2-(Dicyclohexylphosphino)biphenyl → Tert-butyl (6-(3-methylisothiazol-5-yl)-[1,2,4]triazolo[4,3-b]pyridazin-3-yl)methylcarbamate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A pressure vessel was purged with Ar and charged with tert-butyl (6-chloro-[1,2,4]triazolo[4,3-b]pyridazin-3-yl)methylcarbamate (5.00 g, 17.6 mmol), tris(dibenzylideneacetone)dipalladium (0) (0.807 g, 0.881 mmol), 2-dicyclohexylphosphinobiphenyl (0.618 g, 1.76 mmol). DMF (50 mL) was added, immediately followed by 3-methyl-5-(trimethylstannyl)isothiazole (6.46 g, 24.7 mmol). The reaction mixture was stirred at 100° C. for 1 h. Two more portions of tris(dibenzylideneacetone)dipalladium(0) (0.807 g, 0.881 mmol) and 2-dicyclohexylphosphinobiphenyl (0.618 g, 1.76 mmol) were added every hour for the first two hours of stirring. Reaction was then stirred was at 100° C. overnight, cooled to room temperature and concentrated in vacuo. Purification by MPLC (EtOAC/MeOH: 100/0 to 90/10) afforded the title compound (1.80 g, 30% yield). MS m/z=347.1 [M+H]+. Calc'd for C15H18N6O2S: 346.41

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