Potassium Carbonate → 6-bromo-1-(cyclopropylmethyl)-7-phenyl-1H-pyrido[2,3-b][1,4]oxazin-2(3H)-one

Participants

Reaction Conditions

Reaction Steps

In a 15 mL reaction tube was added 6-bromo-7-phenyl-1H-pyrido[2,3-b][1,4]oxazin-2(3H)-one (300 mg, 0.983 mmol), (bromomethyl)cyclopropane (0.114 mL, 1.180 mmol) and potassium carbonate (408 mg, 2.95 mmol) in anhydrous N,N-dimethylformamide (1 mL) to give a brown suspension. This was stirred at 50° C. under a nitrogen atmosphere for 60 minutes. The reaction mixture was diluted with saturated sodium bicarbonate solution (5 mL) and extracted into ethyl acetate (3×5 mL). The combined organic phases were washed with 50:50 water:brine (3×5 mL), dried over Na2SO4, filtered and concentrated to dryness under reduced pressure to give a brown solid. This was purified by Biotage chromatography (25 g silica cartridge, cyclohexane:ethyl acetate, gradient elution from 90:10 to 20:80) to give the title compound as a beige solid (160 mg, 0.445 mmol, 45.3% yield). 1H NMR (500 MHz, CDCl3): 7.58-7.37 (5H, m), 7.32 (1H, s), 4.88 (2H, s), 3.81 (2H, d), 1.14-1.01 (1H, m), 0.60-0.53 (2H, m), 0.47-0.40 (2H, m).

Provenance & Evidence