Water → 3-methyl-4-oxo-5-(2-pyrrolidin-1-yl-ethyl)-4,5,6,7-tetrahydro-1H-pyrrolo[3,2-c]pyridine-2-carbaldehyde

Participants

Reaction Conditions

Reaction Steps

N,N-dimethylformamide (1.5 ml) was added slowly with phosphorus oxychloride (115 μl, 3.2 mmol) under an argon atmosphere while maintaining the temperature at 0° C. Upon completion of the addition, the mixture was stirred for 15 minutes at room temperature, and cooled down to 0˜5° C. in an ice-water bath. A mixture of 3-methyl-5-(2-pyrrolidin-1-yl-ethyl)-1,5,6,7-tetrahydro-pyrrolo[3,2-c]pyridin-4-one (719 mg, 2.91 mmol) in 3 ml of N,N-dimethylformamide was added dropwise to the above solution. Upon completion of the addition, the mixture was stirred for 2 hours at 0° C., added with cold water (20 ml) and stirred for another 5 minutes. The resulting mixture was adjusted to pH 12 with 10% aqueous sodium hydroxide solution and extracted with dichloromethane (30 ml×3). The combined organic extracts were washed with brine (15 ml), dried with anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography with triethylamine: methanol:dichloromethane (1:20:500) as eluents to give 3-methyl-4-oxo-5-(2-pyrrolidin-1-yl-ethyl)-4,5,6,7-tetrahydro-1H-pyrrolo[3,2-c]pyridine-2-carbaldehyde (411 mg, 51.37%) as a brown oil which was used as such.

Provenance & Evidence