Reference of 1260243-04-6,Some common heterocyclic compound, 1260243-04-6, name is Ethyl 5-amino-1H-pyrazole-4-carboxylate, molecular formula is C6H9N3O2, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.
Cs2CO3 (64.20 g, 197.20 mmol) was added to a solution of ethyl 5-amino-1H-pyrazole-4-carboxylate (20.40 g, 131.40 mmol) and ethyl-3-ethoxyacrylate (28.6 mL, 197.20 mmol) in DMF (250 mL). The reaction mixture was stirred at 110 C for 16 h. The mixture was cooled to room temp and the pH was adjusted to 4 by the addition of AcOH (80 mL). The mixture was concentrated in vacuo and the residue partitioned between CH2Cl2/H2O (1000 mL, 1:1). The organic layer was separated and the aqueous layer was extracted with CH2Cl2 (3 X 500 mL). The combined organics were washed with brine, dried (MgSO4) and concentrated. The crude residue was suspended in EtOH (300 mL) and heated to boiling. After cooling to room temperature the solid was collected by filtration, rinsed with EtOH, then Et2O and dried under vacuum to give ethyl 5-oxo-4,5-dihydropyrazolo[1,5-a]pyrimidine-3-carboxylate (25.16 g, 92 %). MS (ESI) calcd for C9H9N3O3 (m/z): 207.06; found: 208 [M+H].
The synthetic route of 1260243-04-6 has been constantly updated, and we look forward to future research findings.