阅读说明：本技术 一种由苯醚甲环唑异构体制备3,4′-二氯二苯醚的方法 (Method for preparing 3,4' -dichlorodiphenyl ether from difenoconazole isomer ) 是由 沈浩 吴珊 陈元元 张宝华 刘莹 于 2020-12-28 设计创作，主要内容包括：本发明涉及一种由苯醚甲环唑异构体制备3,4’-二氯二苯醚的方法,该制备方法包括水解、卤仿反应与脱羧反应等步骤。本发明制备方法能够高效地将苯醚甲环唑异构体制成3,4’-二氯二苯醚。该方法不仅可以有效地减少固体废物,变废为宝,降低生产成本,提高经济效益,还可以应用其它药物中间体合成。(The invention relates to a method for preparing 3,4' -dichlorodiphenyl ether from difenoconazole isomer, which comprises the steps of hydrolysis, haloform reaction, decarboxylation reaction and the like. The preparation method can efficiently prepare the difenoconazole isomer into the 3,4' -dichlorodiphenyl ether. The method not only can effectively reduce solid wastes, change wastes into valuables, reduce the production cost and improve the economic benefit, but also can be applied to the synthesis of other drug intermediates.)

1. A method for preparing 3,4' -dichlorodiphenyl ether from difenoconazole isomer is characterized in that the preparation method comprises the following preparation steps:

A. hydrolysis

Subjecting a difenoconazole isomer to the following hydrolytic ring-opening reaction in water in the presence of an acid to give [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone:

B. haloform reaction

In the presence of inorganic base, the [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone obtained in the step A and hypohalite are subjected to the following haloform reaction to obtain 2-chloro-4- (4-chlorophenoxy) -benzoate, and then the 2-chloro-4- (4-chlorophenoxy) -benzoic acid is obtained by acidification:

C. decarboxylation reaction

Subjecting the 2-chloro-4- (4-chlorophenoxy) -benzoic acid obtained in step B to decarboxylation in the presence of copper powder and quinoline to give 3,4' -dichlorodiphenyl ether:

。

2. the preparation method according to claim 1, wherein in the step A, the acid is mixed with the difenoconazole isomer in a molar ratio of 1-20: 1, carrying out hydrolytic ring-opening reaction in water at the temperature of 60-120 ℃ for 1-72 hours.

3. The process according to claim 1 or 2, wherein in step A, the acid is one or more acids selected from the group consisting of hydrochloric acid, sulfuric acid, hydrobromic acid and phosphoric acid.

4. The production method according to claim 1 or 2, characterized in that in step a, the weight ratio of water to the difenoconazole isomer is 1:1.1 to 1.8.

5. The process according to claim 1, wherein in step B, [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazol-4-one obtained in step A, a base and a hypohalite are mixed in a molar ratio of 1: 1-5: 1-10, stirring and reacting for 0.5-24 hours at the temperature of-20-50 ℃.

6. The process according to claim 1 or 5, wherein in the step B, the hypohalite is sodium hypochlorite, potassium hypochlorite, calcium hypochlorite or sodium hypobromite; the alkali is sodium hydroxide, sodium carbonate, potassium hydroxide or potassium carbonate.

7. The process of claim 1 or 5, wherein in step B, the hypohalite is replaced with chlorine and a base solution, or with bromine and a base solution.

8. The method according to claim 1, wherein in the step C, the decarboxylation reaction is performed on the 2-chloro-4- (4-chlorophenoxy) -benzoic acid, the copper powder and the quinoline obtained in the step B at a molar ratio of 1: 0.01-0.2: 2-20 at a temperature of 80-250 ℃ for 1-24 hours.

9. The process of claim 1 wherein [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone prepared in step a has the formula:

。

10. the process of claim 1 wherein 2-chloro-4- (4-chlorophenoxy) -benzoic acid and 2-chloro-4- (4-chlorophenoxy) -benzoic acid salt prepared in step B have the following chemical formula:

and。

[ technical field ] A method for producing a semiconductor device

The invention belongs to the technical field of chemical synthesis. More particularly, the present invention relates to a method for preparing 3,4' -dichlorodiphenyl ether from difenoconazole isomers.

