Ethyl Acetate → 6-(3-chloro-4-fluorophenyl)-2,4,4-trimethyl-1,4-dihydro-2H-3,1-benzoxazine

HRID 2120740Notes

Reaction equation

HRID 2120740 reaction equation
Br[C:2]1[CH:3]=[CH:4][C:5]2[NH:10][CH:9]([CH3:11])[O:8][C:7]([CH3:13])([CH3:12])[C:6]=2[CH:14]=1.[Cl:15][C:16]1[CH:17]=[C:18](B(O)O)[CH:19]=[CH:20][C:21]=1[F:22].C(=O)([O-])[O-].[Na+].[Na+].C(OCC)(=O)C>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>[Cl:15][C:16]1[CH:17]=[C:18]([C:2]2[CH:3]=[CH:4][C:5]3[NH:10][CH:9]([CH3:11])[O:8][C:7]([CH3:13])([CH3:12])[C:6]=3[CH:14]=2)[CH:19]=[CH:20][C:21]=1[F:22]

Participants

8

Conditions

Temperature
85 °C

Procedure

A mixture of 6-bromo-2,4,4-trimethyl-1,4-dihydro-2H-3,1-benzoxazine (3.0 g, 11.7 mmol), 3-chloro-4-fluorobenzeneboronic acid (3.1 g, 17.6 mmol), tetrakis(triphenylphosphine)palladium (0) (0.67 g, 0.59 mmol), and sodium carbonate (3.72 g, 35.1 mmol) in DME (80 mL) and water (40 mL) was subject to a blanket of nitrogen flow for 15 minutes at 50° C. and then was heated at 85° C. under nitrogen for 1 hour. The reaction was cooled to room temperature and ethyl acetate (200 mL) was added. The organic layer was washed twice with aqueous ammonium chloride (50 mL) and once with brine (50 mL), dried over sodium sulfate and concentrated to a yellow solid. The solid was triturated with ether (25 mL) and hexane (25 mL), collected on a filter, and dried to give 6-(3-chloro-4-fluorophenyl)-2,4,4-trimethyl-1,4-dihydro-2H-3,1-benzoxazine (1.87 g, 35%) as a yellow solid: mp 173-175° C.; 1H-NMR (DMSO-d6) δ 7.79 (dd, 1H, J=6.84, 2.14 Hz), 7.60-7.57 (m, 1H), 7.43-7.39 (m, 2H), 7.29 (dd, 1H, J=8.12, 2.14 Hz), 6.62 (d, 1H, J=8.54 Hz), 6.40 (s, 1H), 4.79 (q, 1H, J=5.55 Hz), 1.53 (s, 3H), 1.48 (s, 3H), 1.28 (d, 3H, J=5.55 Hz); MS (ES) m/z 306/308([M+H]+).

Workup

  1. temperatureThe reaction was cooled to room temperature
  2. washThe organic layer was washed twice with aqueous ammonium chloride (50 mL) and once with brine (50 mL)
  3. dry with materialdried over sodium sulfate
  4. concentrationconcentrated to a yellow solid
  5. customThe solid was triturated with ether (25 mL) and hexane (25 mL)
  6. customcollected on a filter
  7. customdried

Sources & evidence

ORD record
ord-f437e18c2f194e238ea4115a40507345
Source dataset
uspto-grants-2004_02
Patent number
US06693103B2

Reaction notes

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