Potassium Carbonate → 5'-Oxazol-5-yl-[1,3']bipyridinyl-2-one

Participants

Reaction Conditions

Reaction Steps

To an oven-dried sealed tube containing a solution of 3-bromo-5-oxazol-5-yl-pyridine VIII-a (1.00 g, 4.44 mol) in degassed 1,4-dioxane (20 mL) was added 2-hydroxypyridine (507 mg, 5.33 mmol), K2CO3 (1.23 g, 1.78 mmol), Cut (169 mg, 0.899 mmol) and rac-trans-N,N′-dimethylcyclohexane diamine (280 μL, 1.78 mmol). The tube was flushed with argon and sealed then heated in an oil bath at 120° C. overnight. After cooling to RT, the mixture was filtered and the filter cake washed with 1,4-dioxane. The mixture was evaporated and the residue purified by column chromatography (2% to 5% EtOH in DCM) to give the desired product VIII-b as a beige solid (752 mg, 71%). 1H NMR (300 MHz, DMSO-d6) δ 9.06 (s, 1H), 8.68 (s, 1H), 8.60 (s, 1H), 8.29 (s, 1H), 7.95 (s, 1H), 7.80 (dd, J=6.8, 1.6 Hz, 1H), 7.57 (ddd, J=8.8, 6.6, 1.9 Hz, 1H), 6.54 (d, J=9.2 Hz, 1H), 6.39 (t, J=6.7 Hz, 1H).

Provenance & Evidence