Method for preparing 2-trifluoro methyl benzoxazole

A technology of trifluoromethylbenzoxazole and triphenylphosphine, which is applied in the field of preparation of 2-trifluoromethylbenzoxazole, can solve the problems of 2-trifluoromethylbenzoxazole, This type of compound has less research and other problems, and achieves the effect of high yield and simple operation

Inactive Publication Date: 2006-05-24
SHANGHAI UNIV
View PDF0 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0008] It can be seen that there are not many methods for preparing 2-trif

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
  • Method for preparing 2-trifluoro methyl benzoxazole
  • Method for preparing 2-trifluoro methyl benzoxazole

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0015] Example one: under nitrogen protection, add triphenylphosphine (34.5 grams, 132 mmoles), triethylamine (18.2 milliliters, 132 millimoles), carbon tetrachloride (21.1 milliliters, 220 milliliters) in the two-necked flask of 250 milliliters millimoles), and a reflux condenser was installed. Cool to 0°C with an ice-water bath while stirring, add trifluoroacetic acid (3.4 ml, 44 mmol) with a syringe through the reversing plug, stir at 0°C for ten minutes, add o-aminophenol (5.8 g, 53 mmol) and carbon tetrachloride solution (21.1 mL, 220 mmol). Slowly heat to 60°C (oil bath temperature), the triphenylphosphine is completely dissolved, and the mixed solution will be relatively clear at this time. Maintain this temperature for a period of time (about 15 minutes), and it can be observed that once the reaction is initiated, the reaction will become very intense, a large amount of heat will be released, violent reflux, and a large amount of white solid will be produced, which is...

example 2

[0016] Example two: under nitrogen protection, add triphenylphosphine (261.37 grams, 1 mole), triethylamine (137.9 milliliters, 1 mole), carbon tetrachloride (159.8 milliliters, 1.67 moles) in a 1-liter two-necked flask , install the reflux condenser. Cool to 0°C with an ice-water bath under stirring, add trifluoroacetic acid (25.76 ml, 0.333 mol) with a syringe through the reversing plug, stir at 0°C for fifteen minutes, add o-aminophenol (44.0 g, 0.402 mol) and Carbon tetrachloride solution (159.8 mL, 1.67 mol). Slowly heat to 60°C (oil bath temperature), the triphenylphosphine is completely dissolved, and the mixed solution will be relatively clear at this time. Maintain this temperature for a period of time (about 20 minutes), and it can be observed that once the reaction is initiated, the reaction will become very intense, a large amount of heat will be emitted, violent reflux, and a large amount of white solid will be produced, which is a salt of triethylamine salt and...

example 3

[0017] Example three: under nitrogen protection, add triphenylphosphine (2.614 kilograms, 10 moles), triethylamine (1.379 liters, 10 moles), carbon tetrachloride (1.598 liters, 16.7 moles) in 10 liters of two-necked flasks , install the reflux condenser. Cool to 0°C with an ice-water bath under stirring, add trifluoroacetic acid (257.6 ml, 3.333 mol) with a syringe through the reversing plug, stir at 0°C for 20 minutes, add o-aminophenol (0.44 kg, 4.015 mol) and Carbon tetrachloride solution (1.598 L, 16.7 moles). Slowly heat to 60°C (oil bath temperature), the triphenylphosphine is completely dissolved, and the mixed solution will be relatively clear at this time. Maintain this temperature for a period of time (about 25 minutes), and it can be observed that once the reaction is initiated, the reaction will become very intense, a large amount of heat will be released, violent reflux, and a large amount of white solid will be produced, which is a salt of triethylamine salt an...

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 method for preparing 2-trifluoromethylbenzo oxazole, including the steps of as follows: under the protection of nitrogen gas, using carbon tetrachloride as solvent, adding triphenyl phosphine and triethylamine in the reacting container, blending and lowering the temperature to 0 deg.C under the ice water bathing; then adding in trifluoro acetic acid, blending 10-20 minutes, finally adding in carbon tetrachloride dissolved ortho-aminophenol, where the molar ratio of four reactants triphenyl phosphine, triethylamine, trifluoro acetic acid, and ortho-aminophenol is (3-3.5) : (3-3.5) : 1 : (1-1.2); heating to start acute reaction, immediately removing heat source, continuing returning and reacting 3-5 hours, as the reaction ends, vacuum evaporating the solvent from the reacting solution, then adding the solvent petroleum mixed of petroleum ether and acetate in the bulk ratio of 10 to 1 into a bottle to mix into a, soaking, pump filtering, washing the solid in buchner funnel with the mixed solution; making chromatographic resolution on the obtained liquor, and collecting the 25-28 deg.C/2mmHg fractions, thus obtaining the products 2-trifluoromethylbenzo oxazole. The material materials of the invention are easy to obtain, the operation is extremely simple, and the synthesis is one-boiler made. The method has high yield, suitable to large-scale production.

Description

technical field [0001] The invention relates to a preparation method of 2-trifluoromethylbenzoxazole. Background technique [0002] Heterocyclic compounds are widely distributed in nature, accounting for almost one-third of the known organic compounds, and have many uses. Many important substances, such as chlorophyll, heme, nucleic acid, and some natural and synthetic drugs with significant curative effects in clinical applications, all contain the structure of heterocyclic compounds. Alkaloids are mostly active ingredients of Chinese herbal medicines, most of which are nitrogen-containing heterocyclic compounds. [0003] The benzoxazole ring system has certain medicinal properties and exists in a few drugs. In addition, it is also an important intermediate of dyes, pesticides, and medicines. Such organic compounds are widely used in the preparation of medicines, dyes, and pesticides. At present, there is a fluorescent brightening agent OB that contains two benzoxazole s...

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): C07D263/56
Inventor 郝健葛凤莲刘义平
Owner SHANGHAI UNIV
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