123-32-0, Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 123-32-0, name is 2,5-Dimethylpyrazine, A new synthetic method of this compound is introduced below.
In a 500-L reactor equipped with a reflux condenser, 250 kg of water and 20 kg of 2,5-dimethylpyrazine were added.Potassium permanganate 4.0kg, heated to 82C, kept at 80C for 1.6h, the solution purple faded and cooled to 76C,Then add 4.0kg of potassium permanganate, slowly warming to 82C, and hold at 82C for 1.6h.The solution purple faded and then incubated for 2.5 hours, and the temperature was reduced to 22 DEG C.; the filter cake was filtered, the filter cake was washed with 12 kg of water, and the filtrate was combined;The combined filtrate is first concentrated under normal pressure, distilled out of water and pyrazine solution (recovery application), after about 82% steaming,Diverted under reduced pressure to dryness; which distilled out of the filtrate 250kg, containing 2,5-dimethyl pyrazine 17kg;Add 15kg of water to the steamed kettle and raise the temperature to 52C to fully dissolve it; then pump it to a neutralization kettle., Adjust the pH to 2.5 with 1+1 sulfuric acid at about 6Kg, and extract with butanone (80Kg x 3) 3 times at 52 C to combine the organic phases;The organic phase was allowed to stand for 24 hours and a small amount of water was removed in the lower layer. The upper organic layer was degassed to dryness at atmospheric pressure.Add 10kg of water to heat and dissolve it, and while it is hot, the filtrate is cooled to 0C, crystallized, and suction filtered.The crude product was dried to 3.6kg; recrystallized from butanone to give 3.2kg of light yellow crystalline powder of 5-methylpyrazine-3-carboxylic acid.The yield was 81.6% and the purity was 99.4%.
The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.
Reference:
Patent; Changzhou Engineering Polytechnic College; Chen Huiru; Chen Wenhua; Huang Yibo; Zhang Yuxiu; (7 pag.)CN108017586; (2018); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem