阅读说明：本技术 一种双季铵盐中间体的制备方法 (Preparation method of biquaternary ammonium salt intermediate ) 是由 程终发 殷昂 周响 申义驰 于 2020-07-13 设计创作，主要内容包括：本发明提供了一种双季铵盐中间体的制备工艺,用1,3-二氯丙醇与长碳链二甲胺在丙酮中反应生成一种双季铵盐中间体。本发明采用1,3-二氯丙醇做连接基,依托于1,3-二氯丙醇生产线,扩展了1,3-二氯丙醇的产业链及应用；本发明生产的双季铵盐中间体纯度高,易分离；本发明实现连续化生产,有利于工业推广。(The invention provides a preparation process of a biquaternary ammonium salt intermediate, which comprises the step of reacting 1, 3-dichloropropanol with long-carbon-chain dimethylamine in acetone to generate the biquaternary ammonium salt intermediate. The invention adopts 1, 3-dichloropropanol as a linking group, relies on a 1, 3-dichloropropanol production line, and expands the industrial chain and application of the 1, 3-dichloropropanol; the biquaternary ammonium salt intermediate produced by the invention has high purity and is easy to separate; the invention realizes continuous production and is beneficial to industrial popularization.)

1. The preparation method of the biquaternary ammonium salt intermediate is characterized by comprising the following steps:

(1) adding 1, 3-dichloropropanol into a reaction kettle, starting stirring, dropwise adding an acetone solution of amine, and continuously heating the reaction kettle to the reaction temperature in the feeding process;

(2) continuously feeding materials, keeping the reaction temperature while stirring, separating and enriching solid intermediate products at the bottom of the kettle, collecting and separating mixed liquor rich in the intermediate at the bottom of the kettle to obtain mother liquor and a crude product of the solid biquaternary ammonium salt intermediate;

(3) purifying to obtain the biquaternary ammonium salt intermediate 3-chlorine-2-hydroxypropyl R alkyl dimethyl ammonium chloride.

2. The method of claim 1, wherein the total amount of acetone is 1/4-1/3 of the total volume of the reaction kettle, and the amine is alkyl dimethyl tertiary amine containing alkyl carbon chain 10-20.

3. The method of claim 1, wherein the amine is octaalkyldimethyl tertiary amine, decaalkyldimethyl tertiary amine, dodecyl dimethyl tertiary amine, or tetradecyldimethyl tertiary amine.

4. The method of claim 1, wherein the molar ratio of 1, 3-dichloropropanol to amine is 1.5-2: 1, and the total volume of the two is 1/10-1/6 of the total volume of the reaction kettle.

5. The method according to claim 1, wherein the dropwise addition of the acetone solution of the amine is carried out for 1 to 3 hours; the reaction temperature is 80-90 ℃.

6. The method according to claim 1, characterized in that the purification is in particular: and (3) carrying out vacuum drying on the crude product of the biquaternary ammonium salt intermediate under the pressure of-0.1 MPa, separating an organic matter from the biquaternary ammonium salt intermediate 3-chloro-2-hydroxypropyl R alkyl dimethyl ammonium chloride, and pumping the mother liquor and the organic matter into a reaction kettle for recycling so as to realize continuous production.

Technical Field

The invention relates to the technical field of fine chemicals, in particular to a synthetic method of a biquaternary ammonium salt intermediate.

Background

In recent years, the biquaternary ammonium salt surfactant has attracted much attention due to its low toxicity, wide biological activity, good water solubility and other features. The asymmetric biquaternary ammonium salt has asymmetry, high surface activity and unique physicochemical property, is widely applied to the fields of bactericide, novel molecular sieve synthesis and the like, and has excellent performance.

At present, the synthesis research of the asymmetric biquaternary ammonium salt has obtained certain achievements, and the asymmetric biquaternary ammonium salt is mainly synthesized by reacting epichlorohydrin or short-chain dihalogenated alkyl serving as a connecting group with dimethyl tertiary amine with different models. For example, in the remainder science, epichlorohydrin and dimethyl tertiary amine are used for generating an intermediate, and then the intermediate reacts with long-chain oleic acid imidazoline to generate asymmetric biquaternary ammonium salt; under the condition of isopropanol, 1, 2-dibromoethane and dimethyl tertiary amine are used by the Wangcheng et al to synthesize a C10-C2-C12 type asymmetric biquaternary ammonium salt surfactant (Zhengzhou university, 2010). In addition, researchers have also shown other synthetic routes. For example, patent CN104211620B uses disulfonate to react with tertiary amine to generate asymmetric biquaternary ammonium salt; in patent CN106674017B, long-chain alkyl halide and medium-chain di-tertiary amine are reacted to generate an intermediate, and then the intermediate is reacted with short-chain alkyl halide to generate asymmetric biquaternary ammonium salt.

