CN105418441A - Preparation method for 2,3-dichloro-4-hydroxyaniline - Google Patents
Preparation method for 2,3-dichloro-4-hydroxyaniline Download PDFInfo
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- CN105418441A CN105418441A CN201510973573.7A CN201510973573A CN105418441A CN 105418441 A CN105418441 A CN 105418441A CN 201510973573 A CN201510973573 A CN 201510973573A CN 105418441 A CN105418441 A CN 105418441A
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C213/00—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton
Abstract
The present invention discloses a preparation method for 2,3-dichloro-4-hydroxyaniline. The method comprises the following steps: adding reaction materials 2,3-dichloro-4-phenylazo phenol and a reducing agent to an aqueous solution of sodium hydroxide; reacting at 50-100 DEC C for 2-12 hours; after completion of the reaction, cooling to room temperature; adjusting the pH to 7; then, extracting with ethyl acetate; next, drying over anhydrous sodium sulfate; then, rotationally distilling off the solvent and recrystallizing toluene; and finally, baking to obtain the 2,3-dichloro-4-hydroxyaniline. The reducing agent is selected from one of hydrazine hydrate and sodium hydrosulfite. According to the preparation method disclosed by the present invention, a catalytic reduction method of using hydrogen/metal under a pressurized condition is avoided. It is not required to use expensive and flammable Raney nickel or other metal catalysts, and use any auxiliary. Operations are simple, a yield can be more than 95%, and reaction costs are low, so that the method of the present invention is suitable for large scale industrial production.
Description
Technical field
The invention belongs to the technical field of crop protection agent, be specifically related to the preparation method of the chloro-4-hydroxyanilines of a kind of key intermediate 2,3-bis-.
Background technology
Acid amide fungicides was successfully developed from 1966 and uses, and such crop protection agent has nearly 50 years history as mycocide.Fenhexamid was a kind of novel acid amide fungicides with interior absorption, protectiveness developed by Japanese Beyer Co., Ltd, in official listing in 1999.Fenhexamid and derivatives class mycocide thereof have Crop securify, favourable toxicity data, and good ecological effect, therefore become desirable comprehensive pest and administer medication.
The chloro-4-hydroxyanilines of 2,3-bis-is as the key intermediate of fenhexamid and derivatives class crop bactericide thereof, and its synthetic method has been reported by Japanese Beyer Co., Ltd and protected, and is namely raw material by the arylazo compound replaced, obtains target compound through reduction.The method of preparation process many employings metal catalyzed hydrogenation reduction, hydrogen source is hydrogen or hydrazine hydrate, carries out under the existence of the metals such as Raney's nickel and assistant agent in 0-150 DEG C; Or adopt metal/hydrochloric acid reduction method, metal generally uses iron powder or zinc powder.Above method all needs by metal catalytic, needs on the one hand to use expensive, inflammable Raney's nickel, adds the danger of scale operation; The disagreeableness metal waste residue of a large amount of environment can be produced again on the one hand.
The present inventor has found several new synthetic method in the research of this compounds, and this several novel synthesis not only has mild condition, easy purifying, the advantages such as production cost is low, its operability also improves greatly, effectively reduces reactivity hazard, is applicable to large-scale industrial production.
Summary of the invention
The object of this invention is to provide the preparation method of 2, the 3-bis-chloro-4-hydroxyanilines that a kind of cost is low, risk is low, reaction conditions is gentle.
In order to reach above-mentioned technique effect, the present invention takes following technical scheme:
The preparation method of the chloro-4-hydroxyanilines of a kind of 2,3-bis-, comprises the following steps:
By reaction raw materials 2,3-bis-chloro-4-phenylazo-phenol, reductive agent join in the aqueous solution of sodium hydroxide, react 2 ~ 12 hours at 50 ~ 100 DEG C, after reaction terminates, be cooled to room temperature, regulate pH to 7, then be extracted with ethyl acetate, then use anhydrous sodium sulfate drying, then rotate steaming and desolventize and re crystallization from toluene, finally dry and obtain 2,3-bis-described chloro-4-hydroxyanilines; Described reductive agent is selected from the one in hydrazine hydrate, vat powder.
According to one embodiment of present invention, described reductive agent is hydrazine hydrate, adds ethanol in the aqueous solution of sodium hydroxide.
According to another embodiment of the invention, described reductive agent is hydrazine hydrate, and the mol ratio of 2,3-bis-chloro-4-phenylazo-phenol and hydrazine hydrate is 1:6 ~ 12.
