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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 357799Generated: October 30, 2026

Hydrochloric Acid → 3,5-Dimethyl-2-thiophenecarboxylic acid

https://huagongshe.com/reaction/357799

Reaction equation

Participants

RoleNameHCIDCharge
ReactantHydrochloric AcidHCID 313—
ReactantMethyl iodideHCID 6328—
Reactant3-Methyl-2-thenoic acidHCID 90269—
ReactantButyllithiumHCID 178418339—
SolventWaterHCID 962—
SolventTetrahydrofuranHCID 8028—
Product3,5-Dimethyl-2-thiophenecarboxylic acidHCID 819558—

Reaction Conditions

Temperature-78 °C

Reaction Steps

3-Methyl-2-thiophenecarboxylic acid (7.11 g) was dissolved in tetrahydrofuran (100 ml), and the mixture was cooled to -78° C. n-Butyllithium (1.6M in hexane, 69 ml) was slowly added dropwise. The mixture was stirred at -78° C. for 1 hour, and iodomethane (6.2 ml) was added dropwise. The reaction mixture was warmed to room temperature, stirred at room temperature for 15 hours, poured into water, acidified with 1N hydrochloric acid and extracted with ethyl acetate. The extract was dried over anhydrous magnesium sulfate and concentrated under reduced pressure to give 3,5-dimethyl-2-thiophenecarboxylic acid (4.97 g) as crystals.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS05840917
Source datasetuspto-grants-1998_11
ORD IDord-2137988838944818ab61c7f73b9e3d20
Source noteuspto-grants-1998_11