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Chemical synthesis method of 3-(2-chlorophenyl)-5-methyl-4-isoxazole formyl chloride

An isoxazolecarbonyl and chemical synthesis technology, which is applied in the field of chemical synthesis of 3-2-chlorophenyl)-5-methyl-4-isoxazolecarbonyl chloride, can solve the problem of poor production safety and serious equipment corrosion , long reaction cycle and other problems, to achieve the effect of low production cost, small equipment corrosion, safe and reliable production

Inactive Publication Date: 2004-10-13
ZHEJIANG UNIV OF TECH
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The disadvantage of this process is that it uses the relatively toxic raw materials such as thionyl chloride or phosphorus oxychloride or phosphorus pentachloride or phosphorus trichloride, which are internationally controlled. The production safety is poor, and the reaction cycle is long, and the equipment is seriously corroded, which is the most troublesome. What is more, the amount of three wastes is large, and the treatment is difficult and expensive

Method used

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  • Chemical synthesis method of 3-(2-chlorophenyl)-5-methyl-4-isoxazole formyl chloride

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0012] 3-(2-chlorophenyl)-5-methyl-4-isoxazolecarboxylic acid: bis(trichloromethyl) carbonate: tetrabutylurea=1: 0.33: 0.02 (molar ratio), the toluene consumption is 10 times the mass of 3-(2-chlorophenyl)-5-methyl-4-isoxazolecarboxylic acid.

[0013] 3-(2-Chlorophenyl)-5-methyl-4-isoxazolecarboxylic acid, tetrabutylurea and toluene were added to the reaction kettle, after stirring evenly, bis(trichloro Toluene solution of methyl)carbonate, open the hydrogen chloride absorption system at the same time, then raise the temperature to 110°C, reflux for 2 hours, and recover the toluene by distillation under reduced pressure after the reaction, and finally collect the distillate at 130-132°C at 0.667KPa, freeze solidify. The yield is 95.6%, the melting point is 42-43°C, and the content (HPLC) is 99.6%.

Embodiment 2

[0015] 3-(2-chlorophenyl)-5-methyl-4-isoxazolecarboxylic acid:bis(trichloromethyl)carbonate:tetrabutylurea=1:0.5:0.01 (molar ratio), o-dichloro The amount of benzene used is 5 times the mass of 3-(2-chlorophenyl)-5-methyl-4-isoxazolecarboxylic acid.

[0016] Add 3-(2-chlorophenyl)-5-methyl-4-isoxazolecarboxylic acid, tetrabutylurea and o-dichlorobenzene into the reaction kettle, stir evenly, add bis (Trichloromethyl) carbonate tetrahydrofuran solution, open the hydrogen chloride absorption system at the same time, then raise the temperature to 145-150 ° C for 1 hour, after the reaction is complete, first recover o-dichlorobenzene by vacuum distillation, then vacuum distillation, at 0.667KPa The fractions at 130-132°C were collected, frozen and solidified, the yield was 96.0%, the melting point was 41-42°C, and the content (HPLC) was 99.2%.

Embodiment 3

[0018] 3-(2-chlorophenyl)-5-methyl-4-isoxazolecarboxylic acid: bis(trichloromethyl)carbonate: tetrabutylurea=1:0.50:0.01 (molar ratio), recovered o The amount of dichlorobenzene used is 5 times of the mass of 3-(2-chlorophenyl)-5-methyl-4-isoxazole formic acid.

[0019] 3-(2-Chlorophenyl)-5-methyl-4-isoxazolecarboxylic acid, tetrabutylurea and recovered o-dichlorobenzene were added to the reaction kettle, and after stirring evenly, drop it within 45 minutes at room temperature Add the o-dichlorobenzene solution of two (trichloromethyl) carbonates, and the others are the same as in Example 2. The yield is 96.6%, the melting point is 41-42°C, and the content (HPLC) is 99.0%.

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Abstract

3-(2-chlorophenyl)-5-methyl-4-isoxazole formyl chloride is a key intermediate body of cloxacillin. It uses bis (trichloromethyl) carbonate and makes it directly be reacted with 3-(2-chlorophenyl)-5-methyl-4-isoxazole formic acid instead of sulfur oxycchloride or phosphorus oxychloride or phosphorus pentachloride or phosphorus trichloride or phosgene or diphosgene to synthesize 3-(2-chlorophenyl)-5-methyl-4-isoxazole formyl chloride.

Description

technical field [0001] The present invention relates to a direct method of replacing thionyl chloride or phosphorus oxychloride or phosphorus pentachloride or phosphorus trichloride or phosgene or diphosgene with bis(trichloromethyl)carbonate [bis(trichloromethyl)carbonate] Prepare 3-(2-chlorophenyl)-5-methyl-4-isoxazole carboxylic acid chloride [3-( 2-chlorophenyl)-5-Met (hour yl isoxazole-4-carbonylChloride] chemical synthesis method, 3-(2-chlorophenyl)-5-methyl 4-isoxazolecarbonyl chloride is the key intermediate of cloxacillin . Background technique [0002] Before the present invention was made, the chemical synthesis method of prior art 3-(2-chlorophenyl)-5-methyl-4-isoxazole carboxylic acid chloride was based on sulfur oxychloride or phosphorus oxychloride or pentachloride Phosphorus or phosphorus trichloride and 3-(2-chlorophenyl)-5-methyl-4-isoxazolecarboxylic acid are used as raw materials to react, such as US 2996501 (1961). The disadvantage of this process is ...

Claims

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Application Information

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IPC IPC(8): C07D261/18
Inventor 苏为科李永曙许进
Owner ZHEJIANG UNIV OF TECH
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