Water → Ethyl 7-chloro-2H-chromene-3-carboxylate

Participants

Reaction Steps

4-Chloro-2-hydroxybenzaldehyde (Acta. Chem. Scand., Vol. 53, p. 258, 1999) (510 mg) was dissolved in tetrahydrofuran (40 ml), sodium hydride (60% in oil, 157 mg) was added, and the mixture was stirred at room temperature for 2 hours. A tetrahydrofuran solution (10 ml) of ethyl 2-diethylphosphonoacrylate (J. Org. Chem., Vol. 43, P. 1256, 1978) (769 mg) was added to the reaction mixture, and the resultant mixture was stirred at room temperature for 2 hours and then heated overnight under reflux. After the reaction mixture was cooled to room temperature, water and diethyl ether were added to conduct liquid separation. After the resultant organic layer was dried over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure, and the residue was purified by column chromatography on silica gel (hexane:ethyl acetate=10:1) to obtain the title compound (247 mg).

Provenance & Evidence