تفاعل #1833252

معادلة التفاعل

1,2,2-trifluorotrichloroethane

n-Butyllithium

2,2-Difluorobenzo[d][1,3]dioxole

1,2,2-Trifluorotrichloroethane

→

title compound

المردود 74.9%

4-Chloro-2,2-difluorobenzo[d][1,3]dioxole

المردود 74.9%

المذيبات

tetrahydrofuran

tetrahydrofuran

ظروف التفاعل

المعالجة

1. 1
   workup.ADDITIONwas added dropwise
2. 2
   أخرىthe temperature below −70° C
3. 3
   درجة الحرارةcooled to −65° C
4. 4
   workup.ADDITIONto remain between −60° C. and −65° C. during the addition
5. 5
   درجة الحرارةto warm to room temperature
6. 6
   أخرىpartitioned between diethyl ether and water
7. 7
   تركيزThe organic phase was concentrated

الإجراء التجريبي

2,2-Difluorobenzo[d][1,3]dioxole (6.3 g, 39.8 mmol) was dissolved in tetrahydrofuran (66 mL) and cooled to −78° C. n-Butyllithium (2.5 M solution in hexanes; 16.74 mL, 41.8 mmol) was added dropwise, keeping the temperature below −70° C. The reaction mixture was then stirred at −78° C. for 1 h to ensure complete deprotonation. 1,2,2-Trifluorotrichloroethane (14.93 g, 80 mmol) was dissolved in tetrahydrofuran (33 mL) and cooled to −65° C. The lithiate was transferred via cannula into the solution of 1,2,2-trifluorotrichloroethane at a rate that allowed the temperature to remain between −60° C. and −65° C. during the addition. The reaction mixture was then allowed to warm to room temperature and partitioned between diethyl ether and water. The organic phase was concentrated and the product was flashed through 100 g of silica gel using hexane as a solvent to provide the title compound as a clear oil (5.74 g, 74.8%): 1H NMR (400 MHz, CDCl3) δ 7.08 (dd, J=8.2, 1.4 Hz, 1H), 7.03 (t, J=8.0 Hz, 1H), 6.97 (dd, J=7.9, 1.5 Hz, 1H); EIMS m/z 192.

المصدر