Hydrochloric Acid → 4-(6-Cyano-4-(methoxycarbonyl)chroman-7-yloxy)-3-methylbenzoic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of K2CO3 (0.026 g, 0.19 mmol), methyl 6-cyano-7-fluoro-3,4-dihydro-2H-chromene-4-carboxylate (0.040 g, 0.17 mmol), and tert-butyl 4-hydroxy-3-methylbenzoate (0.039 g, 0.19 mmol) in 0.5 ml NMP was heated under argon at 120° C. for 24 hours. The reaction was cooled, poured into 10% aqueous HCl, and extracted with ethyl acetate. The organic extracts were dried with sodium sulfate and purified on silica gel. Elution with 25% ethyl acetate-hexanes provided material that still contained impurities. The mixture was deprotected with to 1:1 trifluoracetic acid-dichloromethane to provide the title compound (13 mg, still impure) which was used directly in the next step.

Provenance & Evidence