[ background of the invention ]

The difenoconazole, also called difenoconazole, has a trade name of 'shigao', belongs to triazole bactericides, is a sterol demethylation inhibitor, has the characteristics of high efficiency, broad spectrum, low toxicity and low dosage, is an excellent variety of the triazole bactericides, has extremely strong systemic property, can destroy the cell membrane structure and function of pathogenic bacteria by inhibiting the biosynthesis of bacterial cell ergosterol, is used for crops such as fruit trees, vegetables, wheat, potatoes, beans, melons and the like, has good protection and treatment effects on various fungal diseases such as vegetables, melons and fruits and the like, has the characteristics of 'three-in-one' (no environmental pollution, no agricultural product pollution and no natural enemy killing), and is an ideal bactericide for preventing and treating the resistance diseases of crops such as scab, alternaria leaf spot and the like in China and all countries in the world at present.

3,4' -dichlorodiphenyl ether is an important organic synthetic raw material and a medical intermediate, has wide application, can be used for preparing perfumes, particularly soap perfumes and rose mixed perfumes, and can also be used for preparing synthetic resins, organic synthetic raw materials and organic high-temperature heat carriers. The preparation method comprises the steps of adding potassium carbonate and basic copper carbonate as a catalyst into 1, 3-dichlorobenzene and 4-chlorophenol in an N-methyl pyrrolidone solvent, heating to 170-173 ℃, heating for several hours, cooling, filtering, acidifying with hydrochloric acid until the pH value is 6-6.5, then distilling to remove water, distilling under reduced pressure (2kPa), removing residual 1, 3-dichlorobenzene and N-methyl pyrrolidone, and continuing to distill to obtain the product.

About 30% of the product and isomers in the difenoconazole waste liquid cannot be extracted, and only can be treated as hazardous waste or incinerated.

Aiming at the problems in the prior art, the inventor finally completes the invention through a large number of experimental researches and analytical summarization on the basis of summarizing the prior art.

[ summary of the invention ]

[ problem to be solved ]

The invention aims to provide a method for preparing 3,4' -dichlorodiphenyl ether from difenoconazole isomer.

[ solution ]

The invention is realized by the following technical scheme.

The invention relates to a method for preparing 3,4' -dichlorodiphenyl ether from difenoconazole isomer.

The preparation method comprises the following preparation steps:

A. hydrolysis

Subjecting a difenoconazole isomer to the following hydrolytic ring-opening reaction in water in the presence of an acid to give [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone:

B. haloform reaction

In the presence of inorganic base, the [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone obtained in the step A and hypohalite are subjected to the following haloform reaction to obtain 2-chloro-4- (4-chlorophenoxy) -benzoate, and then the 2-chloro-4- (4-chlorophenoxy) -benzoic acid is obtained by acidification:

C. decarboxylation reaction

Subjecting the 2-chloro-4- (4-chlorophenoxy) -benzoic acid obtained in step B to decarboxylation in the presence of copper powder and quinoline to give 3,4' -dichlorodiphenyl ether:

according to a preferred embodiment of the invention, in the step a, the acid is mixed with the difenoconazole isomer in a molar ratio of 1-20: 1, carrying out hydrolytic ring-opening reaction in water at the temperature of 60-120 ℃ for 1-72 hours.

According to another preferred embodiment of the invention, in step a, the acid is one or more acids selected from hydrochloric acid, sulfuric acid, hydrobromic acid or phosphoric acid.

According to another preferred embodiment of the present invention, in step a, the weight ratio of water to the difenoconazole isomer is 1:1.1 to 1.8.

According to another preferred embodiment of the present invention, in step B, [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazol-4-one obtained in step a, a base and a hypohalite are mixed in a molar ratio of 1: 1-5: 1-10, stirring and reacting for 0.5-24 hours at the temperature of-20-50 ℃.

According to another preferred embodiment of the present invention, in step B, the hypohalite is sodium hypochlorite, potassium hypochlorite, calcium hypochlorite or sodium hypobromite; the alkali is sodium hydroxide, sodium carbonate, potassium hydroxide or potassium carbonate.

According to another preferred embodiment of the invention, in step B, the hypohalite is replaced by chlorine and lye or by bromine and lye.

According to another preferred embodiment of the invention, in the step C, the decarboxylation reaction is carried out on the 2-chloro-4- (4-chlorophenoxy) -benzoic acid obtained in the step B, the copper powder and the quinoline according to the molar ratio of 1: 0.01-0.2: 2-20 at the temperature of 80-250 ℃ for 1-24 hours.