To synthesize high-content asymmetric biquaternary ammonium salt, the conversion degree of the intermediate must be controlled, and the continuous reaction to generate the symmetric biquaternary ammonium salt is avoided while ensuring the generation of a large amount of the intermediate. Due to different reactive groups, the epichlorohydrin can well control the generation of intermediates, but has great harm to human health, active chemical properties and easy fire and explosion. In terms of production safety and occupational health, a safer and healthier linking group is selected for reaction. The company has formed a production chain line of 1, 3-dichloropropanol with a certain scale, provides a production method for synthesizing a biquaternary ammonium salt intermediate by using 1, 3-dichloropropanol as a connecting group, provides a relatively safe and healthy production environment, and widens downstream products and application of the 1, 3-dichloropropanol.

Disclosure of Invention

Aiming at the problems of low conversion rate and complex reaction of quaternary ammonium salt intermediates in the prior art, the invention provides a preparation method of a biquaternary ammonium salt intermediate.

A preparation process of a biquaternary ammonium salt intermediate mainly comprises the following steps:

(1) adding a certain amount of acetone into a reaction kettle, starting stirring, heating to 50 ℃, then respectively pumping 1, 3-dichloropropanol and R alkyl dimethylamine according to a certain flow, continuously heating up in the reaction kettle in the feeding process, and after dropwise adding for about 1h, heating the temperature in the reaction kettle to 80 ℃.

(2) Continuously feeding materials, keeping the temperature in the reaction kettle at 80-90 ℃ under stirring, separating and enriching solid intermediate products at the bottom of the kettle, collecting and separating the mixed liquid rich in the intermediate at the bottom of the kettle to obtain mother liquor and a crude product of the solid biquaternary ammonium salt intermediate.

(3) Vacuum drying the crude product of the biquaternary ammonium salt intermediate under the pressure of-0.1 MPa, separating organic matters from the 3-chloro-2-hydroxypropyl R alkyl dimethyl ammonium chloride of the biquaternary ammonium salt intermediate, and pumping the mother liquor and the organic matters into a reaction kettle for recycling to realize continuous production

Wherein the addition amount of the acetone in the step (1) is 1/4-1/3 of the total volume in the reaction kettle, and R of the R alkyl dimethylamine is eight, ten, twelve and fourteen.

Wherein the flow molar ratio of the pumped 1, 3-dichloropropanol to the R alkyl dimethylamine in the step (1) is (1.5-2): 1, the total flow of the pumped 1, 3-dichloropropanol and the R alkyl dimethylamine is (1/10-1/6) accounting for the total volume of the reaction kettle per hour, and the specific flow is determined by the total volume of the reaction kettle.

According to the invention, 1, 3-dichloropropanol is used as a connector of the biquaternary ammonium salt, other auxiliary agents are not needed in the reaction process, and the acetone solution of amine is injected in a dropwise manner, 1, 3-dichloropropanol is used as a reaction solvent and a reaction raw material, and the excessive amount of 1, 3-dichloropropanol is ensured by dropwise adding, so that the yield of the quaternary ammonium salt intermediate is ensured, the accumulated acetone is dropwise added as the reaction solvent in the final reaction stage, the liquid amount in the reaction kettle is ensured, and the production safety is ensured.

The invention has the beneficial effects

According to the invention, 1, 3-dichloropropanol is used as a connector of the biquaternary ammonium salt, no additional additive is needed in the reaction process, the reaction temperature is low, the reaction speed is high, and the yield of the biquaternary ammonium salt intermediate is high.

Detailed Description

The present invention is described in detail below by way of examples, which are intended to be illustrative only and not to be construed as limiting the scope of the invention, and one skilled in the art will be able to make variations within the scope of the invention based on the disclosure herein, in reagents, catalysts and reaction process conditions. All equivalent changes or modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.