Réaction #1833232

Équation de réaction

NH4Cl

5-Bromo-2-methylbenzo[d][1,3]dioxole

n-BuLi

NaCl

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

→

title compound

Rendement 59.3%

4,4,5,5-Tetramethyl-2-(2-methylbenzo[d][1,3]dioxol-5-yl)-1,3,2-dioxaborolane

Rendement 59.3%

Solvants

tetrahydrofuran

ethyl acetate

Conditions de réaction

Traitement

1. 1
   Séchagedried (Na2SO4)
2. 2
   Autreevaporated
3. 3
   AutreThe material was purified by chromatography on silica with a 0-30% ethyl acetate-hexane gradient

Mode opératoire

5-Bromo-2-methylbenzo[d][1,3]dioxole (1.0 g, 4.7 mmol, prepared as described in Matyus, Peter; Magyar, Kalman; Pihlavista, Marjo; Gyires, Klara; Haider, Norbert; Wang, Yinghua; Woda, Patrick; Dunkel, Petra; Toth-Sarudy, Eva; Turos, Gyoergy, WO2010029379) was dissolved in dry tetrahydrofuran (10 mL), cooled to −70° C. and treated with n-BuLi (2.5 M; 2.1 mL, 4.7 mmol) over 5 min. After 1 h, 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (1.1 g, 6.0 mmol) was added and the mixture was stirred for 90 min at −70 to −30° C. After addition of saturated NH4Cl (5 mL), the mixture was shaken with ethyl acetate (40 mL) and saturated NaCl (10 mL), dried (Na2SO4) and evaporated. The material was purified by chromatography on silica with a 0-30% ethyl acetate-hexane gradient to give the title compound (730 mg, 59%): 1H NMR (400 MHz, CDCl3) δ 7.33 (dd, J=7.7, 1.1 Hz, 1H), 7.18 (d, J=0.9 Hz, 1H), 6.77 (d, J=7.8 Hz, 1H), 6.25 (q, J=5.0 Hz, 1H), 1.66 (d, J=4.9 Hz, 3H), 1.32 (s, 12H); EIMS m/z 262.

Source