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ChemicalBook CAS DataBase List 2,5-Dimethoxyphenylboronic acid
107099-99-0

2,5-Dimethoxyphenylboronic acid synthesis

7synthesis methods
-

Yield:107099-99-0 50%

Reaction Conditions:

Stage #1: 1-bromo-2,5-dimethoxybenzenewith n-butyllithium in tetrahydrofuran at -78; for 2 h;
Stage #2: Trimethyl borate in tetrahydrofuran at 20;

Steps:

3.1 Synthesis Example 3. Synthesis of Compound 140. Synthesis Example 3-(1). Synthesis of Intermediate 3-a

In a 1-L round-bottom flask reactor, 2-bromo-1,4-dimethoxybenzene (50 g, 230 mmol) and tetrahydrofuran (400 ml) were dissolved. After the mixture was cooled to -78° C., it was added with drops of N-butyl lithium (167 ml, 280 mmol). At the same temperature, the mixture was stirred for 2 hrs before the addition of trimethyl borate (36 ml, 320 mmol). Stirring was conducted overnight at room temperature. After completion of the reaction, 2 N HCl was dropwise added for acidification. Extraction with water and ethyl acetate gave an organic layer which was then dried over magnesium sulfate and concentrated in a vacuum. Recrystallization in heptane and toluene afforded . (20.8 g, 50%)

References:

US2017/18723,2017,A1 Location in patent:Paragraph 0157-0158

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