2-METHYL-4-(TRIFLUOROMETHYL)-1,3-THIAZOLE-5-CARBOXYLIC ACID synthesis
- Product Name:2-METHYL-4-(TRIFLUOROMETHYL)-1,3-THIAZOLE-5-CARBOXYLIC ACID
- CAS Number:117724-63-7
- Molecular formula:C6H4F3NO2S
- Molecular Weight:211.16
117724-62-6
117724-63-7
General procedure for the synthesis of 2-methyl-4-(trifluoromethyl)thiazole-5-carboxylic acid from ethyl 2-methyl-4-trifluoromethyl-5-thiazolecarboxylate: 115 g of ethyl 2-methyl-4-(trifluoromethyl)thiazole-5-carboxylate (0.102 mol) was dissolved in ethyl acetate at room temperature, and 50 g of 40% sodium hydroxide solution was added dropwise slowly into a reaction vessel with controlled The acceleration of the drop was controlled to maintain the temperature of the reaction system below 40 °C. After the dropwise addition, the reaction temperature was maintained and stirring was continued for 60 minutes. After the reaction was completed, the organic phase was separated and 10% hydrochloric acid solution was slowly added to the organic phase to adjust the pH value of the system to ≤2, at which time a large amount of solid precipitate precipitated. The precipitate was filtered and the filter cake was washed twice with 10% hydrochloric acid solution and subsequently dried in a vacuum oven. The resulting 2-methyl-4-(trifluoromethyl)thiazole-5-carboxylic acid was a light yellow solid with a yield of 21.5 g, a purity of 98.8% and a reaction yield of 98.70%.
62-55-5
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$9.00/5G
372-31-6
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117724-63-7
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$7.00/250mg
Yield:117724-63-7 90.8%
Reaction Conditions:
Stage #1: thioacetamide;ethyl 4,4,4-trifluoroacetoacetate in acetonitrile at 30; for 2.5 h;Large scale;
Stage #2: with tri-n-propylamine in acetonitrile at 30 - 40; for 4 h;Large scale;Further stages;Reagent/catalyst;
Steps:
1 Example 1
(1) into a chain130 kg of acetonitrile into the reactor,32 kg of thioacetamide was added with stirring,90 kg of ethyl trifluoroacetoacetate was added dropwise at 30 ° C,Drop finished,Continue to maintain the chain reaction for 2.5 hours. (2) to form a ringAfter the completion of the chain reaction,120 kg of tri-n-propylamine was added dropwise at 30 ° C,Dropping time for 1 hour,Drop finished,The temperature was raised to 70 ° C for 3 hours to form a ring-forming reaction. (3) hydrolysisAfter the ring-forming reaction,The acetonitrile, water and tri-n-propylamine were separated by vacuum distillation,Respectively, with water acetonitrile fraction and tri-n-propylamine fraction. After acetonitrile and tri-n-propylamine were removed,The reaction solution was cooled to 30 ° C,Add 45% NaOH alkaline solution 93kg,The temperature was raised to 55 ° C for 1 hour to carry out hydrolysis reaction.(4) acidificationAfter the hydrolysis reaction is complete,Cooling to 40 ,30% hydrochloric acid was added dropwise for acidification,Transferred to pH = 1-2, and then continue to cool to 0 ,Add 200kg of water,Stirring for 0.5 hours,Filter,Centrifugal,The filter cake is dried and dried2-methyl-4-trifluoromethyl-5-thiazolecarboxylic acid 82.0 kg,Content of 95.3%,Yield 90.8% (based on ethyl trifluoroacetoacetate).The raw materials used in the preparation are commercially available.
References:
CN106349183,2017,A Location in patent:Paragraph 0029-0047
117724-62-6
63 suppliers
$60.00/5mg
117724-63-7
182 suppliers
$7.00/250mg
372-31-6
476 suppliers
$5.00/10g
75-05-8
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$10.00/10g
117724-63-7
182 suppliers
$7.00/250mg
363-58-6
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62-55-5
566 suppliers
$9.00/5G
117724-63-7
182 suppliers
$7.00/250mg