Sodium Carbonate → 6-(3-Bromo-5-fluorophenyl)-4,4-dimethyl-1,4-dihydrobenzo[d][1,3]oxazin-2-one
Reaction equation
[CH3:1][C:2]1([CH3:16])[C:7]2[CH:8]=[C:9](B(O)O)[CH:10]=[CH:11][C:6]=2[NH:5][C:4](=[O:15])[O:3]1.[Br:17][C:18]1[CH:23]=[C:22]([F:24])[CH:21]=[C:20](Br)[CH:19]=1.C(=O)([O-])[O-].[Na+].[Na+]>COCCOC.O.C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1>[Br:17][C:18]1[CH:19]=[C:20]([C:9]2[CH:10]=[CH:11][C:6]3[NH:5][C:4](=[O:15])[O:3][C:2]([CH3:16])([CH3:1])[C:7]=3[CH:8]=2)[CH:21]=[C:22]([F:24])[CH:23]=1Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 3
Conditions
- Temperature
- 85 °C
Procedure
A mixture of (1,4-dihydro-4,4-dimethyl-2-oxo-2H-3,1-benzoxazin-6-yl)boronic acid (2.22 g, 10 mmol), 1,3-dibromo-5-fluorobenzene (3.05 g, 12 mmol), tetrakis(triphenylphosphine)palladium (0) (0.6 g, 0.52 mmol), and sodium carbonate (2.2 g, 21 mmol) in a mixture of DME and water (70 mL/15 mL) was degassed to remove the oxygen and then heated at 85° C. under a blanket of nitrogen for 3 hours. The reaction mixture was cooled to ambient temperature and quenched with a saturated aqueous ammonium chloride solution (20 mL). Ethyl acetate (100 mL) was added and organic layer was separated. The aqueous layer was extracted with ethyl acetate (3×30 mL). The combined organic layers were washed with brine and dried with MgSO4. The solvent was removed in vacuo and the residue was purified by a silica gel flash chromatography (hexane:ethyl acetate/1:1) to give 6-(3-bromo-5-fluorophenyl)-4,4-dimethyl-1,4-dihydrobenzo[d][1,3]oxazin-2-one as a white solid (1.4 g, 40%): mp 182-183° C.; 1H-NMR (DMSO-d6) δ10.36 (s, 1H, D2O exchangeable), 7.78 (s, 1H), 7.58-7.65 (m, 3H), 7.49 (dd, 1H, J=8.3, 1.8 Hz), 6.96 (d, 1H, J=8.5 Hz), 1.69 (s, 6H); 19F-NMR (DMSO-d6) δ−112.46 (m, 1F); MS (CI) m/z 352([M+H]+, 78%), 350([M+H]+, 75%). Anal. Calc. For C16H13BrFNO2: C, 54.88; H, 3.74; N, 4.00. Found: C, 54.83; H, 3.82; N, 3.95.
Workup
- customwas degassed
- customto remove the oxygen
- temperatureThe reaction mixture was cooled to ambient temperature
- customquenched with a saturated aqueous ammonium chloride solution (20 mL)
- additionEthyl acetate (100 mL) was added
- customorganic layer was separated
- extractionThe aqueous layer was extracted with ethyl acetate (3×30 mL)
- washThe combined organic layers were washed with brine
- dry with materialdried with MgSO4
- customThe solvent was removed in vacuo
- customthe residue was purified by a silica gel flash chromatography (hexane:ethyl acetate/1:1)
Sources & evidence
- ORD record
- ord-d57d0957d5624764bb881d28fc14fa42
- Source dataset
- uspto-grants-2002_08
- Patent number
- US06436929B1
Reaction notes
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