Tetrahydrofuran → 1-Chloro-2-fluoro-4-vinylbenzene
Reaction equation
[H-].[Na+].[Cl:3][C:4]1[CH:11]=[CH:10][C:7]([CH:8]=O)=[CH:6][C:5]=1[F:12].[CH2:13]1COCC1>[Br-].C[P+](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1>[Cl:3][C:4]1[CH:11]=[CH:10][C:7]([CH:8]=[CH2:13])=[CH:6][C:5]=1[F:12]Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Procedure
Sodium hydride (8.549 g, 213.7 mmol, 60% suspension in mineral oil) was added portionwise to a cold (0° C.) solution of 4-chloro-3-fluorobenzaldehyde (26.07 g, 164.4 mmol) and methyltriphenylphosphonium bromide (70.48 g, 197.3 mmol) in THF (400 mL). The reaction mixture was allowed to warm up to room temperature overnight. The solids were removed by filtration, and the filter cake was washed with ether. The filtrate was concentrated (water bath about 20° C.), and the residue was suspended in hexanes and stirred for 30 minutes. The solids (mostly PPh3O) were removed by filtration, and the filter cake was washed with hexanes. The filtrate was concentrated, and the crude product was purified by column chromatography, eluting with hexanes/ethyl acetate (25:1) to give 1-chloro-2-fluoro-4-vinylbenzene (12.1 g, 47%) as an oil. 1H NMR (400 MHz, CDCl3) δ 7.33 (m, 1H), 7.18 (m, 1H), 7.10 (m, 1H), 6.63 (m, 1H), 5.74 (d, J=17.4 Hz, 1H), 5.32 (d, J=10.8 Hz, 1H).
Workup
- customThe solids were removed by filtration
- washthe filter cake was washed with ether
- concentrationThe filtrate was concentrated (water bath about 20° C.)
- customThe solids (mostly PPh3O) were removed by filtration
- washthe filter cake was washed with hexanes
- concentrationThe filtrate was concentrated
- customthe crude product was purified by column chromatography
- washeluting with hexanes/ethyl acetate (25:1)
Sources & evidence
- ORD record
- ord-558fd8993d494693b5fec7a33af882ac
- Source dataset
- uspto-grants-2016_02
- Patent number
- US09259470B2
Reaction notes
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