阅读说明：本技术 一种烯草酮的绿色合成方法 (Environment-friendly synthesis method of clethodim ) 是由 李志清 绳敏 李顺仁 贺瑞军 于 2020-08-28 设计创作，主要内容包括：本发明提供了一种烯草酮的绿色合成方法,包括以下步骤：化合物CA与化合物CF在有机酸催化剂的作用下,在蒸馏的条件下进行反应,得到烯草酮；其中,R为甲基,R<Sub>1</Sub>为甲基或乙基。本发明选择催化剂与反应精馏,可以由化合物CA一步制得化合物TM,操作简便,催化剂选择性高,副反应少,反应过程易于控制,整个工艺体系无废盐废水产生。化合物TM收率高,在94％以上,纯度高,在93％以上,容易实行。本发明中的反应条件温和,中间无须酸洗、碱洗、萃取、分层等操作,简化了工艺流程,缩短了反应时间,提高了生产效率,后处理简单,反应完毕即可得到产物,避免了三废、降低了生产成本,符合环保要求,更适合工业化生产。(The invention provides a green synthesis method of clethodim, which comprises the following steps: reacting a compound CA and a compound CF under the action of an organic acid catalyst under the distillation condition to obtain clethodim; wherein R is methyl, R 1 Is methyl or ethyl. The invention selects the catalyst and the reaction rectification, can prepare the compound TM from the compound CA in one step, has simple and convenient operation, high catalyst selectivity, less side reaction, easy control of the reaction process and no waste salt and wastewater generation of the whole process system. The compound TM has high yield of more than 94 percent and high purity of more than 93 percent, and is easy to implement. The method has mild reaction conditions, does not need acid washing, alkali washing, extraction, layering and other operations in the middle, simplifies the process flow, shortens the reaction time, improves the production efficiency, has simple post-treatment, can obtain products after the reaction is finished, and avoids the step IIIWaste, reduces the production cost, meets the requirement of environmental protection, and is more suitable for industrial production.)

1. A green synthesis method of clethodim, comprising the following steps:

reacting a compound CA and a compound CF under the action of an organic acid catalyst under the distillation condition to obtain clethodim;

wherein R is methyl, R₁Is methyl or ethyl.

2. A green synthesis method of clethodim according to claim 1, wherein the catalyst is one or more of formic acid, acetic acid, chloroacetic acid and p-benzoic acid.

3. A green synthesis method of clethodim according to claim 1, wherein the mass of the catalyst is 0.01-50% of the mass of compound CA.

4. A green synthesis process of clethodim according to claim 1, wherein the molar ratio of compound CA to compound CF is 1: (1-5).

5. The green synthesis method of clethodim according to claim 1, wherein the reaction temperature is 10-80 ℃;

the reaction time is 3-10 hours.

6. A green synthesis process of clethodim according to claim 1, wherein the reaction pressure is atmospheric or negative.

7. A green synthesis process of clethodim according to claim 1, wherein said compound CF is prepared by the reaction of a ketoxime with trans-1, 3-dichloropropene in the presence of an alkali metal hydroxide;

the ketoxime is acetone oxime or butanone oxime.

8. A green synthesis method of clethodim according to claim 1, wherein the reaction is carried out by distilling off acetone or butanone produced during the reaction at the reaction temperature.

Technical Field

The invention belongs to the technical field of organic synthesis, and particularly relates to a green synthesis method of clethodim.

Background

The clethodim is chemically named as 2- {1- [ (3-chloro-2-allyl) oxy ] imino propyl } -5- [2- (ethylthio) propyl ] -3-hydroxy-2-cyclohexene-1-ketone, is a broad-spectrum post-emergence herbicide capable of releasing gramineous weeds in broad-leaved crops, has a strong killing effect on annual and perennial gramineous weeds, is mainly suitable for weeding farmlands of more than 40 crops such as soybeans, cotton, peanuts, watermelons and the like, and can also prevent and kill more than 30 gramineous weeds such as barnyard grass and the like.

