Process for preparing acetoacetic ester

A technology of acetoacetate and preparation process, which is applied in the preparation of ketene/polyketene, organic chemistry and other directions, can solve the problems such as lower acetoacetate product yield, small production scale, complicated operation and the like, and achieves expansion of production. Ability, easy operation, avoid the effect of reaction deanhydride

Inactive Publication Date: 2011-06-22
SHANGHAI HUAYI GRP CO
View PDF3 Cites 18 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The technical problem to be solved by the present invention is to overcome the small production scale of a single batch batch reaction device in the existing preparation process of acetoacetate, the operation is cumbersome, and it is easy to cause danger due to misoperation, and the acetic anhydride in the reac

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Process for preparing acetoacetic ester

Examples

Experimental program
Comparison scheme
Effect test

Example Embodiment

[0028] Example 1

[0029] Add 32g of methanol and 0.057g of diethylenetriamine as a catalyst to the reaction kettle, dropwise add diketene to react, establish an initial liquid level, add dropwise to the initial reaction solution where the methanol concentration is 5% by mass, and start continuous feeding: methanol 1ml / min , wherein the catalyst content is 0.5%, the refined diketene is 1.5ml / min, the light component circulation flow is 0.8ml / min (wherein, the mass ratio of the circulating material to the discharge is 1:5), and the temperature of the control reactor is controlled at 95 ℃, According to the concentration analysis results, the feed flow is fine-tuned, and the concentration of methanol in the reaction solution is kept at 5% by mass; the discharge flow rate of the reaction kettle is 2.5ml / min, the temperature of the aging flash kettle is controlled at 120 ° C, the operation at normal pressure, and the aging flash The discharge flow rate of the kettle is 2ml / min, and t...

Example Embodiment

[0030] Example 2

[0031] Add 32g of methanol and 0.057g of catalyst triethylenediamine to the reaction kettle, dropwise add diketene to react, establish the initial liquid level, add dropwise to the initial reaction solution, the methanol concentration is 10% by mass, and start the continuous feeding: methanol 1.5ml / min, wherein the catalyst content is 0.1%; the refined diketene is 2ml / min; the circulating flow rate of light components is 0.3ml / min (wherein, the mass ratio of the circulating material to the discharged material is 5:1); the temperature of the control reactor is controlled at 80°C, According to the concentration analysis results, the feed flow rate was fine-tuned, and the concentration of methanol in the reaction solution was kept at 10% by mass; the discharge flow rate of the reaction kettle was 3.5ml / min, the temperature of the aging flash tank was controlled at 105°C, and the operating pressure was 0.9atm (A) , the discharge flow rate of the aging flash ket...

Example Embodiment

[0032] Example 3

[0033] Add 32 g of methanol and 0.057 g of triethylamine as a catalyst to the reaction kettle, drop diketene for reaction, establish an initial liquid level, add dropwise to the initial reaction solution where the methanol concentration is 20% by mass, and start continuous feeding: methanol 1 ml / min, Wherein the catalyst content is 0.35%; the refined diketene is 1.5ml / min; the circulating flow rate of light components is 0.8ml / min (wherein, the mass ratio of the circulating material to the discharged material is 2:5); the temperature of the control reactor is controlled at 60 ° C, according to Concentration analysis results Fine-tune the feed flow rate to keep the methanol concentration in the reaction solution at 20% by mass; the reaction kettle discharge flow rate is 2.5ml / min, the temperature of the aging flash tank is controlled at 130 ° C, the normal pressure operation, the aging flash tank The crude ester liquid was analyzed at a discharge flow rate of...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a process for preparing acetoacetic ester, which comprises the following steps of: continuously feeding diketene and fatty alcohol into a reaction kettle, and performing esterification reaction in the presence of a catalyst; and continuously discharging into an ageing flash tank, distilling out light components and discharging a crude reaction product, wherein the fatty alcohol in the reaction kettle is controlled to be 5 to 20 percent of the total mass of reaction liquid. The preparation process can continuously prepare the acetoacetic ester and improve production capacity, and is easy and convenient to operate, high in safety and low in labor intensity; and the prepared crude acetoacetic ester has high content of target product and hardly contains acetic anhydride impurities which are difficult to remove, and the product quality is ensured.

Description

technical field [0001] The invention belongs to the technical field of chemical industry, and mainly relates to a preparation process of acetoacetate. Background technique [0002] Acetoacetate is an important chemical and pharmaceutical intermediate, which can be used in the synthesis of medicines, pesticides, vitamins and chemical raw materials. At present, relevant patents and literature reports on acetoacetate mainly focus on the improvement of catalysts for the synthesis of acetoacetate. For example, Canadian Patent CA 792793 and U.S. Patent US 2351366 have introduced the use of lower amine trimethylamine or triethylamine as catalysts to catalyze the synthesis of acetoacetate; Chinese patent CN 1280122 has reported ethylene amine catalysts, and CN101337890 has reported Composite catalyst of triethylenediamine and concentrated sulfuric acid. [0003] However, there are few related reports on the preparation process of acetoacetate. In the prior art, the preparation of...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): C07C69/72C07C67/46
Inventor 叶小鹤曾义红王文强陈艳敏蔡兰平石平
Owner SHANGHAI HUAYI GRP CO
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap