反应详情

Add a solution of 2,3-dibromo-benzo[b]thiophen-6-ol (43.9 g, 143 mmol) in DMF (1000 mL), dropwise, to a suspension of sodium hydride in DMF (1.5 L) at 0° C. Stir for 20 minutes, add benzyl bromide (17 mL, 143 mmol). Remove ice bath, and stir at room temperature for 2 hours. Pour reaction mixture into water (8 L) and ethyl acetate (4 L) and stir overnight. Separate layers and wash organic layer with water (3×800 mL) and brine (800 mL). Dry with sodium sulfate, filter, and concentrate in vacuo to give 52.4 g of 6-benzyloxy-2,3-dibromo-benzo[b]thiophene (92%).

1. stirringRemove ice bath, and stir at room temperature for 2 hours
2. additionPour
3. stirringstir overnight
4. washSeparate layers and wash organic layer with water (3×800 mL) and brine (800 mL)
5. dry with materialDry with sodium sulfate
6. filtrationfilter
7. concentrationconcentrate in vacuo