According to another embodiment of the invention, described reductive agent is hydrazine hydrate, and the mol ratio of 2,3-bis-chloro-4-phenylazo-phenol and hydrazine hydrate is 1:4 ~ 12.
According to another embodiment of the invention, described reductive agent is vat powder, and the mol ratio of 2,3-bis-chloro-4-phenylazo-phenol and vat powder is 1:3 ~ 6.
According to another embodiment of the invention, described temperature of reaction is 70 ~ 100 DEG C.
According to another embodiment of the invention, described temperature of reaction is 80 ~ 100 DEG C.
According to another embodiment of the invention, described temperature of reaction is 80 ~ 100 DEG C.
According to another embodiment of the invention, the massfraction of described aqueous sodium hydroxide solution is 40%.
The present invention is described further below.
The chloro-4-hydroxyanilines of in the present invention 2,3-bis-is agricultural chemicals fenhexamid and derivative key intermediates thereof, and its structural formula is as follows:
In the present invention the preparation method of 2,3-bis-chloro-4-hydroxyanilines all with the chloro-4-phenylazo-phenol of arylazo compound 2,3-bis-be raw material preparation, the structural formula of 2,3-bis-chloro-4-phenylazo-phenol is as follows:
The preparation method of the chloro-4-hydroxyanilines of a kind of 2,3-bis-, comprises the following steps:
By reaction raw materials 2,3-bis-chloro-4-phenylazo-phenol, reductive agent join in the aqueous solution of sodium hydroxide, react 2 ~ 12 hours at 50 ~ 100 DEG C, after reaction terminates, be cooled to room temperature, regulate pH to 7, then be extracted with ethyl acetate, then use anhydrous sodium sulfate drying, then rotate steaming and desolventize and re crystallization from toluene, finally dry and obtain 2,3-bis-described chloro-4-hydroxyanilines; Described reductive agent is selected from the one in hydrazine hydrate, vat powder.
The principle of preparation method of the present invention is the electron transport mechanism in chemical reduction.
According to one embodiment of present invention, chloro-for reaction raw materials 2,3-bis-4-phenylazo-phenol, hydrazine hydrate are joined in the aqueous solution of sodium hydroxide, reacts 6 ~ 12 hours at 60 ~ 100 DEG C, after reaction terminates, be cooled to room temperature, regulate pH to 7, be then extracted with ethyl acetate, use anhydrous sodium sulfate drying again, then rotate steaming to desolventize and re crystallization from toluene, finally dry and obtain 2,3-bis-described chloro-4-hydroxybenzenes.
In the above-described embodiment, the mol ratio of 2,3-bis-chloro-4-phenylazo-phenol and hydrazine hydrate is 1:6 ~ 12, if the mol ratio of 2,3-bis-chloro-4-phenylazo-phenol and hydrazine hydrate is less than 1:6, then reduction reaction can not occur; If the mol ratio of 2,3-bis-chloro-4-phenylazo-phenol and hydrazine hydrate is greater than 1:12, then can produces a large amount of by product, be unfavorable for the carrying out of reduction reaction, therefore, the mol ratio of 2,3-bis-chloro-4-phenylazo-phenol and hydrazine hydrate is 1:6 ~ 12 is suitable.According to a preferred embodiment of the invention, 2,3-bis-described chloro-4-phenylazo-phenol and the mol ratio of hydrazine hydrate are 1:8 ~ 10.
In the above-described embodiment, reaction is 60 ~ 100 DEG C, if temperature of reaction is less than 60 DEG C, then reduction reaction can not occur; If temperature of reaction is greater than 100 DEG C, then can produces a large amount of by product, be unfavorable for the carrying out of reduction reaction, therefore temperature of reaction is 60 ~ 100 DEG C is suitable.According to a preferred embodiment of the invention, described temperature of reaction is 80 ~ 100 DEG C.According to preferred embodiment of the present invention, described temperature of reaction is 90 DEG C.
In the above-described embodiment, the mass volume ratio of 2,3-bis-chloro-4-phenylazo-phenol and aqueous sodium hydroxide solution is 1g:3mL ~ 1g:6mL.In the present invention, the effect of sodium hydroxide is the alkalescence regulating reaction system.If do not add aqueous sodium hydroxide solution in this reaction, then reaction can not be carried out, and therefore aqueous sodium hydroxide solution is indispensable in reaction of the present invention.
According to another embodiment of the invention, chloro-for reaction raw materials 2,3-bis-4-phenylazo-phenol, hydrazine hydrate are joined in the mixing solutions of ethanol and aqueous sodium hydroxide solution, reacts 5 ~ 12 hours at 50 ~ 100 DEG C, after reaction terminates, be cooled to room temperature, regulate pH to 7, be then extracted with ethyl acetate, use anhydrous sodium sulfate drying again, then rotate steaming to desolventize and re crystallization from toluene, finally dry and obtain 2,3-bis-described chloro-4-hydroxybenzenes.
