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| | 3-chloropyrazine-2-carboxaMide Basic information |
| Product Name: | 3-chloropyrazine-2-carboxaMide | | Synonyms: | 3-chloropyrazine-2-carboxaMide;3-Chloro-2-pyrazinecarboxaMide;3-Chloro-pyrazine-2-carboxylic acid amide;2-Pyrazinecarboxamide, 3-chloro- | | CAS: | 21279-62-9 | | MF: | C5H4ClN3O | | MW: | 157.56 | | EINECS: | | | Product Categories: | | | Mol File: | 21279-62-9.mol |  |
| | 3-chloropyrazine-2-carboxaMide Chemical Properties |
| Melting point | 187.0 to 191.0 °C | | storage temp. | under inert gas (nitrogen or Argon) at 2-8°C | | form | powder to crystal | | color | White to Orange to Green |
| | 3-chloropyrazine-2-carboxaMide Usage And Synthesis |
| Synthesis | Two methods for the synthesis of 3-chloropyrazine-2-carboxamide from 2-chloro-3-cyanopyrazine are described below:
The first method is based on the homolytic amidation reaction of 2-chloropyrazine, which is less effective. The procedure was as follows: 2-chloropyrazine (0.17 mol) was dissolved in formamide (3.7 mol), heated to 90 °C, and then ammonium peroxydisulfate (0.18 mol) was added in batches over a period of 1 hour. The reaction mixture was continued at 90 °C for 1 h, followed by standing for 24 h at room temperature. Upon completion of the reaction, the mixture was diluted with 100 mL of water, filtered, and the filtrate was continuously extracted with chloroform for 16 hours. A mixture of three positional isomers was obtained by rapid chromatography on silica gel stationary phase.
The second method used the partial hydrolysis reaction of 3-chloropyrazine-2-carbonitrile. The procedure was as follows: powdered 3-chloropyrazine-2-carbonitrile (0.104 mol) was slowly added to a mixture of concentrated hydrogen peroxide (0.95 mol) and water (195 mL) heated to 50 °C. The pH of the reaction mixture was adjusted to about 9 with 8% sodium hydroxide solution and the reaction temperature was maintained between 55 and 60°C. The reaction was stopped after 2.5 hours and cooled to 5°C. The precipitated crystals were collected by diafiltration and purified by recrystallization with ethanol. | | References | [1] Molecules, 2014, vol. 19, # 7, p. 9318 - 9338
[2] Molecules, 2017, vol. 22, # 2, |
| | 3-chloropyrazine-2-carboxaMide Preparation Products And Raw materials |
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