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ChemicalBook CAS DataBase List 4-Chloro-2-fluorophenylboronic acid
160591-91-3

4-Chloro-2-fluorophenylboronic acid synthesis

3synthesis methods
-

Yield:160591-91-3 81%

Reaction Conditions:

Stage #1: 1-bromo-4-chloro-2-fluorobenzenewith n-butyllithium in tetrahydrofuran;hexane at -78; for 1 h;
Stage #2: Trimethyl borate in tetrahydrofuran;hexane; for 0.5 h;
Stage #3: waterwith hydrogenchloride in tetrahydrofuran;hexane at 20;

Steps:

3.1 1) Preparation of compound 1

A 2 L round bottom flask was charged with 1-bromo-4-chloro-2-fluorobenzene(1-bromo-4-chloro-2-fluorobenzene, 50 g, 238.7 mmol)And anhydrous tetrahydrofuran 900 ml was added and the mixture was cooled to -78°C with stirring.N-butyl lithium (2.5 M hexane solution; 100 ml, 250 mmol)And the mixture was stirred for 1 hour.Trimethylborate (31.9 ml, 286 mmol) was slowly added thereto,After 30 minutes, 600 ml of a 1N hydrogen chloride aqueous solution was addedThe temperature was raised to room temperature while stirring.The organic layer was separated, dried over anhydrous magnesium sulfate, and filtered. The mixture was distilled under reduced pressure, concentrated, and extracted with chloroform and hexaneAnd recrystallized to obtain Compound 1 (33.7 g, 193.3 mmol) in a yield of 81%.

References:

KR101680413,2016,B1 Location in patent:Paragraph 0129-0132

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