Hydrochloric Acid → ethyl 8-chloro-4-hydroxy-2-oxo-2',3',5',6'-tetrahydro-4H-spiro[naphthalene-1,4'-pyran]-3-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of (Z)-ethyl 4-(2-chloro-6-(3-ethoxy-1-hydroxy-3-oxoprop-1-enyl)phenyl)-tetrahydro-2H-pyran-4-carboxylate (0.38 g, 0.99 mmol) in 5 mL EtOH was treated with NaOEt (freshly made from 0.1 g Na and 5 mL EtOH), and stirred at 60° C. for 2 hours. The mixture was cooled to room temperature and diluted with 100 mL EtOAc, neutralized with 5N HCl to pH 5, washed with water (20 mL), saturated NaCl (20 mL), dried over anhydrous sodium sulfate and concentrated. The concentrate was purified by column chromatography (10-40% EtOAc/hexane) to give 0.27 g yellow solid. MS m/e: (M+H)+ 337.

Provenance & Evidence