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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 2209205Generated: October 30, 2026

Hydrochloric Acid → 6-Chloro-4-methoxypyrazolo[1,5-a]pyrazine-3-carboxylic acid

https://huagongshe.com/reaction/2209205

Reaction equation

Participants

RoleNameHCIDCharge
ReactantHydrochloric AcidHCID 313—
ReactantMethanolHCID 887—
ReactantWaterHCID 962—
ReactantMethyl 4-(benzyloxy)-6-chloropyrazolo[1,5-a]pyrazine-3-carboxylateHCID 117843324—
SolventTetrahydrofuranHCID 8028—
Product6-Chloro-4-methoxypyrazolo[1,5-a]pyrazine-3-carboxylic acidHCID 117843031—

Reaction Steps

methyl 4-(benzyloxy)-6-chloropyrazolo[1,5-a]pyrazine-3-carboxylate (5.35) (894 mg, 2.81 mmol) was suspended in THF (7.5 mL), water (2.5 mL), and MeOH (2.5 mL). After stifling at 30° C. for 5 h, HPLC demonstrated one primary product. The reaction mixture was acidified with aqueous HCl and was partitioned between water, EtOAc and 2-Me-THF. The phases were separated and the aqueous phase was extracted 3 times with a mixture of EtOAc and 2-Me-THF. The combined organic phase was concentrated to afford crude 6-chloro-4-methoxypyrazolo[1,5-a]pyrazine-3-carboxylic acid that was used without further purification. LCMS-ESI+ (m/z): [M+H]+ calcd for C8H7ClN3O3: 228.0; found: 228.1.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS09376441B2
Source datasetuspto-grants-2016_06
ORD IDord-bac56baf6aa946759ca9c99a53035ce2
Source noteuspto-grants-2016_06