Ammonium Acetate → 6-(3,4-dimethoxyphenyl)pyrazolo[1,5-a]pyrazin-4(5H)-one
Reaction equation
C([O-])(=O)C.[NH4+:5].[CH3:6][O:7][C:8]1[CH:9]=[C:10]([C:16](=O)[CH2:17][N:18]2[C:22]([C:23]([O:25]CC)=O)=[CH:21][CH:20]=[N:19]2)[CH:11]=[CH:12][C:13]=1[O:14][CH3:15]>C(O)(=O)C>[CH3:6][O:7][C:8]1[CH:9]=[C:10]([C:16]2[NH:5][C:23](=[O:25])[C:22]3[N:18]([N:19]=[CH:20][CH:21]=3)[CH:17]=2)[CH:11]=[CH:12][C:13]=1[O:14][CH3:15]Participants
Conditions
- Temperature
- 110 °C
Procedure
Ammonium acetate (4.16 g, 54.0 mmol) was added to a solution of ethyl 1-(2-(3,4-dimethoxyphenyl)-2-oxoethyl)-1H-pyrazole-5-carboxylate 5.01 (195 mg, 0.61 mmol) in Acetic Acid (5.4 mL) at room temperature. Mixture was heated at 110° C. overnight. An additional 900 mg of ammonium acetate was added and mixture was heated at 110° C. for 3.5 hours, and then cooled to room temperature. Acetic acid was concentrated and residue was taken up in ethyl acetate and washed with 1:1 water/saturated NaHCO3 (aq). Layers were separated and aqueous was extracted with ethyl acetate. Combined organic layers were washed with 1:1 brine/saturated NaHCO3 (aq), dried (Na2SO4), filtered, and concentrated under reduced pressure to yield 6-(3,4-dimethoxyphenyl)pyrazolo[1,5-a]pyrazin-4(5H)-one 5.02, which was used without further purification.
Workup
- temperaturemixture was heated at 110° C. for 3.5 hours
- temperaturecooled to room temperature
- concentrationAcetic acid was concentrated
- washwashed with 1:1 water/saturated NaHCO3 (aq)
- customLayers were separated
- extractionaqueous was extracted with ethyl acetate
- washCombined organic layers were washed with 1:1 brine/saturated NaHCO3 (aq)
- dry with materialdried (Na2SO4)
- filtrationfiltered
- concentrationconcentrated under reduced pressure
Sources & evidence
- ORD record
- ord-4f4564490c8d46419ca05bb9cad3fb3a
- Source dataset
- uspto-grants-2016_06
- Patent number
- US09376441B2
Reaction notes
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