The invention also provides [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone prepared in step A, which has the following chemical formula:

and, the present invention also provides 2-chloro-4- (4-chlorophenoxy) -benzoic acid and 2-chloro-4- (4-chlorophenoxy) -benzoic acid salt prepared in step B, which have the following chemical formulas:

and

the present invention will be described in more detail below.

The invention relates to a method for preparing 3,4' -dichlorodiphenyl ether from difenoconazole isomer.

The preparation method comprises the following preparation steps:

A. hydrolysis

Subjecting a difenoconazole isomer to the following hydrolytic ring-opening reaction in water in the presence of an acid to give [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone:

in the step A, the acid and the difenoconazole isomer are mixed according to a molar ratio of 1-20: 1, carrying out hydrolytic ring-opening reaction in water at the temperature of 60-120 ℃ for 1-72 hours.

The acid is one or more acids selected from hydrochloric acid, sulfuric acid, hydrobromic acid or phosphoric acid, all of which are currently marketed products.

In the present invention, if the molar ratio of acid to difenoconazole isomer is less than 1:1, the reaction time is too long, which affects the productivity; if the molar ratio of acid to difenoconazole isomer is higher than 20: 1, the reaction is not obviously influenced and is relatively wasted; therefore, the molar ratio of the acid to the difenoconazole isomer is 1-20: 1 is reasonable; preferably 4 to 15: 1, more preferably 8 to 12: 1.

when the hydrolysis ring-opening reaction time is 1-72 hours, if the temperature of the hydrolysis ring-opening reaction is lower than 60 ℃, the reaction time is too long, and the productivity is influenced; if the temperature of the hydrolytic ring-opening reaction is higher than 120 ℃, impurities are generated; therefore, the temperature of the hydrolytic ring-opening reaction is suitably 60 to 120 ℃, preferably 68 to 110 ℃, more preferably 76 to 98 ℃;

when the temperature of the hydrolysis ring-opening reaction is 60-120 ℃, if the time of the hydrolysis ring-opening reaction is less than 1 hour, the reaction is incomplete; if the time for the hydrolytic ring-opening reaction is longer than 72 hours, time is wasted; therefore, the time of the hydrolytic ring-opening reaction is suitably 1 to 72 hours, preferably 8 to 66 hours, more preferably 12 to 58 hours;

in this step, the weight ratio of water to the difenoconazole isomer is 1:1.1 to 1.8. If the weight ratio exceeds the range, it is not feasible because a certain acid concentration must be ensured. Too much water, too low acid concentration and long reaction time; too little water, high acid concentration, and impurities.

After the hydrolytic ring-opening reaction is finished, the reactants are cooled to room temperature, and a mass spectrometry method is adopted, and the analysis result is shown in the attached figure 1.

As is clear from FIG. 1, the hydrolytic ring-opening reaction gives [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone.

B. Haloform reaction

In the presence of inorganic base, the [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone obtained in the step A and hypohalite are subjected to the following haloform reaction to obtain 2-chloro-4- (4-chlorophenoxy) -benzoate, and then the 2-chloro-4- (4-chlorophenoxy) -benzoic acid is obtained by acidification:

in step B, the [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone obtained in step A, a base and a hypohalite are mixed according to a molar ratio of 1: 1-5: 1-10, stirring and reacting for 0.5-24 hours at the temperature of-20-50 ℃.

The hypohalite is sodium hypochlorite, potassium hypochlorite, calcium hypochlorite or sodium hypobromite; the alkali is sodium hydroxide, sodium carbonate, potassium hydroxide or potassium carbonate. The hypohalites used in the present invention are all products currently on the market.

The hypohalite is replaced by chlorine and alkali liquor, or by bromine and alkali liquor.

The lye is herein described as an aqueous solution of the alkali used in the present invention, the concentration of which is 5 to 40% by weight. When chlorine and alkali liquor are used for replacement, the molar ratio of chlorine to alkali is 1:2, and the dosage (the sum of the two molar numbers) of chlorine and alkali liquor is equal to the molar number of hypohalite; the case of substitution with bromine and alkali solution is the same as that of substitution with chlorine and alkali solution.

