Sodium hydride → 2-(3-(Benzyloxy)-4-bromo-5-methoxyphenyl)-5-methyloxazole
Reaction equation
[CH2:1]([O:8][C:9]1[CH:10]=[C:11]([CH:18]=[C:19]([O:22][CH3:23])[C:20]=1[Br:21])[C:12]([NH:14][CH2:15][C:16]#[CH:17])=[O:13])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[H-].[Na+]>O1CCOCC1>[CH2:1]([O:8][C:9]1[CH:10]=[C:11]([C:12]2[O:13][C:16]([CH3:17])=[CH:15][N:14]=2)[CH:18]=[C:19]([O:22][CH3:23])[C:20]=1[Br:21])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1Participants
4
Procedure
To a solution of 3-(benzyloxy)-4-bromo-5-methoxy-N-(prop-2-yn-1-yl)benzamide (0.455 g, 1.22 mmol) in dioxane (12 mL) was added sodium hydride (60% wt, 0.146 g, 3.65 mmol) and the mixture was heated at reflux for six hours. The mixture was cooled to room temperature, quenched by slow addition of water, and diluted with ethyl acetate. The mixture was washed with water, saturated sodium bicarbonate, brine, then dried over magnesium sulfate and concentrated. Flash column chromatography (12 g silica, 2% ethyl acetate in DCM) provided 2-(3-(benzyloxy)-4-bromo-5-methoxyphenyl)-5-methyloxazole (198 mg) as an off-white solid. MS=374 (M+1). 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 7.55 (d, J=7.58 Hz, 2H), 7.43 (t, J=7.33 Hz, 2H), 7.32-7.39 (m, 2H), 7.27 (d, J=2.02 Hz, 1H), 6.89 (d, J=1.01 Hz, 1H), 5.27 (s, 2H), 4.02 (s, 3H), 2.44 (d, J=1.52 Hz, 3H).