Sodium ethoxide → 2,3-dihydro-6-fluoro-4-cyano-2-(2-phenylethyl)-4H-1-benzopyran
Reaction equation
[F:1][C:2]1[CH:3]=[CH:4][C:5]2[O:10][CH:9]([CH2:11][CH2:12][C:13]3[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=3)[CH2:8][C:7](=O)[C:6]=2[CH:20]=1.C1(C)C(S([CH2:30][N+:31]#[C-])(=O)=O)=CC=CC=1.[O-]CC.[Na+].[Na]>O1CCCC1.C(O)C>[C:30]([CH:7]1[C:6]2[CH:20]=[C:2]([F:1])[CH:3]=[CH:4][C:5]=2[O:10][CH:9]([CH2:11][CH2:12][C:13]2[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=2)[CH2:8]1)#[N:31]Participants
7
Reactant 4
Product 1
Reagents, catalysts & solvents 2
Procedure
2,3-dihydro-6-fluoro-2-(2-phenylethyl)-4H-1-benzopyran-4-one (8.9 gm) was dissolved in anhydrous tetrahydrofuran, and toluenesulfonylmethylisocyanide (12.9 gm) added, followed by freshly prepared sodium ethoxide in ethanol (prepared from sodium (1.5 gm) in ethanol (60 mL) and the mixture stirred at room temperature overnight. The mixture was then concentrated in vacuo, and the residue partitioned between ethyl acetate and H2O, and the organic layer washed with H2O, brine, dried, filtered and evaporated. The residue was purified by column chromatography (2:1 hexanes/diethyl ether) to yield 4-cyano-2,3-dihydro-6-fluoro-2-(2-phenylethyl)-4H-1-benzopyran (2.7 gm, ir: 2250 cm-1).
Workup
- concentrationThe mixture was then concentrated in vacuo
- customthe residue partitioned between ethyl acetate and H2O
- washthe organic layer washed with H2O, brine
- customdried
- filtrationfiltered
- customevaporated
- customThe residue was purified by column chromatography (2:1 hexanes/diethyl ether)
Sources & evidence
- ORD record
- ord-f5c5c904d22e4c2a848997a6458a2605
- Source dataset
- uspto-grants-1994_03
- Patent number
- US05294635
Reaction notes
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