronaphthalene product is generated, so that the occurrence of the side reaction of the decachloronaphthalene is controlled from the source. The heptachloronaphthol is reacted with a chloro reagent to carry out hydroxy chlorohydrin to produce octachloronaphthalene products, and the octachloronaphthalene products are produced in large quantity at the moment, but no chlorine environment exists, so that the decachloronaphthalene side reaction does not occur.

(2) Compared with the prior art, no catalyst is needed, and the cost is low;

(3) The reaction is rapid;

(4) The product has high content and does not need to be refined.

Detailed Description

The advantages of the present invention will now be further described by the following examples, which are to be understood as being for illustrative purposes only and not limiting the scope of the present invention, as obvious variations and modifications thereof by persons skilled in the art are intended to be included within the scope of the present invention.

Example 1

(1) Chlorine introducing stage: 173g of dichloroethane and 57.67g (0.4 mol) of 2-naphthol are added into a reaction bottle, and a ventilation device, a stirring device, a condenser tube, a thermometer, a safety bottle and a tail gas absorbing device are connected, and after the temperature of an oil bath is raised to 85 ℃, 200g (2.8 mol) of ventilation is started for reaction for 8 hours;

(2) Hydroxy chlorine band stage: and (3) introducing nitrogen into the reaction bottle after the chlorine introduction is completed to effectively replace residual chlorine, adding 125g (0.6 mol) of phosphorus pentachloride with the mass which is 1 time that of 2-naphthol, heating to 90 ℃, and tracking by HPLC until the reaction is complete.

(3) After the reaction is finished, the temperature is reduced to room temperature, a large amount of solids are separated out, and 148.56g of product is obtained through filtration and separation.

The yield was 92% and the HPLC content was 99.1%.

Example 2

(1) Chlorine introducing stage: adding 865g of chloroform and 57.67g (0.4 mol) of 2-naphthol into a reaction bottle, connecting a ventilation device, a stirring device, a condenser tube, a thermometer, a safety bottle and a tail gas absorption device, heating an oil bath to 70 ℃, and starting ventilation 285g (4 mol) for reaction for 6 hours;

(2) Hydroxy chlorine band stage: and (3) introducing nitrogen into the reaction bottle after the chlorine introduction is completed to effectively replace residual chlorine, adding 164.8g (1.2 mol) of phosphorus trichloride with the mass which is 3 times that of 2-naphthol, heating to 70 ℃, and tracking by HPLC until the reaction is complete.

(3) After the reaction is finished, the temperature is reduced to room temperature, a large amount of solids are separated out, and 145.33g of product is obtained through filtration and separation.

The yield was 90% and the HPLC content was 99.2%.

Example 3

(1) Chlorine introducing stage: 460g of tetrachloroethylene and 57.67g (0.4 mol) of 2-naphthol are added into a reaction bottle, and ventilation equipment, a stirring device, a condenser tube, a thermometer, a safety bottle and a tail gas absorbing device are connected, and after the temperature of an oil bath is raised to 120 ℃, 227g of ventilation is started for 4 hours;

(2) Hydroxy chlorine band stage: and (3) introducing nitrogen into the reaction bottle after the completion of chlorine introduction to effectively replace residual chlorine, adding 92g (0.6 mol) of phosphorus oxychloride with the mass 1.5 times that of 2-naphthol, heating to 130 ℃, and tracking by HPLC until the reaction is complete.

(3) After the reaction, the temperature is reduced to room temperature, a large amount of solid is separated out, and 153.4g of product is obtained through filtration and separation.

The yield was 95% and the HPLC content was 99%.

Example 4

(1) Chlorine introducing stage: 500g of carbon tetrachloride and 57.67g (0.4 mol) of 2-naphthol are added into a reaction bottle, and a ventilation device, a stirring device, a condenser tube, a thermometer, a safety bottle and a tail gas absorbing device are connected, and after the temperature of an oil bath is raised to 80 ℃, 200g of ventilation is started to react for 12 hours;

(2) Hydroxy chlorine band stage: and (3) introducing nitrogen into the reaction bottle after the chlorine introduction is completed to effectively replace residual chlorine, adding 125g (0.6 mol) of phosphorus pentachloride with the mass 1.5 times of that of 2-naphthol, heating to 90 ℃, and tracking by HPLC until the reaction is complete.

(3) After the reaction is finished, the temperature is reduced to room temperature, a large amount of solids are separated out, and 143.72g of product is obtained through filtration and separation.

The yield was 89% and the HPLC content was 99.4%.

It should be apparent that the above experimental examples are given for clarity of illustration only and are not limiting of the embodiments. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. While still being apparent from variations or modifications that may be made by those skilled in the art are within the scope of the invention.

Claims

1. A method for preparing octachloronaphthalene, comprising the following steps:

(1) Chlorine introducing stage: adding solvent and 2-naphthol into a reaction vessel, heating to the reaction temperature, and then starting to introduce chlorine for reaction; wherein the addition amount of the solvent is 2-15 times of the mass of the 2-naphthol; the chlorine gas is 7-10 times of naphthol substance; the reaction temperature is 60-150 ℃; the reaction time is 4-12h;

(2) Hydroxy chlorination stage: introducing nitrogen into the reaction container after chlorine introduction is completed, effectively replacing residual chlorine, adding a chloro reagent, heating to the reaction temperature for reaction, and tracking by HPLC until the reaction is complete; the reaction temperature is 60-150 ℃; the chloro reagent is one or a mixture of more of phosphorus trichloride, phosphorus pentachloride and phosphorus oxychloride;

2. The method according to claim 1, wherein the solvent in the step (1) is one or more of dichloroethane, carbon tetrachloride, chloroform, tetrachloroethylene, and tetrachloroethane.

3. The process according to claim 1, wherein the chlorinating agent is added in an amount of 1 to 3 times the amount of naphthol material.

4. The method of claim 1, wherein the reaction time in step (2) is 1 to 4 hours.

5. The method of claim 1, wherein the temperature is raised using an oil bath.