Hydrochloric Acid → Ethyl 3-(5-chlorothiophen-2-yl)-3-oxopropanoate

Participants

Reaction Steps

To a solution of 5-chlorothiophene-2-carboxylic acid (10.12 g, 62.24 mmol) in tetrahydrofuran (80 ml) was added 1,1′-carbonyldiimidazole (11.1 g, 68.5 mmol) at room temperature and the mixture was stirred as it was for 6 hrs. Monoethyl malonate monomagnesium salt (9.81 g, 34.2 mmol) was added to this mixture at room temperature and the mixture was stirred at 60° C. for 3 hrs. The reaction solution was diluted with ethyl acetate and water, and acidified with conc. hydrochloric acid. The ethyl acetate layer was separated, and the aqueous layer was extracted with ethyl acetate. The collected organic layer was dried over anhydrous sodium sulfate and the solvent was evaporated under reduced pressure. The obtained crude product was purified by silica gel column chromatography (hexane/ethyl acetate=6/1) to give the objective substance.

Provenance & Evidence