Hydrochloric Acid → (Z)-3-(7-cyclopentyloxy-4-methyloxycarbonylbenzo[b]furan-2-yl)-2-propenoic acid

Participants

Reaction Steps

To a well stirred solution of Methyl-2-formyl-7-cyclopentyloxybenzo[b]furan-4-carboxylate (21.0 g, 0.0868 moles) in toluene (250.0 mL) was added malonic acid (13.5 g, 0.1302 moles) and Piperidine (5.0 ml). The reaction mixture was then refluxed for 3-4 hours. Reaction mixture was cooled to room temperature, acidified with 10% aqueous HCl solution and extracted with ethyl acetate (2×250 mL). The combined organic layers were washed with water (2×100 mL) and dried over anhydrous sodium sulfate. Removal of solvent under vacuo gave product (19 g) as light yellow solid.

Provenance & Evidence