136192-85-3Relevant articles and documents
Method for synthesizing herbicide pyriminobac-methyl in paddy field
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Paragraph 0013; 0042-0043; 0054-0056; 0063; 0074-0076; 0083, (2021/02/24)
The invention belongs to the field of fine chemical engineering, and particularly relates to a preparation method of herbicide pyriminobac-methyl for a paddy fields. The preparation method comprises the following steps: synthesizing 3-hydroxy phthalic anhydride by using 3-chlorophthalic anhydride as a new raw material, protecting carbonyl by using diethyl malonate, hydrolyzing to obtain 2-acetyl-6-hydroxy benzoic acid, and esterifying to obtain 2-acetyl-6-hydroxy methyl benzoate; then carrying out imidization reaction with methoxyamine hydrochloride to obtain 2-hydroxy-6-(1-methoxy iminoethyl-methyl)-benzoate, and finally, condensing with 2-tosyl-4, 6-dimethoxypyrimidine to obtain pyriminobac-methyl. In the process of preparing pyriminobac-methyl, high-risk reagents such as n-butyllithiumare avoided, a large amount of wastewater generated by diazotization is avoided, the income is increased, and the environment is protected.
A practical synthesis of 6-acetylsalicylic acid methyl ester
Tamaru,Umezu,Maejima,Kageyama,Kimura
, p. 2749 - 2756 (2007/10/02)
A new and efficient synthesis of the title compound is reported. The method includes a regioselective ortho-lithiation step in none polar solvents at an ambient temperature and the overall yield for 5 steps is more than 70% from a commercially available 3-hydroxyacetophenone.