Реакция #1833239

Уравнение реакции

NH4Cl

6-Bromo-4-methoxybenzo[d][1,3]dioxole

isopropylmagnesium lithium chloride

HCl

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

→

title compound

Выход 33.2%

2-(7-Methoxybenzo[d][1,3]dioxol-5-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane

Выход 33.2%

Растворители

ethyl acetate

tetrahydrofuran

Условия реакции

Обработка

1. 1
   Температураthe temperature was raised to 40° C.
2. 2
   ТемператураThe mixture was cooled to 20° C.
3. 3
   workup.STIRRINGstirred for 3 h
4. 4
   workup.STIRRINGwas stirred for 10 min
5. 5
   ПромывкаThe organic phase was washed with saturated NaCl (10 mL)
6. 6
   Сушкаdried (Na2SO4)
7. 7
   Другоеevaporated
8. 8
   ДругоеThe product was purified by flash chromatography with dichloromethane

Методика

6-Bromo-4-methoxybenzo[d][1,3]dioxole (1.5 g, 6.5 mmol, prepared according to Shirasaka, Tadashi; Takuma, Yuki; Imaki, Naoshi. Synthetic Communications 1990, 20, 1223-1232) was dissolved in dry tetrahydrofuran (25 mL), cooled to 5° C. and treated with isopropylmagnesium lithium chloride (1.3 M; 5.2 mL, 6.8 mmol). After 50 min at 10° C., the temperature was raised to 40° C. and stirred for 5 h. The mixture was cooled to 20° C., treated with 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (1.3 g, 7.1 mmol) and stirred for 3 h. The mixture was treated with saturated NH4Cl (2 mL), followed by 1 M HCl (8 mL) and ethyl acetate (20 mL), and then was stirred for 10 min. The organic phase was washed with saturated NaCl (10 mL), dried (Na2SO4) and evaporated. The product was purified by flash chromatography with dichloromethane to give the title compound as a white solid (600 mg; 33%): mp 86-88° C.; 1H NMR (400 MHz, CDCl3) δ 7.01 (d, J=0.5 Hz, 1H), 6.97 (d, J=0.8 Hz, 1H), 5.98 (s, 2H), 3.93 (s, 4H), 1.33 (s, 12H); EIMS m/z 278.

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