3-Dipropylamino-5-chloroformyichroman → 3-Dipropylamino-5-acetylchroman

Participants

Reaction Conditions

Reaction Steps

3-Dipropylamino-5-chloroformylchroman*HCl (4.42 g, 13.4 mmol), prepared from 3-dipropylamino-5-methyloxycarbonylchroman (Example 2) analogous to the procedure used in Example 3, in dry tetrahydrofuran (20 ml), was added to a pre-formed solution of lithium dimethylcuprate; prepared from MeLi and CuI, in 200 mL tetrahydrofuran at -78° C. The solution was stirred for 15 minutes at -78° C. and was then allowed to reach room temperature during 10 minutes. Then, 30 mL H20 was slowly added. The organic phase was decanted, dried with Na2SO4 and evaporated to dryness. The residue was purified by flash chromatography (silica gel) by elution with ethyl acetate/hexane 1:8. The title compound was crystallized as salt from ethyl acetate. Mp 106°-108° C. (oxalate).

Provenance & Evidence