In this step, when the amount of [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazol-4-one and hypohalite is within the range, if the amount of the base is less than 1, the reaction is incomplete; if the amount of alkali is higher than 5, it is wasted; therefore, the amount of the base is suitably 1 to 5, preferably 1.6 to 4.5, more preferably 2.2 to 4.0;

when the amount of [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazol-4-one and the base is within the range, if the amount of hypohalite is less than 1, the reaction is incomplete; if the amount of hypohalite is above 10, it is wasted; therefore, the amount of the hypohalite is suitably 1 to 10, preferably 2 to 8, more preferably 3 to 6.0;

in this step, if the temperature of the haloform reaction is below-20 ℃, the reaction can also take place, but energy is wasted; if the temperature of the haloform reaction is higher than 50 ℃, the heat release is large, and the reaction is difficult to control; therefore, the temperature of the haloform reaction is suitably-20 to 50 ℃, preferably-10 to 40 ℃, more preferably-0 to 30 ℃;

under the condition of the temperature of-20 to 50 ℃, if the time of the haloform reaction is shorter than 0.5 hour, the reaction is incomplete; if the time of the haloform reaction is longer than 24 hours, time is wasted; therefore, the time of the haloform reaction is suitably 0.5 to 24 hours, preferably 1.5 to 20 hours, more preferably 3.0 to 16 hours;

after the reaction is finished, the reaction solution is acidified to pH 1-2 by using industrial hydrochloric acid with the concentration of 10-31% by weight at the temperature of-20-50 ℃, then filtered, dried at the temperature of 80-100 ℃ until the water content is lower than 0.1% by weight, and the obtained dried product is subjected to nuclear magnetic hydrogen spectrum analysis as described above, and the analysis result is shown in the attached figure 2.

As is clear from FIG. 2, this hydrolytic ring-opening reaction gives 2-chloro-4- (4-chlorophenoxy) -benzoic acid.

C. Decarboxylation reaction

Subjecting the 2-chloro-4- (4-chlorophenoxy) -benzoic acid obtained in step B to decarboxylation in the presence of copper powder and quinoline to give 3,4' -dichlorodiphenyl ether:

in the step C, the 2-chloro-4- (4-chlorophenoxy) -benzoic acid, the copper powder and the quinoline obtained in the step B are subjected to decarboxylation reaction for 1-24 hours at the temperature of 80-250 ℃ according to the molar ratio of 1: 0.01-0.2: 2-20.

In the present invention, the primary role of the copper powder in this decarboxylation reaction is the catalyst; the main role of quinoline in this decarboxylation reaction is as a solvent.

In this step, when the amount of 2-chloro-4- (4-chlorophenoxy) -benzoic acid and quinoline is within the above range, the reaction is not complete if the amount of copper powder is less than 0.01 part by weight, and is wasted if the amount of copper powder is more than 0.2 part by weight, so that the amount of copper powder is suitably 0.01 to 0.2 part by weight, preferably 0.04 to 0.16 part by weight, more preferably 0.06 to 0.13 part by weight;

when the amount of 2-chloro-4- (4-chlorophenoxy) -benzoic acid and copper powder is within the above range, if the amount of quinoline is less than 2 parts by weight, the solvent is too small and the reaction is difficult to proceed, and if the amount of quinoline is more than 20 parts by weight, it is excessive and wasted, and therefore, it is reasonable to use 2 to 20 parts by weight of quinoline, preferably 4 to 16 parts by weight, more preferably 6 to 12 parts by weight.

The copper powder used in the step is copper powder with the granularity of 100-300 meshes.

The copper powder and quinoline used in the present invention are commercially available products, such as copper powder sold under the name "copper powder" by Shandong Xinyi hong chemical technology Co., Ltd, and quinoline sold under the name "quinoline" by Shandong Hao Shunhai chemical technology Co., Ltd.

