3-[5-Hydroxy-2-(4-hydroxyphenyl)-benzofuran-7-yl]-acrylamide → 3-[5-Hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-yl]-acrylonitrile
Reaction equation
[OH:1][C:2]1[CH:3]=[C:4]([CH:18]=[CH:19][C:20]([NH2:22])=O)[C:5]2[O:9][C:8]([C:10]3[CH:15]=[CH:14][C:13]([OH:16])=[CH:12][CH:11]=3)=[CH:7][C:6]=2[CH:17]=1>CN(C=O)C.P(Cl)(Cl)(Cl)=O>[OH:1][C:2]1[CH:3]=[C:4]([CH:18]=[CH:19][C:20]#[N:22])[C:5]2[O:9][C:8]([C:10]3[CH:11]=[CH:12][C:13]([OH:16])=[CH:14][CH:15]=3)=[CH:7][C:6]=2[CH:17]=1Participants
4
Procedure
A solution of 3-[5-hydroxy-2-(4-hydroxyphenyl)-benzofuran-7-yl]-acrylamide 61 (0.07 g, 0.24 mmol) in DMF (5 mL) and phosphorous oxychloride (0.11 mL) was heated at 65° C. for 2 hours. Then ice was added to the reaction mixture and the product extracted into ethyl acetate. The organic layer was dried over MgSO4 and the solvent removed in vacuo. The crude product was submitted for reverse phase prep HPLC. The product was isolated to give 0.007 g of 3-[5-hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-yl]-acrylonitrile 64: 1H NMR (DMSO-d6) δ 9.90 (s, 1 H), 9.48 (s, 1 H), 7.82 (d, 2 H, J=8.6 Hz), 7.79 (d, 1 H, J=16.7 Hz), 7.13 (s, 1 H), 7.03 (d, 1 H, J=2.3 Hz), 6.92 (d, 1 H, J=2.4 Hz), 6.88 (d, 2 H, J=8.7 Hz), 6.71 (d, 1 H, J=16.8 Hz); MS 276 (M−H)−.