Dimethylamine → 8-(1-hydroxyethyl)-N,N-dimethyl-2-((R)-2-methylmorpholino)-4-oxo-4H-chromene-6-carboxamide

Participants

Reaction Steps

2-(2,5-dioxopyrrolidin-1-yl)-1,1,3,3-tetramethylisouronium tetrafluoroborate (2.38 g, 3.96 mmol) was added portionwise to 8-(1-hydroxyethyl)-2-((R)-2-methylmorpholino)-4-oxo-4H-chromene-6-carboxylic acid (0.88 g, 2.64 mmol) and N-ethyl-N-isopropylpropan-2-amine (1.380 mL, 7.92 mmol) suspended in DCM (15 mL) at 10° C. under nitrogen. The resulting mixture was stirred at RT for 2 hrs. Dimethylamine (3.96 mL, 7.92 mmol) was then added at 10° C. and the resulting mixture was stirred at RT overnight. The mixture was poured onto a silica gel column and purified by flash chromatography eluting with 0 to 10% methanolic ammonia (7 N) in DCM. The solvent was evaporated to dryness to afford a foam which crystallised from ethyl acetate, the solid was collected by filtration and dried to a constant weight in a vacuum oven to afford 8-(1-hydroxyethyl)-N,N-dimethyl-2-((R)-2-methylmorpholino)-4-oxo-4H-chromene-6-carboxamide (0.800 g, 84%) as a white solid.

Provenance & Evidence