Application of 3398-16-1, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 3398-16-1, name is 4-Bromo-3,5-dimethylpyrazole belongs to pyrazoles-derivatives compound, it is a common compound, a new synthetic route is introduced below.
To a dry three-necked flask with a magnetic rotor was added 4-bromo-3,5-dimethylpyrazole (3.5714 g, 20 mmol, 98%, 1.0 eq.), phenylboronic acid (2.9552 g, 24 mmol, 99%, 1.2 equivalents),Palladium acetate (0.1123 g, 0.5 mmol, 0.025 equivalent), ligand S-Phos (0.5027 g, 1.2 mmol, 98%, 0.06 equivalent), 1,4-dioxane (60 mL) and potassium carbonate (8.2920 g, 60 mmol, 3.0 eq.) of aqueous solution (20 mL).Nitrogen was bubbled for 15 minutes and then the reaction flask was placed in a 115 C oil bath.After stirring for 15 hours, the reaction was monitored by thin layer chromatography. It was cooled to room temperature and extracted with dichloromethane (20 mL×3).All organic phases were combined and dried over anhydrous sodium sulfate.Filtration, concentration, and purification of the crude product by flash chromatography on silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 3/1 – 1/2) to give 3,5-dimethyl-4-phenyl -1H-imidazole,The white solid was 3.0773 g, and the yield was 89%.
The synthetic route of 4-Bromo-3,5-dimethylpyrazole has been constantly updated, and we look forward to future research findings.
Reference:
Patent; Zhejiang University of Technology; Ruisheng Optoelectric Science And Technology (Changzhou) Co., Ltd.; Li Guijie; Dai Jianxin; She Yuanbin; Chen Shaohai; (127 pag.)CN108659050; (2018); A;,
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