Ethyl bromoacetate → HCID 86740882, compound

Participants

Reaction Steps

3-Benzylidene-6-hydroxy-1,2,3,9-tetrahydro-cyclopenta[b][1]benzopyran-9-one (1.5 g) was reacted with ethyl 2-bromo-acetate (1.67 g) in dimethylformamide (60 ml), in the presence of anhydrous K2CO3 (1.38 g), under stirring at room temperature for 3 hours. The reaction mixture was diluted with ice water containing NaH2PO4 and the precipitated product was filtered and washed with water: crystallization from CH2Cl2 /methanol gave (3-benzylidene-1,2,3,9-tetrahydro-9-oxo-cyclopenta[b][1]benzopyran-6-yloxy)acetic acid, ethyl ester, m.p. 152°-154° C. (1.75 g), which was dissolved in dimethylformamide (22 ml) and treated with 2N NaOH (11.5 ml) at room temperature for 2 hours. The reaction mixture was acidified with 2N HCl and then diluted with ice water: the precipitated product was filtered and washed with water until neutral. Crystallization from CHCl3 /ethanol gave 1.4 g of (3-benzylidene-1,2,3,9-tetrahydro-9-oxo-cyclopenta[b][1 ]benzopyran-6-yloxy)-acetic acid, m.p. 277°-279° C.

Provenance & Evidence