反应详情

2-(3,5-Dichloro-pyridin-4-yl)-1-(2,3,4-trimethoxy-phenyl)-ethanone from preparation 2 (20 g, 56 mmol) was dissolved in DCM (75 mL) under argon. BCl3 (95 mL of a 1M solution in DCM) was added slowly at room temperature for 2 hours. Water (50 mL) was added slowly followed by EtOH (200 mL). The white precipitate was filtered and re-crystallised from EtOH. 2-(3,5-Dichloro-pyridin-4-yl)-1-(2-hydroxy-3,4-dimethoxy-phenyl)-ethanone was obtained as a white solid. 1H NMR (CDCl3) δ=11.92 (1H, s), 8.54 (2H, s), 7.68 (1H, d), 6.60 (1H, d), 4.67 (2H, s), 3.98 (3H, s), 3.90 (3H, s). Yield 14.2 g (74%)

1. filtrationThe white precipitate was filtered
2. customre-crystallised from EtOH