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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 2195505Generated: November 2, 2026

Methanesulfonic Acid → HCID 66766901, compound

https://huagongshe.com/reaction/2195505

Reaction equation

Participants

RoleNameHCIDCharge
ReactantMethanesulfonic AcidHCID 6395—
Reactant3,4-dihydro-2H-pyranHCID 8080—
ReactantEthyl 5-hydroxy-1H-indazole-6-carboxylateHCID 66766802—
SolventDichloromethaneHCID 6344—
SolventTetrahydrofuranHCID 8028—
ProductHCID 66766901HCID 6676690177.2%

Reaction Steps

To a solution of ethyl 5-hydroxy-1H-indazole-6-carboxylate (15.5 g, 75 mmol) in DCM (100 mL) and THF (100 mL) containing methanesulfonic acid (721 mg, 7.5 mmol) is added a solution of 3,4-dihydro-2H-pyran (6.6 g, 79 mmol) in DCM (20 mL) dropwise at RT. The resulting solution is stirred at RT overnight. After the solvent is removed, EtOAc (500 mL), saturated aqueous sodium chloride (500 mL) and NaHCO3 (5 g) are added. The organic layer is separated, dried and concentrated. The residue is purified by silica gel column chromatography to afford the product (16.8 g, 77% yield). MS (m/z): 291.1 (M+H).

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUSRE043878E1
Source datasetuspto-grants-2012_12
ORD IDord-59db8290479847ba9958bc6270251dbd
Source noteuspto-grants-2012_12