Triphenylphosphine → HCID 67072065, compound

Participants

Reaction Conditions

Reaction Steps

4-Ethoxycarbonyl-2-iodothiazole (6.39 g) was suspended in 60 ml of triethylamine, and 253 mg of palladium acetate and 592 mg of triphenylphosphine, and 6.37 ml of ethynyltrimethylsilane were added to the suspension under an argon atmosphere, followed by stirring at 80° C. for 2 hr. The reaction solution was concentrated under the reduced pressure, ethyl acetate and brine were added to the concentrate, and the mixture was adjusted to pH 3.0 by the addition of 1 N aqueous hydrochloric acid. The mixture was extracted twice with ethyl acetate and was washed with brine. The organic layer was dried over anhydrous magnesium sulfate, was filtered, and was concentrated under the reduced pressure. The residue was purified by column chromatography on silica gel (hexane:ethyl acetate=5:1) to give 3.97 g of 2-(2-trimethylsilylethynyl)-4-ethoxycarbonylthiazole. This compound was dissolved in 30 ml of methanol, and the solution was cooled in ice. Potassium carbonate (220 mg) was added to the cooled solution, and the mixture was stirred at room temperature for 30 min. Brine was added to the reaction solution, and the mixture was extracted twice with ethyl acetate and was washed with brine. The organic layer was dried over anhydrous magnesium sulfate, was filtered, and was concentrated under the reduced pressure to give 2.50 g of 2-ethynyl-4-methoxycarbonylthiazole.

Provenance & Evidence