Cesium carbonate → HCID 86672034, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of (4-{[(1,1-dimethylethyl)oxycarbonyl}-2,3,4,5-tetrahydro-1,4-benzoxazepin-7-yl)boronic acid (example 1, step 2) (500 mg, 1.7 mmol), 5-bromopicolinaldehyde (380 mg, 2.0 mmol), cesium carbonate (1.66 g, 5.0 mmol), and dichloro[1,1-bis(diphenylphosphino]ferrocenepalladium (II) dichloromethane adduct (125 mg, 0.17 mmol) in dioxane (5.0 mL) and water (1.0 mL) was degassed with nitrogen, and then stirred at 90° C. with microwave irradiation for 30 min. The reaction mixture was cooled to room temperature, and partitioned between water and ethyl acetate. The aqueous layer was extracted with ethyl acetate (2×), the combined organic layers were washed with brine (1×), dried over sodium sulfate, filtered and concentrated. Column chromatography on silica (hexanes/ethyl acetate 4:1) provided 1,1-dimethylethyl 7-(6-formylpyridin-3-yl)-2,3-dihydro-1,4-benzoxazepin-4(5H)-carboxylate (580 mg, 96% yield) as a colorless solid. MS (EI) for C20H22N2O4: 355 (MH+).

Provenance & Evidence