Preparation method of ethyl p-aminobenzoate

A technology of ethyl aminobenzoate and p-nitrobenzoic acid, which is applied in the field of preparation of ethyl aminobenzoate, can solve the problems of unsuitable publicity and opening of student experiments, high raw material prices, and difficult separation, and achieve high cost performance and high product quality. Good quality, short time effect

Active Publication Date: 2020-10-02
浙江优创材料科技股份有限公司
View PDF8 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In the above-mentioned method, method (1) step is loaded down with trivial details, and raw material price is high, is unsuitable to publicize and set up student's experiment; salt, not easy to separate

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
  • Preparation method of ethyl p-aminobenzoate
  • Preparation method of ethyl p-aminobenzoate
  • Preparation method of ethyl p-aminobenzoate

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0033] A preparation method of ethyl p-aminobenzoate, comprising the steps of:

[0034] (1) p-Nitrobenzoic acid, ethanol, composite catalyst are dropped in the reactor;

[0035] (2) Reaction for 7 hours under reflux conditions to obtain ethyl p-aminobenzoate, intermediate p-aminobenzoic acid, and unreacted complete p-nitrobenzoic acid;

[0036] (3) The catalyst was filtered out, and the filtered catalyst was washed with ethanol at 50° C. and used for the next batch of reactions. ;

[0037] (4) excess ethanol is removed from the reaction solution, and the residue is dissolved in toluene to obtain a toluene reaction solution;

[0038] (5) the toluene reaction solution is washed with alkali and washed with water, and left to stand for stratification to obtain a toluene layer and an alkaline water layer;

[0039] (6) the toluene layer obtains ethyl p-aminobenzoate through cooling, crystallization, and centrifugation, and obtains the finished product of ethyl p-aminobenzoate aft...

Embodiment 2-6

[0047] Embodiment 2-6 (following embodiment is used for researching the impact of composite catalyst on product)

[0048] Others are all the same as in Example 1, except that the composite catalyst is different, and the details are as follows:

[0049] The influence of table 1 composite catalyst on product

[0050]

Embodiment 7-11

[0051] Embodiment 7-11 (following embodiment is used for researching the impact of composite catalyst preparation method on product)

[0052] Others are all the same as in Example 1, except that the preparation method of the composite catalyst is different, and the details are as follows:

[0053] Table 1 The impact of the composite catalyst preparation method on the product

[0054]

[0055]

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

PropertyMeasurementUnit
melting pointaaaaaaaaaa
Login to view more

Abstract

The invention relates to the technical field of fine chemical engineering, in particular to a preparation method of ethyl p-aminobenzoate. The invention relates to a preparation method of ethyl p-aminobenzoate, which is characterized by comprising the following steps: (1) adding p-nitrobenzoic acid, ethanol and a composite catalyst into a reaction kettle; (2) carrying out a reaction for 6-8 h under a reflux condition to obtain ethyl p-aminobenzoate, an intermediate p-aminobenzoic acid and p-nitrobenzoic acid which is not completely reacted; and (3) carrying out post-treatment to obtain the ethyl p-aminobenzoate finished product. The composite catalyst is composed of sulfate, an inorganic reducing agent, a diatomite and an amine accelerator.

Description

technical field [0001] The invention relates to the technical field of fine chemicals, in particular to a preparation method of ethyl p-aminobenzoate. Background technique [0002] Ethyl p-aminobenzoate is also known as benzocaine (ABEE). Colorless orthorhombic crystal, odorless and tasteless. Molecular weight 165.19. The melting point is 91-92°C. Soluble in alcohol, ether, chloroform. Soluble in almond oil, olive oil, dilute acid. Insoluble in water. It is clinically used for pain relief and antipruritic of wounds, ulcers, burns, skin abrasions and hemorrhoids. [0003] The synthetic route of benzocaine can be summarized as following 2 kinds: (1) take p-toluene gum as raw material, make benzocaine through acylation, oxidation, hydrolysis, esterification; Iron reduces p-nitrobenzoic acid to obtain p-aminobenzoic acid, and then esterifies with absolute ethanol under acidic conditions to obtain benzocaine. In the above-mentioned method, method (1) step is loaded down w...

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
Patent Type & Authority Applications(China)
IPC IPC(8): C07C229/60C07C227/04B01J31/26
CPCB01J31/26C07C227/04C07C2531/26C07C229/60
Inventor 茅月成吴建龙施根祥
Owner 浙江优创材料科技股份有限公司
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