Cesium carbonate → Tert-butyl 3-((5-chloro-2-methoxypyridin-3-yl)amino)azetidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-bromo-5-chloro-2-methoxypyridine (5.00 g, 33.7 mmol) in toluene (100 mL) was added tert-butyl 3-aminoazetidine-1-carboxylate (5.8 g, 18.5 mmol), Xantphos (650 mg, 1.12 mmol), Cs2CO3 (14.6 g, 44.9 mmol) and Pd2(dba)3 (514 mg, 0.562 mmol). The reaction mixture was stirred at 60° C. under nitrogen for 4 days. After cooling to RT, the reaction mixture was filtered, washed with ethyl acetate (100 mL), the organic layer washed with water (60 mL), brine (60 mL), dried over Na2SO4, filtered, and concentrated in vacuo. The residue was purified by flash chromatography (ethyl acetate/hexane) to obtain 5.6 g of tert-butyl 3-((5-chloro-2-methoxypyridin-3-yl)amino)azetidine-1-carboxylate as a white-yellow oil (80%): 1H NMR (400 MHz, CDCl3) δ 7.39 (d, J=2.2 Hz, 1H), 6.36 (d, J=2.2 Hz, 1H), 4.52 (d, J=6.5 Hz, 1H), 4.24 (dd, J=8.9, 7.1 Hz, 2H), 4.05 (m, 1H), 3.89 (s, 3H), 3.70 (dd, J=9.1, 4.8 Hz, 2H), 1.37 (s, 9H); MS (ES) m/z 314 (M+H).

Provenance & Evidence