1106869-99-1Relevant articles and documents
Preparation method of 3-formyl-4-methylphenylboronic acid
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Paragraph 0024; 0026-0027; 0028; 0030; 0031; 0032; 0034-0035, (2020/12/15)
The invention discloses a preparation method of 3-formyl-4-methylphenylboronic acid. The method comprises the following steps of: adding 2-methyl-5-bromobenzaldehyde into a reaction vessel under the protection of nitrogen, adding a mixed solution of toluene and ethylene glycol, adding p-toluenesulfonic acid, carrying out heating reflux reaction, then performing desolventizing and rectifying to obtain a pure product of 2-methyl-5-bromobenzaldehyde diethyl acetal; dropwise adding tetrahydrofuran containing the pure product of 2-methyl-5-bromobenzaldehyde diethyl acetal and tributyl borate into tetrahydrofuran containing magnesium chips under the protection of nitrogen, carrying out heating reflux reaction, adding sulfuric acid to adjust the pH value to 2-4 after the reaction is finished, andperforming stirring to obtain a solution containing white solid; and adding an organic solvent into the obtained solution containing the white solid for extraction, combining all organic phases, carrying out reduced pressure rectification, recovering the solvent, and carrying out kettle bottom solid phase recrystallization to obtain the 3-formyl-4-methylphenylboronic acid. The method has the advantages of wide raw material sources, low production cost and mild reaction conditions, and is suitable for large-scale production and application.