In the step, when the reaction temperature is 80-250 ℃, if the decarboxylation reaction temperature is lower than 80 ℃, the reaction does not occur; if the temperature of the decarboxylation reaction is higher than 250 ℃, the by-products generated by the reaction are obviously increased; therefore, the temperature of the decarboxylation reaction is suitably 80 to 250 ℃, preferably 100 to 220 ℃, and more preferably 130 to 190 ℃;

under the condition of the temperature of 80-250 ℃, if the time of the decarboxylation reaction is shorter than 1 hour, the reaction is incomplete; if the decarboxylation reaction time is longer than 24 hours, time is wasted; therefore, the decarboxylation reaction is suitably carried out for 1 to 24 hours, preferably 3 to 20 hours, more preferably 6 to 16 hours;

after the reaction, the reaction solution was mixed with ethyl acetate in a weight ratio of 1: 1-10 ethyl acetate is added for easier filtration, and the obtained filtrate is mixed with hydrochloric acid with the concentration of 10% -20% by weight according to the molar weight of the hydrochloric acid and quinoline of 1-1.5: 1, washing, distilling ethyl acetate out of an ethyl acetate layer at the temperature of 75-78 ℃ under normal pressure, and then carrying out reduced pressure distillation at the temperature of 146 ℃ and the pressure of 5mmHg to obtain the 3,4' -dichlorodiphenyl ether, wherein the specific distillation operation can be referred to CN 101423460A.

The reaction product was subjected to nuclear magnetic hydrogen spectroscopy as described above, and the analysis results are shown in FIG. 3.

The results in FIG. 3 clearly show that the reaction product is 3,4' -dichlorodiphenyl ether.

The yield of the product prepared by the preparation method is calculated according to the following formula:

the weight of the added difenoconazole isomer is a, the weight of the 3,4' -dichlorodiphenyl ether prepared by hydrolysis reaction, haloform reaction and decarboxylation reaction is b, and the product yield is calculated according to the following formula:

(b×283.11)/(239.1×a)×100/％。

[ advantageous effects ]

The invention has the beneficial effects that:

the method for preparing 3,4 '-dichlorodiphenyl ether from the difenoconazole isomer can efficiently prepare the difenoconazole isomer into the 3,4' -dichlorodiphenyl ether. The method not only can effectively reduce solid wastes, change wastes into valuables, reduce the production cost and improve the economic benefit, but also can be applied to the synthesis of other drug intermediates.

[ description of the drawings ]

FIG. 1 is a mass spectrum of a product of a hydrolytic ring-opening reaction of step A of the preparation method of the invention;

FIG. 2 is a nuclear magnetic hydrogen spectrum of a haloform reaction product of step B of the preparation method of the present invention;

FIG. 3 is a nuclear magnetic hydrogen spectrum of a decarboxylation reaction product in step C of the preparation method of the present invention.

[ detailed description ] embodiments

The invention will be better understood from the following examples.

Example 1: preparation of 3,4' -dichlorodiphenyl ether from difenoconazole isomer

The implementation steps of this example are as follows:

A. hydrolysis

In the presence of hydrochloric acid, the ratio by weight of water to difenoconazole isomer (400 g) is 1: 1.2 and at a temperature of 84 ℃, the acid is mixed with the difenoconazole isomer according to a molar ratio of 12: 1, carrying out hydrolytic ring-opening reaction in water for 48 hours, and detecting by a mass spectrometry method described in the specification after the hydrolytic reaction is finished, wherein the product is [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone;

B. haloform reaction

In the presence of sodium hydroxide inorganic base, the [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone obtained in the step A, and the base and sodium hypochlorite according to a molar ratio of 1: 3: 5 stirring at-20 ℃ to carry out a haloform reaction for 24 hours, after the haloform reaction is finished, acidifying reaction liquid by using industrial hydrochloric acid with the concentration of 15% by weight at 0-5 ℃ until the pH value is 1-2, then filtering, drying at 90 ℃ until the water content is below 0.1% by weight, detecting the obtained dried product by using a nuclear magnetic hydrogen spectrometry method described in the specification, wherein the product is 2-chloro-4- (4-chlorophenoxy) -benzoic acid;

C. decarboxylation reaction

In the presence of copper powder and quinoline, the 2-chloro-4- (4-chlorophenoxy) -benzoic acid, the copper powder and the quinoline obtained in the step B are subjected to decarboxylation reaction for 9 hours at the temperature of 155 ℃ according to the molar ratio of 1: 0.08: 8, after the decarboxylation reaction is finished, adding ethyl acetate into the reaction solution according to the weight ratio of the reaction solution to the ethyl acetate of 1: 3 so as to be easier to filter, washing the filtered filtrate by using 15% by weight of hydrochloric acid according to the molar weight of the hydrochloric acid and quinoline of 1.1: 1, evaporating ethyl acetate from an ethyl acetate layer at the temperature of 75-78 ℃ under normal pressure, then, the distillation was carried out under reduced pressure at 146 ℃ and a pressure of 5mmHg to obtain 202 g of a product, which was 3,4' -dichlorodiphenyl ether by the nuclear magnetic hydrogen spectroscopy described in the specification of the present application.