In the above-described embodiment, the mol ratio of 2,3-bis-chloro-4-phenylazo-phenol and hydrazine hydrate is 1:4 ~ 12, if the mol ratio of 2,3-bis-chloro-4-phenylazo-phenol and hydrazine hydrate is less than 1:4, then reduction reaction can not be carried out; If the mol ratio of 2,3-bis-chloro-4-phenylazo-phenol and hydrazine hydrate is greater than 1:12, then can produces a large amount of by product, be unfavorable for the carrying out of reduction reaction, therefore, the mol ratio of 2,3-bis-chloro-4-phenylazo-phenol and hydrazine hydrate is 1:4 ~ 12 is suitable.According to a preferred embodiment of the invention, 2,3-bis-described chloro-4-phenylazo-phenol and the mol ratio of hydrazine hydrate are 1:10 ~ 12.
In the above-described embodiment, reaction is 50 ~ 100 DEG C, if temperature of reaction is less than 50 DEG C, then reaction can not be carried out; If temperature of reaction is greater than 100 DEG C, then can produces a large amount of by product, be unfavorable for the carrying out of reduction reaction, therefore temperature of reaction is 50 ~ 100 DEG C is suitable.According to a preferred embodiment of the invention, described temperature of reaction is 70 ~ 100 DEG C.According to the preferred embodiment of the present invention, described temperature of reaction is 80 DEG C.
In the above-described embodiment, the mass volume ratio of 2,3-bis-chloro-4-phenylazo-phenol and aqueous sodium hydroxide solution is 1g:2mL ~ 1g:4mL.In the above-described embodiment, the volume ratio of ethanol and aqueous sodium hydroxide solution is 1:1.In the present invention, the effect of ethanol is the solvability of the chloro-4-phenylazo-phenol of raising 2,3-bis-, and adding a small amount of sodium hydroxide solution can react.
According to another embodiment of the invention, chloro-for reaction raw materials 2,3-bis-4-phenylazo-phenol, vat powder are joined in the aqueous solution of sodium hydroxide, reacts 2 ~ 6 hours at 70 ~ 100 DEG C, after reaction terminates, be cooled to room temperature, regulate pH to 7, be then extracted with ethyl acetate, use anhydrous sodium sulfate drying again, then rotate steaming to desolventize and re crystallization from toluene, finally dry and obtain 2,3-bis-described chloro-4-hydroxybenzenes.
In the above-described embodiment, the mol ratio of 2,3-bis-chloro-4-phenylazo-phenol and vat powder is 1:3 ~ 6, if the mol ratio of 2,3-bis-chloro-4-phenylazo-phenol and vat powder is less than 1:3, then reduction reaction can not occur; If the mol ratio of 2,3-bis-chloro-4-phenylazo-phenol and vat powder is greater than 1:6, then can produces a large amount of by product, be unfavorable for the carrying out of reduction reaction, therefore, the mol ratio of 2,3-bis-chloro-4-phenylazo-phenol and vat powder is 1:3 ~ 6 is suitable.According to a preferred embodiment of the invention, 2,3-bis-described chloro-4-phenylazo-phenol and the mass ratio of vat powder are 1:4 ~ 5.
In the above-described embodiment, reaction is 70 ~ 100 DEG C, if temperature of reaction is less than 70 DEG C, then reduction reaction can not be carried out; If temperature of reaction is greater than 100 DEG C, then can produces a large amount of by product, be unfavorable for the carrying out of reduction reaction, therefore temperature of reaction is 70 ~ 100 DEG C is suitable.According to a preferred embodiment of the invention, described temperature of reaction is 80 ~ 100 DEG C.According to the preferred embodiment of the present invention, described temperature of reaction is 85 DEG C.
In the above-described embodiment, the mass volume ratio of 2,3-bis-chloro-4-phenylazo-phenol and aqueous sodium hydroxide solution is 1g:2mL ~ 1g:4mL.In the present invention, the effect of sodium hydroxide is the alkalescence regulating reaction system.If do not add aqueous sodium hydroxide solution in this reaction, then reaction can not be carried out, and therefore aqueous sodium hydroxide solution is indispensable in reaction of the present invention.
