تفاعل #57065

معادلة التفاعل

3,4-difluoro-1,2-dibromo-benzene

furan

BuLi

→

24

المردود 70.0%

6,7-Difluoro-1,4-epoxy-1,4-dihydronaphthalene

المردود 70.0%

المذيبات

Et2O

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةto warm to room temperature
2. 2
   workup.WAITAfter 2 hours
3. 3
   أخرىthe reaction mixture was quenched with water dropwise
4. 4
   workup.ADDITIONwas poured into water
5. 5
   أخرىThe organic layer was separated
6. 6
   استخلاصthe aqueous layer was extracted three times with Et2O
7. 7
   غسيلThe combined organic layers were washed with brine
8. 8
   تجفيفdried over MgSO4
9. 9
   تركيزconcentrated
10. 10
    أخرىchromatographed (25% ethyl acetate:hexanes) on silica gel

الإجراء التجريبي

To 3,4-difluoro-1,2-dibromo-benzene (0.75 g, 2.78 mmol) and furan (1 mL, 14.7 mmol) in Et2O (15 mL) at −78° C. was added BuLi (1.1 mL, 2.5M in hexanes, 2.75 mmol) dropwise. The reaction was stirred for two hours at −78° C. and then was allowed to warm to room temperature. After 2 hours, the reaction mixture was quenched with water dropwise and then was poured into water. The organic layer was separated and the aqueous layer was extracted three times with Et2O. The combined organic layers were washed with brine, dried over MgSO4, concentrated and chromatographed (25% ethyl acetate:hexanes) on silica gel to give 24 (350 mg, 70%) as a colourless oil. Rf=0.21 on silica gel (20% ethyl acetate:hexanes); bp 40° C. @ 0.5 mmHg]; IR (neat, cm−1), 3017 (M), 1624 (s), 1465 (s), 1365 (s), 1253 (s), 1190 (m), 1040 (s), 857 (s). 1H NMR (400Mz, CDCl3) δ 7.06 (2H, dd, JH-F=7.7, 7.7 Hz), 7.01 (2H, s), 5.67 (2H, s); 13C NMR (400 MHz, CDCl3) δ 147.2 (dd, JC-F=247.9, 14.5 Hz), 145.1 (dd, JC-F=4.3, 4.3 Hz), 143.1, 110.8 (m), 82.1.HRMS calcd for C10H6O (M+): 180.0387. Found: 180.0394.

المصدر