The yield of this example, calculated according to the calculation described in the specification of the application, was 85.8% and the product, analysed by conventional gas chromatography, was 99.1% pure.

Example 2: preparation of 3,4' -dichlorodiphenyl ether from difenoconazole isomer

The implementation steps of this example are as follows:

A. hydrolysis

In the presence of sulfuric acid, the ratio by weight of water to difenoconazole isomer (400 g) is 1: 1.5 and at a temperature of 60 ℃, the acid and the difenoconazole isomer are mixed according to a molar ratio of 1:1, performing hydrolytic ring-opening reaction in water for 15 hours, and detecting by using a mass spectrometry method described in the specification after the hydrolytic reaction is finished, wherein the product is [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone;

B. haloform reaction

In the presence of sodium carbonate inorganic base, the [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone obtained in the step A, the base and sodium hypochlorite hypohalite are mixed according to a molar ratio of 1: 2: 1, stirring at-10 ℃ for carrying out a haloform reaction for 18 hours, after the haloform reaction is finished, acidifying reaction liquid by using industrial hydrochloric acid with the concentration of 15% by weight at 10-25 ℃ until the pH value is 1-2, then filtering, drying at 85 ℃ until the water content is below 0.1% by weight, detecting the obtained dried product by using a nuclear magnetic hydrogen spectrometry method described in the specification, wherein the product is 2-chloro-4- (4-chlorophenoxy) -benzoic acid;

C. decarboxylation reaction

In the presence of copper powder and quinoline, the 2-chloro-4- (4-chlorophenoxy) -benzoic acid, the copper powder and the quinoline obtained in the step B are subjected to decarboxylation reaction for 6 hours at the temperature of 160 ℃ according to the molar ratio of 1: 0.12: 7.5, after the decarboxylation reaction is finished, adding ethyl acetate into the reaction solution according to the weight ratio of the reaction solution to the ethyl acetate of 1:2 so as to be easier to filter, washing the filtered filtrate by using hydrochloric acid with the concentration of 12% by weight according to the molar weight of the hydrochloric acid and quinoline of 1.2: 1, evaporating ethyl acetate from an ethyl acetate layer at the temperature of 75-78 ℃ under normal pressure, then, the distillation was carried out under reduced pressure at 146 ℃ and 5mmHg to obtain 198 g of a product, which was 3,4' -dichlorodiphenyl ether by NMR spectroscopy described in the specification.

The yield of this example was 84% calculated according to the calculation described in the specification of the application, and the product was 99.2% pure by conventional gas chromatography.

Example 3: preparation of 3,4' -dichlorodiphenyl ether from difenoconazole isomer

The implementation steps of this example are as follows:

A. hydrolysis

In the presence of hydrobromic acid at a concentration of 40% by weight, the ratio by weight of water to difenoconazole isomer (400 g) was 1:1.1 and at a temperature of 72 ℃, the acid is mixed with the difenoconazole isomer according to a molar ratio of 4: 1 in water for 32 hours, and after the hydrolysis reaction is finished, the product is [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone detected by a mass spectrometry method described in the specification;

B. haloform reaction

In the presence of potassium hydroxide inorganic base, the [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone obtained in the step A, the base and the potassium hypochlorite according to a molar ratio of 1: 4: 3, stirring at 0 ℃ to carry out a haloform reaction for 12 hours, after the haloform reaction is finished, acidifying reaction liquid by using industrial hydrochloric acid with the concentration of 20% by weight at 5-10 ℃ until the pH value is 1-2, then filtering, drying at 85 ℃ until the water content is below 0.1% by weight, detecting the obtained dried product by using a nuclear magnetic hydrogen spectrometry method described in the specification, wherein the product is 2-chloro-4- (4-chlorophenoxy) -benzoate;

