Sodium Hydroxide → (E)-3-{4-[8-Cyclopropyl-3,4-dimethylspiro[2H-1-benzopyran-2, 1'-cyclopropane]-6-yl]ethynyl-phenyl}-2-methyl-acrylic acid

Participants

Reaction Conditions

Reaction Steps

A solution of (E)-3-{4-[8-cyclopropyl-3,4-dimethylspiro[2H-1-benzopyran-2,1′-cyclopropane]-6-yl]ethynyl-phenyl}-2-methyl-acrylic acid ethyl ester (Intermediate 3, 0.06 g, 0.13 mmol) in ethanol (2 mL) was treated with a 1M solution of sodium hydroxide (0.5 mL, 0.5 mmol) and the resulting reaction mixture was heated at 55° C. for 4 h. The reaction mixture was cooled to ambient temperature and the volatiles were evaporated in vacuo to a residue that was neutralized with 5% hydrochloric acid and extracted with ethyl acetate. The organic phase was washed with water and brine, dried over anhydrous magnesium sulfate, filtered and evaporated in vacuo to afford the title product as a yellow solid after flash column chromatography over silica gel (230-400 mesh) (0.044 g, 82%).

Provenance & Evidence