反应详情

温度

90 °C

Acetamide (6.07 g, 0.103 mol) and dimethylformamide dimethyl acetal (20 ml, 0.15 mol) were stirred at 80° C. in dioxane (20 ml) for 2 hours. The reaction mixture was concentrated in vacuo, ether (50 ml) added, the solution refridgerated for 30 minutes then triturated to give an orange solid. The solid was collected under suction and the fitrate concentrated in vacuo to a red oil (4.63 g). A portion of this oil (1.20 g) was added to a solution of 3-bromo-4-methoxyphenylhydrazine (Desc. 14; 2.12 g, 9.77 mmol) in acetic acid (20 ml) and the mixture stirred at 90° C. for 2 hours. The reaction mixture was concentrated, treated with saturated sodium hydrogen carbonate (150 ml) and extracted with dichloromethane (2×50 ml). The combined extracts were dried (MgSO4), evaporated and the residue purified by flash chromatography, eluting with 1:1 then 3:1 ethyl acetate/hexane then ethyl acetate, to give the title compound (0.33 g, 13%); δH (250MHz, CDCl3) 2.51 (3H, s, 5'--CH3), 3.97 (3H, s, ArOCH3), 7.00 (1H, d J 8.7Hz, 6-H), 7.37 (1H, dd, J8.7, 2.6Hz, 5-H), 7.67 (1H, d, J 2.6Hz, 3-H), 7.92 (1H, s, 3'-H).

1. concentrationThe reaction mixture was concentrated in vacuo, ether (50 ml)
2. additionadded
3. customthen triturated
4. customto give an orange solid
5. customThe solid was collected under suction
6. concentrationthe fitrate concentrated in vacuo to a red oil (4.63 g)
7. concentrationThe reaction mixture was concentrated
8. additiontreated with saturated sodium hydrogen carbonate (150 ml)
9. extractionextracted with dichloromethane (2×50 ml)
10. dry with materialThe combined extracts were dried (MgSO4)
11. customevaporated
12. customthe residue purified by flash chromatography
13. washeluting with 1:1