反应详情

Potassium t-butoxide (35 mg, 0.3 mmol) was added to a solution of 4-chloro-8-(cyclopentyloxy)-7-methoxy-2H-chromen-2-one (29 mg, 0.1 mmol, Example 7, Step 1), 2,6-dichloro-3-methylaniline (26 mg, 0.15 mmol), and DMSO (1 mL). After 14 h, the reaction was poured into 1M KH2PO4 (20 mL), and extracted with ethyl acetate (20 mL×2). The combined extracts were dried, filtered, concentrated, and purified by silica gel chromatography (4:1→0:1; hexanes:ethyl acetate) to give 8-(cyclopentyloxy)-4-(2,6-dichloro-3-methylphenylamino)-7-methoxy-2H-chromen-2-one: 1H NMR (400 MHz, DMSO-d6): δ 9.38 (s, 1H), 7.95 (d, 1H), 7.58 (d, 1H), 7.48 (d, 1H), 7.18 (d, 1H), 4.82 (m, 1H), 4.33 (s, 1H), 3.90 (s, 3H), 2.40 (s, 3H), 1.90-1.45 (m, 8H); MS (ESI): 433.9.

1. extractionextracted with ethyl acetate (20 mL×2)
2. customThe combined extracts were dried
3. filtrationfiltered
4. concentrationconcentrated
5. custompurified by silica gel chromatography (4:1→0:1; hexanes:ethyl acetate)