Reaction #1833229

Reaction equation

NH4Cl

sec-BuLi

2,2,4,6-Tetrafluorobenzo[d][1,3]dioxole

iodine

→

title compound

Yield 30.0%

2,2,4,6-Tetrafluoro-5-iodobenzo[d][1,3]dioxole

Yield 30.0%

Solvents

tetrahydrofuran

tetrahydrofuran

Conditions

Workup

1. 1
   workup.WAITAfter 2 h at −70° C.
2. 2
   Extractionextracted with ethyl ether
3. 3
   Dryingdried (Na2SO4)
4. 4
   Otherevaporated
5. 5
   OtherThe material was purified by reverse phase HPLC with 85% acetonitrile-water

Procedure

2,2,4,6-Tetrafluorobenzo[d][1,3]dioxole (500 mg, 2.6 mmol) was dissolved in dry tetrahydrofuran (7 mL), cooled to −70° C., treated dropwise with sec-BuLi (1.3 M; 2.1 mL, 2.7 mmol) and stirred for 1 h at −70° C. This mixture was treated dropwise with a solution of iodine (1.1 g, 4.4 mmol) in tetrahydrofuran (5 mL) over 10 min. After 2 h at −70° C., the mixture was treated with saturated NH4Cl, extracted with ethyl ether, dried (Na2SO4) and evaporated. The material was purified by reverse phase HPLC with 85% acetonitrile-water to give the title compound (250 mg; 30%): 1H NMR (400 MHz, CDCl3) δ 6.80-6.77 (d, J=8.7 Hz, 1H), 6.77-6.75 (d, J=8.7 Hz, 1H); 19F NMR (376 MHz, CDCl3) δ −48.72, −99.73, −132.62; EIMS m/z 320.

Source