Citric Acid → HCID 86750430, compound

Participants

Reaction Steps

Three hundred milligrams of (1R, cis)-2,2-dimethyl-3(E)-[2-fluoro-2-(ethoxycarbonyl)ethenyl]-cyclopropane-1-carboxylic acid and 243 mg of N-(hydroxymethyl)dimethylmaleimide were dissolved in 4 ml of dry dichloromethane. To the resulting solution were added at room temperature 275 mg of N,N-dimethylaminopropyl-N'-ethylcarbodiimide hydrochloride (WSC), 200 μl of triethylamine and a catalytic amount of 4-dimethylaminopyridine. After stirring was continued for 12 hours at the same temperature, the reaction solution was poured into a cold aqueous dilute solution of citric acid, and extracted three times with dichloromethane. The dichloromethane layers were combined, washed with a saturated aqueous sodium chloride solution and dried over anhydrous magnesium sulfate. The solvent was then distilled off under reduced pressure. The residue was subjected to column chromatography on silica gel [eluent, n-hexane:ethyl acetate=3:1 (V/V)] to obtain 205 mg of the desired dimethylmaleimidomethyl (1R, cis)-2,2-dimethyl-3(E)-[2-fluoro-2-(ethoxycarbonyl) ethenyl]-cyclopropane-1-carboxylate [present compound (1)] as a colorless, transparent, viscous oily product (yield, 43%).

Provenance & Evidence