At present, few reports are made on clethodim synthesis routes, the yield is low, and the wastewater amount is large. In 2001, patent US6300281 reported a specific preparation method of clethodim, comprising the steps of: and carrying out oxime etherification reaction on the compound A and the compound B to obtain clethodim (formula TM). The synthetic route is as follows:

in the actual production process, the CB needs to be excessively promoted to be positively carried out, and after the reaction is finished, the CB also needs to be recovered by hydrochloric acid acidification and liquid alkali neutralization, so that a large amount of sodium chloride wastewater is generated, and the yield is only 81%.

The methods currently used for the synthesis of compound CB are:

wu Yingxiao (pesticides, 2004, 43 (3): 113) introduces a synthetic route: ethyl acetate is acylated to generate N-acetyl hydroxylamine in the presence of sodium hydroxide, then the N-acetyl-O- (3-chloro-2-propenyl) hydroxylamine is prepared by O alkylation with trans-1, 3-dichloropropene under the alkaline condition, then the compound CB is obtained by acidification with hydrochloric acid, neutralization with sodium hydroxide, extraction and desolventization, and a large amount of waste water containing sodium acetate, sodium chloride and ethanol is produced in the process, thereby causing great pollution to the environment.

Therefore, the synthesis process of clethodim has the problems of complicated steps, more waste water, serious pollution and the like, and the yield of clethodim is further improved.

Disclosure of Invention

The invention aims to provide a green synthesis method of clethodim, which avoids the generation of three wastes, simplifies the process flow, shortens the production period, has simple post-treatment, does not need the processes of washing, layering, dehydration and the like, is convenient to separate and purify, is cleaner in the aspect of environmental protection, and has higher yield.

The invention provides a green synthesis method of clethodim, which comprises the following steps:

reacting a compound CA and a compound CF under the action of an organic acid catalyst under the distillation condition to obtain clethodim;

wherein R is methyl, R₁Is methyl or ethyl.

Preferably, the catalyst is one or more of formic acid, acetic acid, chloroacetic acid and p-benzoic acid.

Preferably, the mass of the catalyst is 0.01-50% of that of the compound CA.

Preferably, the molar ratio of the compound CA to the compound CF is 1: (1-5).

Preferably, the reaction temperature is 10-80 ℃;

the reaction time is 3-10 hours.

Preferably, the pressure of the reaction is atmospheric or negative.

Preferably, the compound CF is prepared by reacting ketoxime and trans-1, 3-dichloropropene in the presence of alkali metal hydroxide;

the ketoxime is acetone oxime or butanone oxime.

Preferably, the reaction is carried out while distilling and removing the generated acetone or butanone at the reaction temperature.

The invention provides a green synthesis method of clethodim, which comprises the following steps: reacting a compound CA and a compound CF under the action of an organic acid catalyst under the distillation condition to obtain clethodim; wherein R is methyl, R₁Is methyl or ethyl.

Compared with the prior art, the invention has the following beneficial effects:

1. the invention selects the catalyst and the reaction rectification, can prepare the compound TM from the compound CA in one step, has simple and convenient operation, high catalyst selectivity, less side reaction, easy control of the reaction process and no waste salt and wastewater generation of the whole process system. The compound TM has high yield of more than 94 percent and high purity of more than 93 percent, and is easy to implement.

2. The compound TM is obtained by the reaction of the compound CF, the reaction condition is mild, the operations of acid washing, alkali washing, extraction, layering and the like are not needed in the middle, the process flow is simplified, the reaction time is shortened, the production efficiency is improved, the post-treatment is simple, the product can be obtained after the reaction is finished, the three wastes are avoided, the production cost is reduced, the environmental protection requirement is met, and the method is more suitable for industrial production.

3. The compound TM obtained by the method has high purity and yield and low impurity content.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

FIG. 1 is a LCMS spectrum of the compound prepared in the examples of the present invention.

Detailed Description

The invention provides a green synthesis method of clethodim, which comprises the following steps:

reacting a compound CA and a compound CF under the action of an organic acid catalyst under the distillation condition to obtain clethodim;

wherein R is methyl, R₁Is methyl or ethyl.

The synthetic route of clethodim in the invention is shown as formula I:

in the present invention, the source of the compound CA is not particularly limited, and it may be synthesized by a method known to those skilled in the art.

In the present invention, the compound CF is preferably prepared according to the following steps:

and (2) mixing ketoxime and alkali metal hydroxide with a solvent, heating to 15-50 ℃, dropwise adding trans-1, 3-dichloropropene, and reacting under a stirring condition to obtain the compound CF.

