Hydrochloric Acid → 5-Fluoro-8-methoxychroman-6-carboaldehyde

Participants

Reaction Conditions

Reaction Steps

To a 130 ml THF solution containing 3.6 g of 5-fluoro-8-methoxychromane and 4.2 ml of N,N,N′,N′,N″-pentamethyldiethylenetriamine there was added dropwise 8 ml of n-butyllithium (2.55 M, hexane solution) at −74° C. After stirring at −74° C. for 1 hour, N-formylmorpholine was added. Stirring was continued for 1 hour at room temperature, and then 1N hydrochloric acid was added to the reaction mixture while cooling on ice, and the mixture was extracted with ethyl acetate and dried over anhydrous magnesium sulfate. The desiccant was filtered out and the filtrate was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate-heptane system) to obtain the target compound (1.50 g) as a colorless solid.

Provenance & Evidence