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 heated at reflux for six hours. The mixture was cooled to RT, quenched by slow addition of water and diluted with ethyl acetate. The mixture was washed with water, saturated sodium bicarbonate, brine, 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).