Reacción #1833232

ord-4ad6a2e5c18f464fa31f2640b42e432b

Ecuación de reacción

[Cl-].[NH4+]
NH4Cl
CC1Oc2ccc(Br)cc2O1
5-Bromo-2-methylbenzo[d][1,3]dioxole
[Li][CH2]CCC
n-BuLi
[Cl-].[Na+]
NaCl
CC(C)OB1OC(C)(C)C(C)(C)O1
2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane
CC1Oc2ccc(B3OC(C)(C)C(C)(C)O3)cc2O1
title compound
Rendimiento 59.3%
CC1Oc2ccc(B3OC(C)(C)C(C)(C)O3)cc2O1
4,4,5,5-Tetramethyl-2-(2-methylbenzo[d][1,3]dioxol-5-yl)-1,3,2-dioxaborolane
Rendimiento 59.3%

Condiciones de reacción

Temperatura
-70°CELSIUS
Condiciones detalladas
See reaction.notes.procedure_details.

Tratamiento posterior

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

Procedimiento

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.

Fuente

DOI: 10.6084/m9.figshare.5104873.v1Patente: US09149038B2uspto-grants-2015_10