Stannane, tributyl(1-ethoxyethenyl)- → Tert-butyl 4-(7-(bis((2-(trimethylsilyl)ethoxy)methyl)amino)-6-(1-ethoxyvinyl)-3-(6-phenylpyridin-3-yl)pyrazolo[1,5-a]pyrimidin-5-yl)piperidine-1-carboxylate

Participants

Reaction Steps

To a pressure flask were charged compound tert-butyl 4-(7-(bis((2-(trimethylsilyl)ethoxy)methyl)amino)-6-bromo-3-(6-phenylpyridin-3-yl)pyrazolo[1,5-a]pyrimidin-5-yl)piperidine-1-carboxylate (intermediate from Scheme-10A) (13.66 g, 16.86 mmol), tributyl (1-ethoxyvinyl)tin (11.4 mL, 33.74 mmols) and dioxane (150 ml). The flask was degassed with Ar briefly, capped and heated at 100 C with stirring overnight. After cooling, the reaction mixture was concentrated. The residue was taken into ether (200 ml), washed with 0.5 M KF (50 ml), brine and dried (MgSO4). After solvent was removed under reduced pressure, the residue was purified on silica. Elution with EtOAc in hexanes (0-30%) gave compound tert-butyl 4-(7-(bis((2-(trimethylsilyl)ethoxy)methyl)amino)-6-(1-ethoxyvinyl)-3-(6-phenylpyridin-3-yl)pyrazolo[1,5-a]pyrimidin-5-yl)piperidine-1-carboxylate (11.55 g, 85%) as yellow form.

Provenance & Evidence