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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 54938Generated: October 25, 2026

Hydrochloric Acid → 2-(4-Fluorophenyl)-3-(pyridin-4-yl)pyrazolo[1,5-a]pyrimidine

https://huagongshe.com/reaction/54938

Reaction equation

Participants

RoleNameHCIDCharge
ReactantHydrochloric AcidHCID 313—
ReactantTetramethoxypropaneHCID 66019—
ReactantSodium BicarbonateHCID 516892—
ReactantHCID 178509109HCID 178509109—
CatalystZincchlorideHCID 3007855—
SolventEthanolHCID 702—
Product2-(4-Fluorophenyl)-3-(pyridin-4-yl)pyrazolo[1,5-a]pyrimidineHCID 1995728087.6%

Reaction Steps

To a solution of 5-amino-3-(4-fluorophenyl)-4-(pyridin-4-yl)pyrazole (102 mg) in ethanol (3 ml) were added concentrated hydrochloric acid (50 μl ), zinc chloride (27 mg) and 1,1,3,3-tetramethoxypropane (72 mg) in that order. The mixture was refluxed for one hour, cooled, and poured into an aqueous saturated sodium bicarbonate solution. The separated oil was extracted with dichloromethane. The extract was washed with brine, dried and concentrated in vacuo. The residue was crystallized from a mixture of ethyl acetate and diethyl ether to yield 2-(4-fluorophenyl)-3-(pyridin-4-yl)pyrazolo[1,5-a]pyrimidine (102 mg).

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS05624931
Source datasetuspto-grants-1997_04
ORD IDord-ae2a07aaacbc4495a74969ee0c2cc6ff
Source noteuspto-grants-1997_04