反应详情

温度

90 °C

Palladium (II) acetate (38 mg, 0.17 mmol) was added to a solution of 3-iodo-4-oxo-4,5,6,7-tetrahydro-pyrazolo[1,5-a]pyrazine-2-carboxylic acid ethyl ester (0.56 g 1.68 mmol), methylboronic acid (0.75 g, 12.6 mmol), 2-dicyclohexylphosphino-2′,4′,6′-triiso-propyl-1,1′-biphenyl (0.16 mg, 0.34 mmol) and potassium carbonate (0.69 g, 5.0 mmol) in toluene (15 mL) under nitrogen and the mixture was heated at 90° C. for 16 hours. Then the mixture was heated at 120° C. for 4 hours more. The mixture was diluted with a saturated Na2CO3 solution and extracted with DCM. The organic layer was separated, dried (MgSO4), filtered and the solvent evaporated in vacuo. The crude product was purified by flash column chromatography (silica; MeOH in DCM 0/100 to 10/90). The desired fractions were collected and the solvents evaporated in vacuo to yield 3-methyl-4-oxo-4,5,6,7-tetrahydro-pyrazolo[1,5-a]pyrazine-2-carboxylic acid ethyl ester (0.22 g, 58% yield).

1. temperatureThen the mixture was heated at 120° C. for 4 hours more
2. extractionextracted with DCM
3. customThe organic layer was separated
4. dry with materialdried (MgSO4)
5. filtrationfiltered
6. customthe solvent evaporated in vacuo
7. customThe crude product was purified by flash column chromatography (silica; MeOH in DCM 0/100 to 10/90)
8. customThe desired fractions were collected
9. customthe solvents evaporated in vacuo