Hydrochloric Acid → 2,6-Dichloro-4-hydroxybenzaldehyde

Temperatur

-78 °C

To a solution of 4-(tert-butyldimethylsilanyloxy)-2,6-dichlorobenzaldehyde (15.51 g, 55.9 mmol) in THF (80 mL) at −78° C. was added sec-butyllithium (41.14 mL, 57.6 mmol) dropwise over 25 min and the mixture was allowed to stir at −78° C. for 1.5 h. To the mostly yellow suspension was added DMF (6.47 mL, 83.9 mmol) and the yellow solution was allowed to stir at −78° C. for 5 h. To the reaction mixture was added MeOH (1 mL) and 1N HCl (60 mL) and allowed to warm to ambient temperature for 18 h. The brown solution was brought to pH 4, extracted with EtOAc, washed with water, brine, and dried with Na2SO4. A solid precipitated from the organic layer and was filtered and rinsed with DCM to give 2,6-dichloro-4-hydroxybenzaldehyde as white solid. MS (m/z) 191.0 (M+1); 1H NMR (DMSO-d6, 400 MHz) δ 11.45 (s, 1H), 10.24 (s, 1H), 6.93 (s, 2H).

1. stirringto stir at −78° C. for 5 h
2. temperatureto warm to ambient temperature for 18 h
3. extractionextracted with EtOAc
4. washwashed with water, brine
5. dry with materialdried with Na2SO4
6. customA solid precipitated from the organic layer
7. filtrationwas filtered
8. washrinsed with DCM

ORD-Eintrag

ord-2318a95fdc72427d9006bdb8d0215786

Quelldatensatz

uspto-grants-2012_07

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08222248B2