C. decarboxylation reaction

In the presence of copper powder and quinoline, the decarboxylation reaction is carried out on the 2-chloro-4- (4-chlorophenoxy) -benzoic acid, the copper powder and the quinoline obtained in the step B according to the molar ratio of 1: 0.04: 10 at the temperature of 150 ℃ for 8 hours, after the decarboxylation reaction is finished, adding ethyl acetate into the reaction solution according to the weight ratio of the reaction solution to the ethyl acetate of 1: 5 so as to be easier to filter, washing the filtered filtrate by using 10% by weight of hydrochloric acid according to the molar weight of the hydrochloric acid and quinoline of 1.2: 1, evaporating ethyl acetate from an ethyl acetate layer at the temperature of 75-78 ℃ under normal pressure, then, the distillation was carried out under reduced pressure at 146 ℃ and a pressure of 5mmHg to obtain 199 g of a product, which was 3,4' -dichlorodiphenyl ether by the nuclear magnetic hydrogen spectroscopy described in the specification of the present application.

The yield of this example, calculated according to the calculation described in the specification of the application, was 84.5% and the product, analysed by conventional gas chromatography, was 99.3% pure.

Example 4: preparation of 3,4' -dichlorodiphenyl ether from difenoconazole isomer

The implementation steps of this example are as follows:

A. hydrolysis

In the presence of phosphoric acid, the ratio by weight of water to difenoconazole isomer (400 g) is 1: 1.6 and at a temperature of 120 ℃, the acid is mixed with the difenoconazole isomer according to a molar ratio of 16: 1, performing hydrolytic ring-opening reaction in water for 60 hours, and detecting by using a mass spectrometry method described in the specification after the hydrolytic reaction is finished, wherein the product is [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone;

B. haloform reaction

In the presence of potassium carbonate inorganic base, the [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone obtained in the step A, the base and sodium hypochlorite hypohalite are mixed according to a molar ratio of 1: 5: 10 stirring at 15 ℃ to carry out a haloform reaction for 8 hours, after the haloform reaction is finished, acidifying reaction liquid by using industrial hydrochloric acid with the concentration of 15% by weight at 0-10 ℃ until the pH value is 1-2, then filtering, drying at 85 ℃ until the water content is below 0.1% by weight, and detecting by using a nuclear magnetic hydrogen spectrometry method described in the specification, wherein the product is 2-chloro-4- (4-chlorophenoxy) -benzoate;

C. decarboxylation reaction

In the presence of copper powder and quinoline, the 2-chloro-4- (4-chlorophenoxy) -benzoic acid, the copper powder and the quinoline obtained in the step B are subjected to decarboxylation reaction for 5 hours at the temperature of 165 ℃ according to the molar ratio of 1: 0.12: 8, after the decarboxylation reaction is finished, adding ethyl acetate into the reaction solution according to the weight ratio of the reaction solution to the ethyl acetate of 1: 4 so as to be easier to filter, washing the filtered filtrate by using 15% by weight of hydrochloric acid according to the molar weight of the hydrochloric acid and quinoline of 1.1: 1, evaporating ethyl acetate from an ethyl acetate layer at the temperature of 75-78 ℃ under normal pressure, then, the mixture was subjected to distillation under reduced pressure at 146 ℃ and a pressure of 5mmHg to obtain 185 g of a product, which was 3,4' -dichlorodiphenyl ether by NMR spectroscopy as described in the specification.

The yield of this example was 78.6% calculated according to the calculation described in the specification of the application, and the product was 98.9% pure by conventional gas chromatography.

Example 5: preparation of 3,4' -dichlorodiphenyl ether from difenoconazole isomer

The implementation steps of this example are as follows:

A. hydrolysis

In the presence of hydrobromic acid, the ratio by weight of water to difenoconazole isomer (400 g) was 1: 1.3 and at a temperature of 96 ℃, the acid is mixed with the difenoconazole isomer according to a molar ratio of 20: 1, carrying out hydrolytic ring-opening reaction in water for 1 hour, and detecting by a mass spectrometry method described in the specification after the hydrolytic reaction is finished, wherein the product is [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone;

