Cesium carbonate → 1,1-dimethylethyl 7-(6-amino-5-nitropyridin-3-yl)-2,3-dihydro-1,4-benzoxazepine-4(5H)-carboxylate

Participants

Reaction Conditions

Reaction Steps

A suspension of 5-bromo-3-nitropyridin-2-amine (4.84 g, 22.2 mmol), (4-{[(1,1-dimethylethyl)oxy]carbonyl}-2,3,4,5-tetrahydro-1,4-benzoxazepin-7-yl)boronic acid (6.51 g, 22.2 mmol), dichloro[1,1-bis(diphenyl)phosphino]ferrocenepalladium (II) dichloromethane adduct (1.60 g, 10 mol %) in dioxane (75 mL) and water (15 mL) was degassed with nitrogen, and then cesium carbonate (14.46 g, 44.4 mmol) was added. The reaction mixture was stirred at 90° C. overnight. The mixture was cooled to room temperature, water (150 mL) was added and stirred for 30 min to give a precipitate. The product 1,1-dimethylethyl 7-(6-amino-5-nitropyridin-3-yl)-2,3-dihydro-1,4-benzoxazepine-4(5H)-carboxylate (8.1 g, 94% yield) was collected by filtration, dried under vacuum. MS (EI) for C19H22N4O5: 387.1 (MH+).

Provenance & Evidence