4-Chloro-2-fluorophenylboronic acid synthesis
- Product Name:4-Chloro-2-fluorophenylboronic acid
- CAS Number:160591-91-3
- Molecular formula:C6H5BClFO2
- Molecular Weight:174.37
121-43-7
1996-29-8
7732-18-5
160591-91-3
To a 2L round bottom flask was added 1-bromo-4-chloro-2-fluorobenzene (50 g, 238.7 mmol) and anhydrous tetrahydrofuran (900 ml), and the mixture was cooled to -78°C with stirring. Slowly n-butyllithium (2.5 M hexane solution, 100 ml, 250 mmol) was added dropwise and stirred continuously for 1 hour at this temperature. Subsequently, trimethyl borate (31.9 ml, 286 mmol) was added slowly and the reaction was continued for 30 minutes. After completion of the reaction, 1N aqueous hydrochloric acid solution (600 ml) was added and gradually warmed up to room temperature while stirring. The organic layer was separated, dried with anhydrous magnesium sulfate and filtered. The solvent was removed by distillation under reduced pressure, and the concentrated product was extracted with a mixture of chloroform and hexane solvents, and finally purified by recrystallization to afford 4-chloro-2-fluorophenylboronic acid (33.7 g, 193.3 mmol) in 81% yield.
121-43-7
381 suppliers
$14.00/25mL
1996-29-8
339 suppliers
$6.00/5g
7732-18-5
564 suppliers
$13.50/100ML
160591-91-3
212 suppliers
$6.00/250mg
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
5419-55-6
396 suppliers
$12.00/5g
1996-29-8
339 suppliers
$6.00/5g
160591-91-3
212 suppliers
$6.00/250mg
121-43-7
381 suppliers
$14.00/25mL
6797-79-1
200 suppliers
$9.00/5g
160591-91-3
212 suppliers
$6.00/250mg