反应详情

Sodium hydride (31 mg, 0.78 mmol) was added to a solution of 4-(3,5-dichloropyridin-4-ylamino)-8-hydroxy-7-methoxy-2H-chromen-2-one (111 mg, 0.31 mmol, Example 29) and DMSO (2 mL) at rt under N2. After 5 min, 1,4-dibromobutane (0.05 mL, 0.42 mmol) was added. After 3 h, the reaction was poured into 1M KH2PO4 (30 mL) and extracted with ethyl acetate (40 mL×2). The combined extracts were dried, filtered, concentrated, and purified by silica gel chromatography (3:2→1:4; hexanes:ethyl acetate) to give 8-(4-bromobutoxy)-4-(3,5-dichloropyridin-4-ylamino)-7-methoxy-2H-chromen-2-one: 1H NMR (400 MHz, DMSO-d6): δ 9.51 (s, 1H), 8.81 (s, 2H), 7.95 (d, 1H), 7.21 (d, 1H), 4.64 (s, 1H), 4.01 (t, 2H), 3.92 (s, 3H), 3.63 (t, 2H), 2.05 (m, 2H), 1.80 (m, 2H); MS (ESI): 486.8.

1. waitAfter 3 h
2. extractionextracted with ethyl acetate (40 mL×2)
3. customThe combined extracts were dried
4. filtrationfiltered
5. concentrationconcentrated
6. custompurified by silica gel chromatography (3:2→1:4; hexanes:ethyl acetate)