Dimethyl Sulfoxide → 5-(3-Methoxypropyl)-2-nitro-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrazine

A microwave vial equipped with a magnetic stirrer was charged with 1-(2-bromoethyl)-5-(chloromethyl)-3-nitro-1H-pyrazole 296c (600 mg, 2.2 mmol), 3-methoxypropan-1-amine (595 mg, 6.6 mmol), and DMSO (6 mL). It was heated at 120° C. under microwave irradiation for 0.5 h. The mixture was then cooled to room temperature and diluted with ethyl acetate (30 mL). The resulting mixture was washed with water (3×10 ml). The organic layer was dried and filtered. The filtrate was concentrated under pressure and the residue was purified by silica-gel column chromatography eluting with 30:1 dichloromethane/methanol to afford 309a (350 mg, 66%) as a yellow solid. MS-ESI: [M+H]+ 241.1

1. customA microwave vial equipped with a magnetic stirrer
2. temperatureThe mixture was then cooled to room temperature
3. washThe resulting mixture was washed with water (3×10 ml)
4. customThe organic layer was dried
5. filtrationfiltered
6. concentrationThe filtrate was concentrated under pressure
7. customthe residue was purified by silica-gel column chromatography
8. washeluting with 30:1 dichloromethane/methanol

ORD-Eintrag

ord-1192ac4e50e741ed8d3e61d3bb84b98d

Quelldatensatz

uspto-grants-2014_12

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08921353B2