Hydrochloric Acid → HCID 21477008, compound

Participants

Reaction Steps

In an atmosphere of argon, 4.80 g of methyl 2-methoxy-4-propanoylaminobenzoate was dissolved in 50 ml of tetrahydrofuran and, at room temperature, 1.9 ml (20.2 mmol) of borane dimethylsulfide complex was added in small portions. After 1 hour of reflux, and excess reagent was decomposed with dilute hydrochloric acid under ice-cooling. The reaction solution was extracted with chloroform, the resulting organic layer was washed with water and saturated brine, dried over anhydrous sodium sulfate and concentrated under a reduced pressure. Then, the resulting residue was purified by silica gel column chromatography (chloroform:methanol=100:1) to give 3.19 g of methyl 2-methoxy-4-propylaminobenzoate. Next, in an atmosphere of argon, this compound and 2.5 ml of pyridine were dissolved in 50 ml of methylene chloride, and 2.1 ml of anhydrous trifluoroacetic acid was slowly added dropwise under ice-cooling. After 12 hours of stirring at room temperature, the reaction solution was poured in ice water, stirred for a while and then extracted with methylene chloride. The organic layer was washed with water and saturated brine, dried over anhydrous sodium sulfate and concentrated under a reduced pressure. Then, the resulting residue was purified by silica gel column chromatography (chloroform:methanol=200:1) to give 3.88 g of methyl 2-methoxy-4-(propyltrifluoroacetyl)aminobenzoate.

Provenance & Evidence