Hydrochloric Acid → Darolutamide

Participants

Reaction Steps

Sodium borohydride (0.930 g, 24.57 mmol) and EtOH (105 ml) were placed in to the reaction flask under nitrogen atmosphere. (S)-3-acetyl-N-(1-(3-(3-chloro-4-cyano-phenyl)-1H-pyrazol-1-yl)propan-2-yl)-1H-pyrazole-5-carboxamide (15 g, 37.8 mmol) was added in small portions to keep temperature below 25° C. After 3.5 h sodium borohydride (0.07 g, 1.85 mmol) was added and the mixture was stirred for additional 60 min to complete the reaction. 16 ml of ˜10% HCl in EtOH was added carefully to set pH to 3.5 and the mixture was stirred overnight at RT. Water (30 ml) was added and the stirring was continued for 3 h. The precipitate was filtered, washed with 2×10 ml of cold water:EtOH (1:1) and dried under vacuum to obtain 12.2 g of the title compound. 1H-NMR (400 MHz, DMSO-d6): δ 1.12 (, 3H), 1.39 (d, 3H), 4.24-4.52 (m, 3H), 4.76-4.86 (m, 1H), 5.42 (d, 1H), 6.42 (bs., 1H), 6.94 (d, 1H), 7.82 (d, 1H), 8.00 (bs, 2H), 8.09 (bs, 1H), 8.20 (d, 1H), 13.05 (bs, 1H).

Provenance & Evidence