Cesium carbonate → Tert-butyl 8-(6-nitropyridin-3-yl)-3,8-diazabicyclo[3.2.1]octane-3-carboxylate

Participants

Reaction Conditions

Reaction Steps

A 250-mL single-neck round-bottomed flask equipped with a magnetic stirrer and a reflux condenser was charged with 1,4-dioxane (100 mL), 5-bromo-2-nitropyridine (2.5 g, 12.4 mmol), tert-butyl 3,8-diazabicyclo[3.2.1]octane-3-carboxylate(869 g, 4.1 mmol), Pd2(dba)3 (193 mg, 0.21 mmol), XantPhos (237 mg, 0.41 mmol), and cesium carbonate (2.7 g, 8.2 mmol). After three cycles of vacuum/argon flush, the mixture was stirred at 110° C. overnight. The reaction was cooled to room temperature. It was then filtered and the filtrate was evaporated in vacuo. The residue was purified by silica-gel column chromatography eluting with 3:1 petroleum ether/ethyl acetate to afford 152a (2.63 g, 66.8%) as a yellow solid. MS-ESI: [M+H]+ 335.2.

Provenance & Evidence