Lithium Hydroxide → 3-{7-[3-(4-Acetyl-3-hydroxy-2-propylphenoxy)propoxy]-2-methyl-4-oxo-8-propyl-3,4-dihydro-2H-1-benzopyran-2-yl}propanoic acid

Participants

Reaction Steps

A solution of 0.5 g (9.5 mmole) of lithium hydroxide in 10 ml of water was added to a solution of 2.2 g (3.9 mmole) of the title compound of Example 6 in 25 ml of tetrahydrofuran and 20 ml of methanol. After the reaction mixture was stirred for 3 hours at room temperature, the solvent was evaporated and water was added to the residue. After extracting with a small amount of diethyl ether, the aqueous layer was acidified with dilute hydrochloric acid and allowed to stand in the cold overnight. The solid was filtered, washed with water and recrystallized from ethyl acetate/hexane to yield 1.83 g of the title compound, mp. 80°-83°. Structure assignment was confirmed by nmr and infrared spectra and by elemental analysis. nmr (CDCl3) loss of ester CH3 (compare Example 6)

Provenance & Evidence