tert-Butyl 4-carbamothioylpiperazine-1-carboxylate → 4-(2,4-Difluorophenyl)-5-(3-isopropyl-[1,2,4]triazolo[4,3-b]pyridazin-6-yl)-2-(piperazin-1-yl)thiazole

Participants

Reaction Steps

A mixture of 2-bromo-1-(2,4-difluorophenyl)-2-(3-isopropyl-[1,2,4]triazolo[4,3-b]pyridazin-6-yl)ethanone (0.61 g, 1.5 mmol; Preparation #A.2) and tert-butyl 4-carbamothioylpiperazine-1-carboxylate (Beta Pharma Inc, 0.341 g, 1.39 mmol) in EtOH (3 mL) was heated to reflux overnight. After cooling to ambient temperature, the crude mixture was partitioned between DCM and 1N aqueous HCl. The aqueous layer was basified with saturated aqueous Na2CO3 and extracted with DCM. The organics were dried over MgSO4, filtered, concentrated under reduced pressure, and purified by silica gel chromatography using DCM/MeOH (linear gradient, 100:0 to 90:10) to give the title compound (0.061 g, 10%): LC/MS (Table 1, Method a) Rt=2.31 min; MS m/z: 442.8 (M+H)+.

Provenance & Evidence