In an embodiment of the present invention, the massfraction of described aqueous sodium hydroxide solution is 40%.If the massfraction of aqueous sodium hydroxide solution is less than 40%, then reaction system hypoalkalinity, can not promote that reduction reaction is carried out; If the massfraction of aqueous sodium hydroxide solution is greater than 40%, then system alkalescence is too strong, causes by product to increase; Therefore, in the present invention, the massfraction of aqueous sodium hydroxide solution is 40% is suitable.
The present invention compared with prior art, has following beneficial effect:
Provided by the present invention 2, the catalytic reduction method of hydrogen/metal is used under the preparation method of the chloro-4-hydroxyanilines of 3-bis-avoids pressurized conditions, do not need to use costliness and inflammable Raney's nickel or other metal catalysts, do not need to use any auxiliary agent, simple to operate, productive rate can reach more than 95%, and reaction cost is low, is applicable to large-scale industrial production.
Accompanying drawing explanation
Fig. 1 is the chloro-4-hydroxyanilines of compound 2,3-bis-
1hNMR characterizes collection of illustrative plates;
Fig. 2 is the chloro-4-hydroxyanilines of compound 2,3-bis-
13cNMR characterizes collection of illustrative plates;
Fig. 3 is that the HPLC-MS of the chloro-4-hydroxyanilines of compound 2,3-bis-characterizes collection of illustrative plates.
Embodiment
Below in conjunction with embodiments of the invention, the invention will be further elaborated.
Embodiment 1:
Hydrazine hydrate/sodium hydroxide solution reduction system prepares the chloro-4-hydroxyanilines of 2,3-bis-
In 100 milliliters of two mouthfuls of flasks that stirrer and reflux condensing tube are housed, add 8.0 grams of (0.03 mole) raw materials 2,3-bis-chloro-4-phenylazo-phenol, is dissolved in the sodium hydroxide solution of 30 milliliter 40%, slowly adds hydrazine hydrate 15.0 grams (0.3 mole).After dropwising, under agitation, 90 DEG C of reactions 10 hours are heated to.After reaction terminates, dilute hydrochloric acid solution is neutralized to pH=7, extraction into ethyl acetate three times, merge organic phase anhydrous sodium sulfate drying, Rotary Evaporators steams and desolventizes, 20 milliliters of re crystallization from toluene, it is 5.08 grams, lightpink crystal that filtration post-drying obtains product, productive rate 95%.
Fig. 1 ~ 3 show the chloro-4-hydroxyanilines of 2,3-bis-
1hNMR sign collection of illustrative plates,
13cNMR characterizes collection of illustrative plates and HPLC-MS characterizes collection of illustrative plates, and the purity that can obtain obtaining in the present embodiment the chloro-4-hydroxyanilines of 2,3-bis-from Fig. 3 is 100%.
Embodiment 2:
Hydrazine hydrate/ethanol, sodium hydroxide solution reduction system prepares the chloro-4-hydroxyanilines of 2,3-bis-
In 100 milliliters of two mouthfuls of flasks that stirrer and reflux condensing tube are housed, add 8.0 grams of (0.03 mole) raw materials 2,3-bis-chloro-4-phenylazo-phenol, be dissolved in the sodium hydroxide mixing solutions of 20 milliliters of ethanol and 20 milliliter 40%, slowly add hydrazine hydrate 19.0 grams (0.36 mole).After dropwising, under agitation, 80 DEG C of reactions 10 hours are heated to.After reaction terminates, dilute hydrochloric acid solution is neutralized to pH=7, extraction into ethyl acetate three times, merge organic phase anhydrous sodium sulfate drying, Rotary Evaporators steams and desolventizes, 20 milliliters of re crystallization from toluene, it is 5.13 grams, lightpink crystal that filtration post-drying obtains product, productive rate 96%.
Embodiment 3:
Vat powder/sodium hydroxide solution reduction system prepares the chloro-4-hydroxyanilines of 2,3-bis-
In 100 milliliters of two mouthfuls of flasks that stirrer and reflux condensing tube are housed, add 8.0 grams of (0.03 mole) raw materials 2,3-bis-chloro-4-phenylazo-phenol, be dissolved in the sodium hydroxide solution of 20 milliliter 40%, 85 DEG C are heated under stirring, a small amount of totally 20 grams, powder (0.12 mole) that in batches takes a policy, and keep temperature to continue reaction 3 hours.After reaction terminates, dilute hydrochloric acid solution is neutralized to pH=7, extraction into ethyl acetate three times, merge organic phase anhydrous sodium sulfate drying, Rotary Evaporators steams and desolventizes, 20 milliliters of re crystallization from toluene, it is 5.28 grams, lightpink crystal that filtration post-drying obtains product, productive rate 98%.
