Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Low-cost environment-friendly preparation method of 4-methyl-5-alkoxy oxazole

A technology of alkoxyoxazole and alkoxy group, which is applied in the field of environmental protection preparation of 4-methyl-5-alkoxyoxazole, can solve problems such as unfavorable production cost control, waste water generation, and difficulty in obtaining, and achieves the reaction The effect of high atomic efficiency, short process flow and low product cost

Active Publication Date: 2015-05-27
XINFA PHARMA
View PDF4 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The raw material 1,1-dialkoxyacetone used is expensive and difficult to obtain, which is not conducive to production cost control; in addition, after the reaction of 1-alkoxy-1-halogenated acetone and formamide, it is necessary to neutralize the removed hydrogen chloride, which is still There is waste water

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
  • Low-cost environment-friendly preparation method of 4-methyl-5-alkoxy oxazole
  • Low-cost environment-friendly preparation method of 4-methyl-5-alkoxy oxazole

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0047] Embodiment 1: the preparation of 4-methyl-5-methoxy oxazole

[0048] Add 220 grams (1.1 moles) of 27% sodium methylate methanol solution, 500 grams of N,N-dimethylformamide, 75.1 grams (1.0 moles) of nitroethane to the reactor equipped with tail gas absorption device , keep the inner temperature at 50-60°C under stirring, slowly feed 60 grams of carbon dioxide, and stir and react at 60-65°C for 2 hours. Cool to 10°C, add 164.0 grams (1.3 moles) of dimethyl sulfate dropwise, drop it in about 2 hours, stir and react at 10-15°C for 4 hours, then stir and react at 80-85°C for 4 hours (at this time, dimethylamine is released ). Cool to 20°C, filter, wash the filter cake with 30 grams of N,N-dimethylformamide, transfer the filtrate to a 2-liter stainless steel pressure vessel, add 20 grams of wet Pinranil nickel (water content 50%), and replace with nitrogen for 3 The hydrogenation reaction was carried out for 6 hours at 20-25° C. and 2-5 atmospheres of hydrogen. Filter, w...

Embodiment 2

[0049] Embodiment 2: the preparation of 4-methyl-5-methoxy oxazole

[0050] In the reactor, add 59.5 grams (1.1 moles) of solid sodium methylate, 500 grams of tetrahydrofuran, and 75.1 grams (1.0 moles) of nitroethane in sequence, and slowly feed 60 grams of carbon dioxide while stirring to keep the internal temperature between 50-55 ° C. And the reaction was stirred at 60 to 65°C for 2 hours. Cool to 10°C, add 164.5 grams (1.3 moles) of dimethyl sulfate dropwise, drop it in about 2 hours, stir and react at 10 to 15°C for 4 hours, then add 120.0 grams (2.0 moles) of formic acid dropwise at 20-25°C Methyl ester, dripping finished in about 3 hours, thereafter stirred and reacted for 2 hours at 20 to 25°C, filtered, and the filter cake was washed with 30 grams of tetrahydrofuran, and the filtrate was transferred to a 2-liter stainless steel pressure vessel, and 20 grams of wet pinraney nickel (water 50 %), after nitrogen replacement for 3 times, hydrogenation reaction was carrie...

Embodiment 3

[0051] Embodiment 3: the preparation of 4-methyl-5-methoxy oxazole

[0052] Add 59.5 grams (1.1 moles) of solid sodium methylate, 500 grams of tetrahydrofuran (THF), and 75.1 grams (1.0 moles) of nitroethane to the reactor in sequence, and slowly feed 60 grams of carbon dioxide while stirring to keep the internal temperature between 50 and 55°C. And the reaction was stirred at 60 to 65°C for 2 hours. Cool to 20°C, add 144.0 grams (1.6 moles) of dimethyl carbonate dropwise, drop it in about 2 hours, stir and react at 20 to 25°C for 4 hours, then add 120.0 grams (2.0 moles) of formic acid dropwise at 20 to 25°C Methyl ester, dripping finished in about 3 hours, thereafter stirred and reacted for 2 hours at 20 to 25°C, filtered, and the filter cake was washed with 30 grams of tetrahydrofuran, and the filtrate was transferred to a 2-liter stainless steel pressure vessel, and 20 grams of wet pinraney nickel (water 50 %), after nitrogen replacement for 3 times, hydrogenation reactio...

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 a low-cost environment-friendly preparation method of 4-methyl-5-alkoxy oxazole. The method comprises the following steps: introducing carbon dioxide into a mixture of nitroethane, alkaline reagent and solvent, carrying out alkylation reaction and formylation reaction to generate 1-alkoxy-1-formyloxy-2-nitropropylene, and directly carrying out catalytic hydrogenation cyclization reaction without separation to obtain the 4-methyl-5-alkoxy oxazole. The method has the advantages of cheap and accessible raw materials, simple reaction operation, low product cost, no discharge of waste liquid or wastewater, high safety and environment friendliness.

Description

technical field [0001] The invention relates to an environmentally friendly preparation method of low-cost 4-methyl-5-alkoxy oxazole, which belongs to vitamin B 6 Technical field of chemical synthesis of intermediates. Background technique [0002] Vitamin B present 6 (referred to as VB 6 ) industrially synthesized is generally pyridoxine hydrochloride, the prior art mostly adopts the oxazole method to synthesize, and 4-methyl-5-alkoxy oxazole is the synthesis of vitamin B by the oxazole method 6 important intermediates. The preparation method of 4-methyl-5-alkoxy oxazole mainly contains two kinds at present: [0003] 1. Prepare ethyl N-formyl-2-aminopropionate through formylation with ethyl 2-aminopropionate, and form a ring with phosphorus pentoxide or other dehydrating agents. However, this method consumes a large amount of phosphorus pentoxide for ring formation, has a large amount of waste water, and has low yield and high cost, which is not conducive to industrial...

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): C07D263/42
CPCC07D263/42
Inventor 戚聿新吕强三鞠立柱李新发
Owner XINFA PHARMA
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com