672957-96-9Relevant academic research and scientific papers
Method for synthesizing 3-hydroxy-2-picolinic acid and derivatives thereof
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Paragraph 0048-0049, (2020/12/31)
The invention discloses an effective synthesis method of 3-hydroxy-2-picolinic acid and derivatives thereof. The method comprises an oxidation reaction, a cyanation reaction and a hydrolysis reaction.According to the oxidation reaction, 3-hydroxypyridine as shown in a formula I and derivatives thereof are used as substrates, and under the condition that an aqueous hydrogen peroxide solution is used as an oxidizing agent, the reaction is performed in glacial acetic acid at 60 DEG C in a nitrogen environment to obtain an oxidation product as shown in a structural general formula II. According to the cyanation reaction, the compound II and trimethylsilyl cyanide are taken as substrates and mixed with dimethylaminoformyl chloride in an ice bath, and then the reaction is conducted in dichloromethane at room temperature in the nitrogen environment to obtain a cyanation product as shown in a structural general formula III. According to the hydrolysis reaction, with the product as shown in the formula III as a substrate, the reaction is conducted in ethanol at a temperature of 80 DEG C under the condition of an aqueous sodium hydroxide solution to obtain the 3-hydroxy-2-picolinic acid asshown in the structural general formula IV and the derivatives thereof. The method is relatively economical, reaction universality is good, gram-level preparation is easy to carry out, the whole process can be industrialized, and reaction conditions are green.
