Reaction #1833238

Reaction equation

NH4Cl

5-Bromo-6-chloro-2,2-difluorobenzo[d][1,3]dioxole

isopropylmagnesium lithium chloride

NaCl

2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane

→

title compound

Yield 101.8%

2-(6-Chloro-2,2-difluorobenzo[d][1,3]dioxol-5-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane

Yield 101.8%

Solvents

tetrahydrofuran

ethyl acetate

Conditions

Workup

1. 1
   workup.WAITwas continued for 45 min at 10-15° C
2. 2
   WashThe organic phase was washed with saturated NaCl (10 mL)
3. 3
   Dryingdried (Na2SO4)
4. 4
   Otherevaporated

Procedure

5-Bromo-6-chloro-2,2-difluorobenzo[d][1,3]dioxole (1.0 g, 3.7 mmol) was dissolved in dry tetrahydrofuran (7 mL), cooled to 0-5° C. and treated in portions with isopropylmagnesium lithium chloride (1.3 M; 3.0 mL, 3.9 mmol). After 30 min, 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (730 mg, 4.0 mmol) was added, and stirring was continued for 45 min at 10-15° C. Saturated NH4Cl (10 mL) was added and the mixture was shaken with ethyl acetate (20 mL) and saturated NaCl (10 mL). The organic phase was washed with saturated NaCl (10 mL), dried (Na2SO4) and evaporated to give the title compound as a white solid (1.2 g, qt): 1H NMR (400 MHz, DMSO-d6) δ 7.64 (s, 1H), 7.53 (s, 1H), 1.30 (s, 12H); 19F NMR (376 MHz, DMSO-d6) δ −48.97 (s); EIMS m/z 318.

Source