تفاعل #304389

معادلة التفاعل

triisopropylborate

5-ethoxymethoxy-benzofuran

5-Ethoxymethoxy-benzofuran

n-butyllithium

→

desired compound ( 4 )

المردود 52.2%

5-Ethoxymethoxy-benzofuran-2-boronic acid

المردود 52.2%

المذيبات

THF

ظروف التفاعل

المعالجة

1. 1
   workup.WAITthe stirring was continued for additional 20 minutes at −78° C
2. 2
   أخرىThe reaction mixture was quenched with saturated ammonium chloride solution (10 mL)
3. 3
   workup.ADDITIONWater (10 mL) was added
4. 4
   استخلاصthe resulting mixture was extracted in diethyl ether (2×50 mL)
5. 5
   غسيلThe combined extracts were washed with brine
6. 6
   تجفيفdried over MgSO4
7. 7
   تركيزconcentrated under reduced pressure
8. 8
   أخرىPurification of the crude product
9. 9
   أخرىby recrystallization from ethyl acetate and hexane

الإجراء التجريبي

To a stirred solution of 5-ethoxymethoxy-benzofuran (3) (265 mg, 1.38 mmol) in THF (5 mL) at −78° C., n-butyllithium (2.5M solution in hexane, 0.56 mL, 1.44 mmol) was added drop wise. After the reaction mixture was stirred for 1 hour, triisopropylborate (0.635 mL, 2.76 mmol) was added slowly and the stirring was continued for additional 20 minutes at −78° C. The reaction mixture was quenched with saturated ammonium chloride solution (10 mL) and was allowed to warm to room temperature. Water (10 mL) was added and the resulting mixture was extracted in diethyl ether (2×50 mL). The combined extracts were washed with brine, dried over MgSO4, and concentrated under reduced pressure. Purification of the crude product by recrystallization from ethyl acetate and hexane afforded the desired compound (4) (170 mg) as a white solid.

المصدر