[I:1][C:2]1[CH:3]=[C:4]([O:10][CH3:11])[C:5]([O:8][CH3:9])=[CH:6][CH:7]=1.[Br:12]Br.S(=O)(O)[O-].[Na+]>C(O)(=O)C.O>[Br:12][C:7]1[CH:6]=[C:5]([O:8][CH3:9])[C:4]([O:10][CH3:11])=[CH:3][C:2]=1[I:1]4-Iodoveratrole (26.0 g, 0.0985M) in acetic acid (25 ml) was treated with bromine (6.5 ml, 0.127M) in acetic acid (30 ml) and stirred at room temperature for one hour. The mixture was diluted with water (300 ml) and treated with sodium bisulfite to discharge the excess bromine. The white solid was filtered, washed with water and dried in vacuo over P2O5 to give 4-bromo-5-iodoveratrole (33.0 g, 95% yield) as a white solid, mp 98°-100° C. (literature: Baker et al., J. Chem. Soc. 3986 (1961), mp 102°-104° C.). NMR (CDCl3) δ 3.83 ppm (s, 6H, (2x) OCH3), 7.06 (s, 1H, ArH), 7.21 (s, 1H, ArH).
Wird geladen…
