Potassium Carbonate → HCID 53873785, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 0.96 g of the partially purified 6-[(5-bromopentyl)oxy]-2,5-quinolinedipropanoic acid diethyl ester from the preceding example, 0.402 g (1.95 mmol) of 2,3-dihydro-7-hydroxy-8-propyl-4H-1-benzopyran-4-one, 1.08 g (7.8 mmol) of anhydrous granular potassium carbonate and 25 mL of 2-butanone was stirred at 90° C. for 18 hr. A second portion of 2,3-dihydro-7-hydroxy-8-propyl-4H-1-benzopyran-4-one (0.117 g, 0.57 mmol) was added and the reaction was continued for another 22.5 hr. The mixture was cooled and filtered through anhydrous magnesium sulfate and the solids were washed with ethyl acetate. The filtrate and washes were combined and concentrated under reduced pressure. The crude product was purified by flash chromatography on 110 g of silica gel, eluting with hexane-ethyl acetate (5:2) to give 0.66 g (54.8%) of the title compound as a white solid, mp 59°-61° C.

Provenance & Evidence