An environment-friendly production process of p-aminobenzamide

An aminobenzamide and production process technology, which is applied in the field of environmental protection production process, can solve the problems of large pollution, equipment corrosion, unfavorable environmental protection, etc., and achieve the effect of good reaction selectivity, simple process operation and high operation safety

Active Publication Date: 2019-06-11
XINFA PHARMA
View PDF3 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The price of the acyl chloride reagent used in the above method is relatively high, the acyl chloride reaction releases a large amount of acid gas, the equipment is severely corroded, the amidation reaction of ammonia water produces a large amount of waste water, and the reduction of iron powder produces a large amount of iron sludge. Green industrial production of benzamide

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
  • An environment-friendly production process of p-aminobenzamide
  • An environment-friendly production process of p-aminobenzamide

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] (1) Preparation of ethyl p-nitrobenzoate

[0036] In a 1000 ml four-neck flask connected with stirring, thermometer, water separator, and reflux condenser, 83.5 grams (0.5 moles) of p-nitrobenzoic acid, 250 grams of ethanol, 1.5 grams of p-toluenesulfonic acid, and 120 grams of toluene , 74.4 ° C (toluene-ethanol-water azeotropic) reflux with water for 7 hours, then cooled to 50-60 ° C, low vacuum and reduced pressure recovery ethanol and toluene (for the next batch of reactions), then high vacuum vacuum distillation ( 5-10mmHg) distilled 94.2 grams of ethyl p-nitrobenzoate, yield 96.5%, GC purity 99.9%.

[0037] (2) Preparation of p-aminobenzamide

[0038] In 500 milliliters of stainless steel autoclaves, add 39.0 grams (0.2 moles) ethyl p-nitrobenzoate prepared by step (1), 200 grams of 10% ammonia methanol solution, 0.3 grams of 5% palladium carbon catalyst, after nitrogen replacement three times, Pass in hydrogen, keep the hydrogen pressure at 0.2-0.3 MPa, and rea...

Embodiment 2

[0041] (1) Preparation of ethyl p-nitrobenzoate

[0042] In the 1000 milliliter four-neck flask that is connected with stirring, thermometer, water separator, reflux condenser, 83.5 grams (0.5 moles) p-nitrobenzoic acid, 230 grams of ethanol, 1.5 grams of solid super acid, 120 grams of normal hexane, 56 ℃ (n-hexane-ethanol-water azeotrope) was refluxed with water for 9 hours, then cooled to 40-50°C, low-vacuum and decompressed to recover n-hexane and ethanol (for the next batch of reactions), and then high-vacuum and reduced-pressure distillation ( 5-10mmHg) distilled 95.7 grams of ethyl p-nitrobenzoate, yield 98.2%, GC purity 99.8%.

[0043] (2) Preparation of p-aminobenzamide

[0044]Get 39.0 grams (0.2 moles) of ethyl p-nitrobenzoate prepared in step (1) and join in 500 milliliters of stainless steel autoclave, and add 200 grams of 10% ammonia ethanol solution, 3.5 grams of 50% Raney nickel catalyst, nitrogen displacement After three times, hydrogen gas was introduced to ...

Embodiment 3

[0046] (1) Preparation of ethyl p-nitrobenzoate

[0047] In a 1000 ml four-necked flask connected with stirring, thermometer, water separator, and reflux condenser, 75.0 grams (0.45 moles) of p-nitrobenzoic acid, 250 grams of ethanol, 1.5 grams of p-toluenesulfonic acid, and 150 grams of petroleum Ether, reflux at 65.5°C (petroleum ether-ethanol-water azeotrope) with water to react for 8 hours, then cool to 50-60°C, recover petroleum ether and ethanol (for the next batch reaction) under low vacuum and decompression, and then reduce Pressure distillation (5-10mmHg) distilled 86.5 grams of ethyl p-nitrobenzoate, yield 98.5%, GC purity 99.9%.

[0048] (2) Preparation of p-aminobenzamide

[0049] In 500 milliliters of stainless steel autoclaves, add 39.0 grams (0.2 moles) ethyl p-nitrobenzoate prepared by step (1), 200 grams of 10% ammonia methanol solution, 0.3 grams of 5% palladium carbon catalyst, after nitrogen replacement three times, Pass in hydrogen, keep the hydrogen pre...

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 relates to an environment-friendly production process of p-aminobenzamide, which comprises the following steps: carrying out catalytic esterification reaction on p-nitrobenzoic acid andalcohol to generate p-nitrobenzoate, and carrying out amidation reaction on the p-nitrobenzoate in the presence of a hydrogenation catalyst and hydrogen in an ammonia-alcohol solution to prepare the p-aminobenzamide. The process has the advantages of cheap and easily available raw materials, low wastewater amount, high operation safety, high reaction selectivity, high product yield, high product purity and low cost, and is simple to operate.

Description

technical field [0001] The invention relates to an environment-friendly production process of p-aminobenzamide, which belongs to the technical field of chemistry and chemical engineering. Background technique [0002] P-aminobenzamide is an important intermediate used in the preparation of medicines, dyes, and pigments, in the dyeing of cotton, rayon, and hemp fibers, and in the preparation of inks. It has a wide range of uses. [0003] At present, the preparation of p-aminobenzamide is to prepare p-nitrobenzoyl chloride through acyl chloride reaction (acyl chloride reagent is thionyl chloride or triphosgene) with p-nitrobenzoic acid, and then react with ammonia to generate p-nitrobenzene Formamide, then prepare p-aminobenzamide through iron powder reduction or catalytic hydrogenation reduction (catalyst-hydrazine hydrate method), the total yield is 82.8%, such as CN104193646 and CN106946726, the reaction is described as synthetic route 1 as follows: [0004] [0005] Th...

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): C07C201/12C07C205/57C07C231/02C07C233/65C07C231/12C07C237/30
Inventor 戚聿新鞠立柱王涛
Owner XINFA PHARMA
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