Ammonia → 3,6-Dimethyl-3,4,9,10-tetrahydro-2,3,4,9-tetraaza-benzo[f]azulene

To a suspension of 3,6-dimethyl-4,9-dihydro-3H-2,3,4,9-tetraaza-benzo[f]azulen-10-one from Example E2.3 (2.35 g, 10.3 mmol) in anhydrous THF (100 ml) at 0° C. was added lithium aluminium hydride (1.56 g, 41.2 mmol), and the resulting suspension was heated at reflux for 18 h then allowed to cool to room temperature. A further portion of lithium aluminium hydride (781 mg, 20.6 mmol) was added, and the mixture was heated at reflux for 3 h. The mixture was cooled to 0° C., 35% ammonia solution (10 ml) was added dropwise over 15 min and the mixture was stirred at room temperature for 30 min. The resulting suspension was filtered through Celite® filter agent and the filtrate concentrated in vacuo. The residue was purified by flash chromatography on silica gel (eluant; 10% methanol:90% dichloromethane) to yield the title compound (1.60 g, 72%).

1. temperaturethe resulting suspension was heated
2. temperatureat reflux for 18 h
3. temperaturethe mixture was heated
4. temperatureat reflux for 3 h
5. temperatureThe mixture was cooled to 0° C.
6. filtrationThe resulting suspension was filtered through Celite®
7. filtrationfilter agent
8. concentrationthe filtrate concentrated in vacuo
9. customThe residue was purified by flash chromatography on silica gel (eluant; 10% methanol:90% dichloromethane)

ORD record

ord-da04e10e7a9944f6aed8b20d42e1163c

Source dataset

uspto-grants-2012_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08202858B2