Boron tribromide → HCID 22899236, Verbindung
Reaktionsgleichung
B(Br)(Br)Br.[CH3:5][C:6]1([CH3:24])[O:11][C:10]2[C:12]3[CH:13]=[CH:14][C:15]([O:22]C)=[CH:16][C:17]=3[C:18]([C:20](=[O:21])[C:9]=2[CH2:8][CH2:7]1)=[O:19]>C(Cl)Cl>[CH3:5][C:6]1([CH3:24])[O:11][C:10]2[C:12]3[CH:13]=[CH:14][C:15]([OH:22])=[CH:16][C:17]=3[C:18]([C:20](=[O:21])[C:9]=2[CH2:8][CH2:7]1)=[O:19]Komponenten
4
Edukt 2
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 1
Reaktionsbedingungen
- Temperatur
- 20 °C
Versuchsvorschrift
Boron tribromide (15.0 mL, 1.0 M in CH2Cl2) was added to a solution of 54 (1.05 g, mmol) in anhydrous CH2Cl2 (40 mL) at 0° C. After stirring for 15 min, the mixture was allowed to warm to 20° C. and kept stirring for 2 h. Ice water (500 mL) was added, the mixture was extracted with CHCl3 (3×100 mL), the combined extracts were dried, and concentrated in vacuo. The residue was treated with concentrated H2SO4 (20 mL) at 20° C. The mixture was diluted with ice water (500 mL) and extracted with CHCl3 (3×100 mL). The combined extracts were reextracted with aqueous 5% NaHSO3 (3×150 mL). The aqueous extracts were acidified with concentrated HCl (100 mL), and extracted with CHCl3 (3×150 mL). The extracts were dried and concentrated to afford 55 (270 mg, 27%): 1H NMR (CDCl3) δ9.81 (OH, s), 7.64 (1H, d, J=8.5 Hz), 7.49 (1H, d, J=2.6 Hz), 7.06 (1H, dd, J=8.5, 2.6 Hz), 2.51 (2H, t, J=6.6 Hz), 1.84 (2H, t, J=6.6 Hz), 1.45 (6H, s); HRMS (m/z) calcd for C15H14O4 258.0892, found 258.0885.