Diisobutylaluminum hydride → 2-Bromo-5-(hydroxymethyl)phenol

To a suspension of 4-bromo-3-hydroxybenzoic acid methyl ester 70 (6.97 g, 30.2 mmol) in dichloromethane (360 mL) at 0° C. was added DIBALH (100 mL of a 1 M in toluene, 100 mmol) portionwise. Significant gas evolution was observed. The resultant mixture was warmed to room temperature and stirred for 2.75 h. After this time, the reaction mixture was quenched by the addition of saturated aqueous sodium potassium tartrate (600 mL) and saturated aqueous ammonium chloride (100 mL). The resultant biphasic mixture was stirred vigorously for 2 h, and then extracted with dichloromethane (3×). The organic layers were dried over Na2SO4 and filtered, to give 71. 1H NMR (400 MHz CDCl3) δ: 1.70 (br s, 1H), 4.64 (d, J=4.5 Hz, 2H), 5.55 (br s, 1H), 6.82 (dd, J=8.0 Hz, 2.0 Hz, 1H), 7.04 (d, J=2.0 Hz, 1H), 7.44 (d, J=8.0 Hz, 1H). MS (EI) m/z (M−H−) 201.

1. customAfter this time, the reaction mixture was quenched by the addition of saturated aqueous sodium potassium tartrate (600 mL) and saturated aqueous ammonium chloride (100 mL)
2. stirringThe resultant biphasic mixture was stirred vigorously for 2 h
3. extractionextracted with dichloromethane (3×)
4. dry with materialThe organic layers were dried over Na2SO4
5. filtrationfiltered

ORD-Eintrag

ord-af2196ffe5a34087ba07134d0b8f48fa

Quelldatensatz

uspto-grants-2009_12

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07635695B2