Water → 5H,6H,7H,8H-imidazo(1,5-a)pyridin-8-one

4-Hydroxy-1-(1-trityl-1H-imidazol-4-yl)butan-1-one (25.22 g) was dissolved in tetrahydrofuran (120 ml). Triethylamine (0.021 ml) and methanesulfonyl chloride (0.012 ml) were added and the mixture was stirred at room temperature for 1 h. Water (100 ml) was added under ice-cooling and the mixture was extracted with ethyl acetate. The organic layer was dried over magnesium sulfate and concentrated under reduced pressure. Acetonitrile (100 ml) was added and the mixture was refluxed under heating for 2 h. The reaction mixture was concentrated to dryness and the residue was purified by silica gel column chromatography (eluent; ethyl acetate:methanol=20:1→5:1) and washed with diethyl ether to give the title compound (2.10 g) as a pale-brown powder.

1. temperaturecooling
2. extractionthe mixture was extracted with ethyl acetate
3. dry with materialThe organic layer was dried over magnesium sulfate
4. concentrationconcentrated under reduced pressure
5. additionAcetonitrile (100 ml) was added
6. temperaturethe mixture was refluxed
7. temperatureunder heating for 2 h
8. concentrationThe reaction mixture was concentrated to dryness
9. customthe residue was purified by silica gel column chromatography (eluent; ethyl acetate:methanol=20:1→5:1)
10. washwashed with diethyl ether

ORD record

ord-88feccc3039946608784a39edaceb480

Source dataset

uspto-grants-2006_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07141598B2