B. haloform reaction

In the presence of cesium carbonate inorganic base, the [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone obtained in the step A, the base and sodium hypobromite hypohalite are mixed according to a molar ratio of 1: 1: 8, stirring at the temperature of 32 ℃ to carry out a haloform reaction for 4 hours, after the haloform reaction is finished, acidifying the reaction liquid by using industrial hydrochloric acid with the concentration of 20% by weight at the temperature of 0-5 ℃ until the pH value is 1-2, then filtering, drying at the temperature of 85 ℃ until the water content is below 0.1% by weight, and obtaining a dried product, wherein the dried product is 2-chloro-4- (4-chlorophenoxy) -benzoic acid detected by adopting a nuclear magnetic hydrogen spectrometry method described in the specification;

C. decarboxylation reaction

In the presence of copper powder and quinoline, the 2-chloro-4- (4-chlorophenoxy) -benzoic acid, the copper powder and the quinoline obtained in the step B are subjected to decarboxylation reaction for 4.5 hours at the temperature of 165 ℃ according to the molar ratio of 1: 0.15: 12, after the decarboxylation reaction is finished, adding ethyl acetate into the reaction solution according to the weight ratio of the reaction solution to the ethyl acetate of 1: 6 so as to be easier to filter, washing the filtered filtrate by using 15% by weight of hydrochloric acid according to the molar weight of the hydrochloric acid and quinoline of 1.5: 1, evaporating ethyl acetate from an ethyl acetate layer at the temperature of 75-78 ℃ under normal pressure, then, the distillation was carried out under reduced pressure at 146 ℃ and a pressure of 5mmHg to obtain 195 g of a product, which was 3,4' -dichlorodiphenyl ether by nuclear magnetic hydrogen spectroscopy described in the specification of the present application.

The yield of this example was 82.8% calculated according to the calculation described in the specification of the application, and the product was 98.8% pure by conventional gas chromatography.

Example 6: preparation of 3,4' -dichlorodiphenyl ether from difenoconazole isomer

The implementation steps of this example are as follows:

A. hydrolysis

In the presence of hydrochloric acid, the ratio by weight of water to difenoconazole isomer (400 g) is 1: 1.8 and at a temperature of 108 ℃, the acid is mixed with the difenoconazole isomer according to a molar ratio of 8: 1, carrying out hydrolytic ring-opening reaction in water for 72 hours, and detecting by a mass spectrometry method described in the specification after the hydrolytic reaction is finished, wherein the product is [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone;

B. haloform reaction

In the presence of sodium carbonate inorganic base, the [ 2-chloro-4- (4-chlorophenoxy) -phenyl ] -2- [1,2,4] triazole-4-ethanone obtained in the step A, the base and sodium hypobromite hypohalite are mixed according to a molar ratio of 1: 3: 6, stirring at 50 ℃ to carry out a haloform reaction for 0.5 hour, after the haloform reaction is finished, acidifying reaction liquid by using industrial hydrochloric acid with the concentration of 20% by weight at 10-20 ℃ until the pH value is 1-2, then filtering, drying at 85 ℃ until the water content is below 0.1% by weight, and obtaining a dried product, wherein the dried product is 2-chloro-4- (4-chlorophenoxy) -benzoate by adopting a nuclear magnetic hydrogen spectrometry method described in the specification;

C. decarboxylation reaction

In the presence of copper powder and quinoline, the 2-chloro-4- (4-chlorophenoxy) -benzoic acid, the copper powder and the quinoline obtained in the step B are subjected to decarboxylation reaction for 3 hours at the temperature of 180 ℃ according to the molar ratio of 1: 0.16: 15, after the decarboxylation reaction is finished, adding ethyl acetate into the reaction solution according to the weight ratio of the reaction solution to the ethyl acetate of 1: 3 so as to be easier to filter, washing the filtered filtrate by using 15% by weight of hydrochloric acid according to the molar weight of the hydrochloric acid and quinoline of 1.3: 1, evaporating ethyl acetate from an ethyl acetate layer at the temperature of 75-78 ℃ under normal pressure, then, the distillation is carried out under reduced pressure at the temperature of 146 ℃ and the pressure of 5mmHg, 190 g of product is obtained, and the product is 3,4' -dichlorodiphenyl ether by the nuclear magnetic hydrogen spectrometry method described in the specification of the application.

The yield of this example was 80.7% calculated according to the calculation described in the specification of the application, and the product was 98.7% pure by conventional gas chromatography.