Dimethylformamide → HCID 21034896, compound

Participants

Reaction Steps

To anhydrous N,N-dimethylformamide (3.46 mL, 43.5 mmol) at 0° C. was added phosphorus oxychloride (1.83 mL, 19.2 mmol) dropwise. The mixture was warmed to room temperature and stirred for 30 minutes. The mixture was cooled in an ice-bath, and 6-acetoxy-7-methoxy-1-(3-ethoxy-benzyl)-1H-isoquinoline-2-carboxylic acid ethyl ester (3.7 mg, 8.70 mmol) in dichloromethane (8 mL) was added dropwise. After addition was complete, the mixture was heated on an oil bath for 4 hrs at 80° C. The mixture was cooled to 0° C. and a solution of potassium acetate (5.26 g, 52.2 mmol) in water (10 mL) was added slowly. The mixture was then heated at 80° C. for 20 minutes. The mixture was cooled, poured into water and diluted with dichloromethane (60 mL). The organic layer was washed water (2×80 mL), saturated aqueous sodium bicarbonate solution (50 mL), saturated aqueous sodium chloride solution (50 mL), dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo to afford a crude oil. Flash chromatography (Merck Silica gel 60, 70–230 mesh, 20% ethyl acetate/hexane) afforded 6-acetoxy-1-(3-ethoxy-benzyl)-4-formyl-7-methoxy-1H-isoquinoline-2-carboxylic acid ethyl ester as a colorless oil (1.0 g, 25% yield).

Provenance & Evidence