Phosphorus oxychloride → 8-Chloro-3-(1-methylpiperidin-4-yl)imidazo[1,5-a]pyrazine

Temperature

80 °C

To a solution of N-((3-chloropyrazin-2-yl)methyl)-1-methylpiperidine-4-carboxamide (6.51 mmol, 1.75 g) in acetonitrile (10 ml) was added phosphorus oxychloride (65.1 mmol, 6.36 ml) and this solution was heated at 80° C. for four hours. The reaction mixture was concentrated in vacuo and coevaporated with toluene. The residue was cooled in an ice bath and quenched with 7N ammonia in methanol (50 ml) and dichloromethane (50 ml). The solids were removed by filtration and the filtrate was concentrated. To the residue dichloromethane (50 ml) and of 7N ammonia in methanol (1 ml) was added. After 10 minutes at room temperature the solids were removed by filtration and the filtrate was concentrated. To the residue dichloromethane (50 ml) was added. After 10 minutes at room temperature the solids were removed by filtration and the filtrate was concentrated to give 8-chloro-3-(1-methylpiperidin-4-yl)imidazo[1,5-a]pyrazine (1.5 g).

1. concentrationThe reaction mixture was concentrated in vacuo
2. temperatureThe residue was cooled in an ice bath
3. customquenched with 7N ammonia in methanol (50 ml) and dichloromethane (50 ml)
4. customThe solids were removed by filtration
5. concentrationthe filtrate was concentrated
6. additionTo the residue dichloromethane (50 ml) and of 7N ammonia in methanol (1 ml) was added
7. customAfter 10 minutes at room temperature the solids were removed by filtration
8. concentrationthe filtrate was concentrated
9. additionTo the residue dichloromethane (50 ml) was added
10. customAfter 10 minutes at room temperature the solids were removed by filtration
11. concentrationthe filtrate was concentrated

ORD record

ord-db5e67fc968947a3ac4dec8674119d31

Source dataset

uspto-grants-2014_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08658794B2