Sodium borohydride → HCID 57495634, compound

Participants

Reaction Steps

To 228 mg (0.61 mmol) of 4-(1-Cyclopropyl-2,4-dioxo-1,3-diaza-spiro[4.6]undec-3-yl)-benzoic acid ethyl ester dissolved in 4 ml THF/Methanol 1:1 was added under ice-cooling 70 mg (1.84 mmol) of sodium borohydride. The reaction mixture was stirred for 2 h at RT and then additional 70 mg of sodium borohydride was added and the stirring was continued over night. The whole was concentrated under reduced pressure to dryness and the residue was dissolved in 2 ml of trifluoroacetic acid. To this ice-chilled solution was added again 70 mg of sodium borohydride. The reaction mixture was stirred for 1 h at RT and then the trifluoroacetic acid was removed under reduced pressure. The residue was taken up in EtOAc and washed with sodium bicarbonate solution and water. The crude product was purified by chromatography over silica gel with DCM/EtOAc 9:1 to give 103 mg of pure 4-(1-Cyclopropyl-2-oxo-1,3-diaza-spiro[4.6]undec-3-yl)-benzoic acid ethyl ester. MS (ESI): 357.3 (MH+).

Provenance & Evidence