2-Aminophenol hydrochloride → HCID 22723448, compound

Diisobutylaluminum (100 mL of 1.0 M, 100 mmol) was added dropwise to a solution of dimethyl 2-methylbutanedioate (7.6 g, 48 mmol) in dichloromethane (15 mL) at −78° C., and the solution was stirred for 1 h. A suspension of 2-aminophenol HCl salt (6.6 g, 45 mmol) in water (110 mL) was added initially dropwise with vigorous stirring, then in small portions. About midway through the addition, the cooling bath was removed to help facilitate stirring. The mixture was stirred vigourously at room temperature overnight, then filtered over celite and the filter cake was washed several times with dichloromethane. The filtrate was separated, and the aqueous layer was extracted with dichloromethane (2×20 mL). The combined organics were washed with brine (50 mL), dried over MgSO4, concentrated and purified by column chromatography (0-40% EtOAc/hexane) to give 2-(3-methylpyrrol-1-yl)phenol (3.7 g, 48%) as a yellow oil. ESI-MS m/z calc. 173.2, found 174.3 (M+1)+; Retention time: 1.51 minutes (3 min run).

1. additionwas added initially dropwise with vigorous stirring
2. additionAbout midway through the addition
3. customthe cooling bath was removed
4. stirringto help facilitate stirring
5. stirringThe mixture was stirred vigourously at room temperature overnight
6. filtrationfiltered over celite
7. washthe filter cake was washed several times with dichloromethane
8. customThe filtrate was separated
9. extractionthe aqueous layer was extracted with dichloromethane (2×20 mL)
10. washThe combined organics were washed with brine (50 mL)
11. dry with materialdried over MgSO4
12. concentrationconcentrated
13. custompurified by column chromatography (0-40% EtOAc/hexane)

ORD record

ord-e26dcf069893470daf88329fa61ba377

Source dataset

uspto-grants-2016_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09365588B2