Although with reference to explanatory embodiment of the present invention, invention has been described here, above-described embodiment is only the present invention's preferably embodiment, embodiments of the present invention are not restricted to the described embodiments, should be appreciated that, those skilled in the art can design a lot of other amendment and embodiment, these amendments and embodiment will drop within spirit disclosed in the present application and spirit.
Claims (9)
1. the preparation method of bis-chloro-4-hydroxyanilines, is characterized in that described method comprises the following steps:
By reaction raw materials 2,3-bis-chloro-4-phenylazo-phenol, reductive agent join in the aqueous solution of sodium hydroxide, react 2 ~ 12 hours at 50 ~ 100 DEG C, after reaction terminates, be cooled to room temperature, regulate pH to 7, then be extracted with ethyl acetate, then use anhydrous sodium sulfate drying, then rotate steaming and desolventize and re crystallization from toluene, finally dry and obtain 2,3-bis-described chloro-4-hydroxyanilines; Described reductive agent is selected from the one in hydrazine hydrate, vat powder.
2. the preparation method of 2,3-bis-chloro-4-hydroxyanilines according to claim 1, is characterized in that described reductive agent is hydrazine hydrate, adds ethanol in the aqueous solution of sodium hydroxide.
3. the preparation method of 2,3-bis-chloro-4-hydroxyanilines according to claim 1, is characterized in that described reductive agent is hydrazine hydrate, and the mol ratio of 2,3-bis-chloro-4-phenylazo-phenol and hydrazine hydrate is 1:6 ~ 12.
4. the preparation method of 2,3-bis-chloro-4-hydroxyanilines according to claim 2, is characterized in that described reductive agent is hydrazine hydrate, and the mol ratio of 2,3-bis-chloro-4-phenylazo-phenol and hydrazine hydrate is 1:4 ~ 12.
5. the preparation method of 2,3-bis-chloro-4-hydroxyanilines according to claim 1, is characterized in that described reductive agent is vat powder, and the mol ratio of 2,3-bis-chloro-4-phenylazo-phenol and vat powder is 1:3 ~ 6.
6. the preparation method of 2,3-bis-chloro-4-hydroxyanilines according to claim 2, is characterized in that described temperature of reaction is 70 ~ 100 DEG C.
7. the preparation method of 2,3-bis-chloro-4-hydroxyanilines according to claim 3, is characterized in that described temperature of reaction is 80 ~ 100 DEG C.
8. the preparation method of 2,3-bis-chloro-4-hydroxyanilines according to claim 5, is characterized in that described temperature of reaction is 80 ~ 100 DEG C.
9. the preparation method of 2,3-bis-chloro-4-hydroxyanilines according to claim 1, is characterized in that the massfraction of described aqueous sodium hydroxide solution is 40%.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105732403A (en) * | 2016-03-29 | 2016-07-06 | 中国工程物理研究院化工材料研究所 | Preparation method of 2,3-dichloro-4-hydroxyaniline |
| CN108689875A (en) * | 2018-07-18 | 2018-10-23 | 陕西恒润化学工业有限公司 | A kind of fenhexamid and its synthetic method |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| DE4040853A1 (en) * | 1990-12-20 | 1992-06-25 | Bayer Ag | 2,3-Di:chloro-4-amino-phenol - used as intermediate, for plant protecting agents e.g. fungicides |
| CN1180696A (en) * | 1996-07-08 | 1998-05-06 | 拜尔公司 | Process for preparing 4-hydroxyanilines |
| WO2015057963A1 (en) * | 2013-10-18 | 2015-04-23 | Eisai R&D Management Co., Ltd. | Fgfr4 inhibitors |
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2015
- 2015-12-22 CN CN201510973573.7A patent/CN105418441A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4040853A1 (en) * | 1990-12-20 | 1992-06-25 | Bayer Ag | 2,3-Di:chloro-4-amino-phenol - used as intermediate, for plant protecting agents e.g. fungicides |
| CN1180696A (en) * | 1996-07-08 | 1998-05-06 | 拜尔公司 | Process for preparing 4-hydroxyanilines |
| WO2015057963A1 (en) * | 2013-10-18 | 2015-04-23 | Eisai R&D Management Co., Ltd. | Fgfr4 inhibitors |
Non-Patent Citations (2)
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105732403A (en) * | 2016-03-29 | 2016-07-06 | 中国工程物理研究院化工材料研究所 | Preparation method of 2,3-dichloro-4-hydroxyaniline |
| CN108689875A (en) * | 2018-07-18 | 2018-10-23 | 陕西恒润化学工业有限公司 | A kind of fenhexamid and its synthetic method |
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Application publication date: 20160323 |