The specific reaction process is shown as formula II:

in the present invention, the ketoxime is preferably acetoxime or butanone oxime, i.e. R is preferably methyl, R1 is preferably methyl or ethyl; the alkali metal hydroxide is preferably sodium hydroxide and/or potassium hydroxide; the solvent is preferably dimethyl sulfoxide.

The mass ratio of the solvent to the ketoxime is preferably (3-20): 1, the molar ratio of the alkali metal hydroxide to the ketoxime is (1.1-1.45): 1; the molar ratio of the trans-1, 3-dichloropropene to the ketoxime is preferably (1.05-1.3): 1.

in the invention, the reaction temperature is preferably 15-50 ℃, and more preferably 20-50 ℃; the reaction time is preferably 1 to 3 hours.

After the reaction is completed, the reaction solution is preferably cooled to room temperature, an extractant is used for extracting the reaction solution for 3-5 times, then the extraction layer is collected and combined, and the extractant in the extraction layer is removed by distillation, so that the compound CF is obtained. The extract is preferably an alkane solvent, more preferably hexane or cyclohexane.

In the present invention, the molar ratio of the compound CA to the compound CF is preferably 1: (1-5), more preferably 1: (1-1.2), most preferably 1: (1-1.3).

The catalyst is preferably organic acid, more preferably one or more of formic acid, acetic acid, chloroacetic acid and p-benzoic acid, and more preferably formic acid; the mass of the catalyst is 0.01-50% of that of the compound CA, more preferably 0.1-10 wt%, and most preferably 0.5-5 wt%.

According to the invention, after a compound CA, a compound CF and a catalyst are mixed according to a mass ratio, the temperature is raised, after the temperature is raised to a reaction temperature, fractions begin to appear, and the generated acetone or butanone is removed by distillation while the reaction is carried out until the reaction is finished, so that clethodim is obtained.

In the present invention, the reaction temperature is preferably 10 to 80 ℃, preferably 20 to 70 ℃, more preferably 50 to 60 ℃, specifically, 56 ℃ in one embodiment of the present invention, 30 ℃ in another embodiment of the present invention, 65 ℃ in another embodiment of the present invention, and 40 ℃ in another embodiment of the present invention. The reaction time is not particularly limited, the reaction can be finished after the reaction of the raw materials is completely determined by measuring the content of the raw materials in the system in the reaction process, and the reaction can be finished after about 5 hours of reaction according to the process in the invention.

In the invention, if the distillation process is performed at normal pressure, the reaction temperature is preferably 50-65 ℃, and specifically, in the embodiment of the invention, the reaction temperature may be 56 ℃ or 65 ℃; if the negative pressure is turned on during the distillation process, the reaction temperature is preferably 20 to 40 ℃, more preferably 30 to 40 ℃, and specifically, in the embodiment of the present invention, 30 ℃ or 40 ℃ may be used.

The invention provides a green synthesis method of clethodim, which comprises the following steps: reacting a compound CA and a compound CF under the action of an organic acid catalyst under the distillation condition to obtain clethodim; wherein R is methyl, R₁Is methyl or ethyl.

Compared with the prior art, the invention has the following beneficial effects:

1. the invention selects the catalyst and the reaction rectification, can prepare the compound TM from the compound CA in one step, has simple and convenient operation, high catalyst selectivity, less side reaction, easy control of the reaction process and no waste salt and wastewater generation of the whole process system. The compound TM has high yield of more than 94 percent and high purity of more than 93 percent, and is easy to implement.

2. The compound TM is obtained by the reaction of the compound CF, the reaction condition is mild, the operations of acid washing, alkali washing, extraction, layering and the like are not needed in the middle, the process flow is simplified, the reaction time is shortened, the production efficiency is improved, the post-treatment is simple, the product can be obtained after the reaction is finished, the three wastes are avoided, the production cost is reduced, the environmental protection requirement is met, and the method is more suitable for industrial production.

3. The compound TM obtained by the method has high purity and yield and low impurity content.

For further illustration of the present invention, the green synthesis of clethodim provided by the present invention is described in detail below with reference to the following examples, which should not be construed as limiting the scope of the present invention.

In the following examples, the compound CA used was synthesized according to the method of patent US 6300281;