Sulfuric Acid → HCID 19921956, compound

Participants

Reaction Steps

To a solution of 1.93 g (3.23 mmol) of 4-[[5-[(3,4-dihydro-4-oxo-8-propyl-2H-1-benzopyran-7-yl)oxy]pentyl]oxy]-3-(3-ethoxy-3-oxopropyl)benzenepentanoic acid ethyl ester from the preceding example, in 30 mL of tetrahydrofuran and 30 mL of water, was added 0.407 g (9.71 mmol) of lithium hydroxide monohydrate and the resulting solution was stirred at room temperature for 46 hr. The reaction mixture was acidified with 60 mL of 3N aqueous sulfuric acid, and worked-up with ethyl acetate in the usual manner. The crude product was purified by flash chromatography on 500 g of silica gel, eluting with hexane-ethyl acetate (1:1) affording 1.07 g (61.0%) of the title compound as a white solid, mp 101°-104° C.

Provenance & Evidence