Reaktion #1833220

Reaktionsgleichung

5-Bromo-4-chloro-2,2-difluorobenzo[d][1,3]dioxole

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

→

title compound

Ausbeute 101.8%

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

Ausbeute 101.8%

Lösungsmittel

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONtreated in portions with isopropylmagnesium chloride-lithium chloride complex solution (1.3 M; 3.1 mL, 4.1 mmol)
2. 2
   workup.WAITwas continued at 0-20° C. for 90 min
3. 3
   SonstigeThe reaction was quenched by addition of saturated NH4Cl (10 mL)
4. 4
   Extraktionthe mixture was extracted with ethyl acetate (30 mL)
5. 5
   ExtraktionThe aqueous phase was extracted again with ethyl acetate (15 mL)
6. 6
   Waschenthe combined organic phases were washed with saturated NaCl (15 mL)
7. 7
   Trocknendried (Na2SO4)
8. 8
   Sonstigeevaporated

Vorschrift

5-Bromo-4-chloro-2,2-difluorobenzo[d][1,3]dioxole (1.0 g, 3.7 mmol) was dissolved in dry tetrahydrofuran (12 mL), cooled to −20 to −30° C. and treated in portions with isopropylmagnesium chloride-lithium chloride complex solution (1.3 M; 3.1 mL, 4.1 mmol). After 90 min at −20 to 0° C., 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (830 μL, 750 mg, 4.1 mmol) was added, and stirring was continued at 0-20° C. for 90 min. The reaction was quenched by addition of saturated NH4Cl (10 mL), and the mixture was extracted with ethyl acetate (30 mL). The aqueous phase was extracted again with ethyl acetate (15 mL), and the combined organic phases were washed with saturated NaCl (15 mL), dried (Na2SO4) and evaporated to give the title compound as a white solid (1.2 g, ca. 100%): 1H NMR (400 MHz, CDCl3) δ 7.52 (d, J=8.1 Hz, 1H), 6.99-6.94 (m, 1H), 1.36 (s, 12H); 19F NMR (376 MHz, CDCl3) δ −49.62 (s); EIMS m/z 318.

Quelle