反应详情

温度

110 °C

Phenyl 1′-methyl-2′-oxo-1′,2,2′,3-tetrahydrospiro[furo[2,3-g][1,4]-benzodioxine-8,3′-indole]-4′-carboxylate (0.30 g, 0.70 mmol), cyclobutylamine hydrochloride (0.23 g, 2.1 mmol), potassium carbonate (0.39 g, 2.8 mmol) and N,N-dimethylformamide (3.0 mL) were added to a microwave reaction vessel. The reaction was heated at 110° C. for 1 h in a microwave reactor, allowed to cool to ambient temperature, poured into water (25 mL) and extracted with ethyl acetate (3×50 mL). The combined organic extracts were washed with 1 M hydrochloric acid (50 mL) and brine (50 mL), dried over magnesium sulfate, filtered and concentrated in vacuo. The residue was purified by column chromatography and eluted with a 20% to 100% gradient of ethyl acetate in hexanes followed by recrystallization from dichloromethane/diethyl ether to afford N-cyclobutyl-1′-methyl-2′-oxo-1′,2,2′,3-tetrahydrospiro[furo[2,3-g][1,4]benzodioxine-8,3′-indole]-4′-carboxamide (0.045 g, 17%) as a colorless solid: mp 128-129° C. (dichloromethane/diethyl ether); 1H NMR (300 MHz, CDCl3) δ 7.41-7.33 (m, 1H), 7.26-7.21 (m, 1H), 6.97-6.93 (m, 1H), 6.51 (s, 1H), 6.20 (s, 1H), 5.46 (d, J=6.65 Hz, 1H), 4.96-4.81 (m, 2H), 4.35-4.01 (m, 5H), 3.25 (s, 3H), 2.27-2.09 (m, 2H), 1.70-1.40 (m, 4H); MS (ES+) m/z 407.0 (M+1). N,N,1′-trimethyl-2′-oxo-1,2,2′,3-tetrahydrospiro[furo[2,3-g][1,4]benzodioxine-8,3′-indole]-4′-carboxamide (0.12 g, 37%) was isolated as a byproduct from the synthesis of N-cyclobutyl-1′-methyl-2′-oxo-1′,2,2′,3-tetrahydrospiro[furo[2,3-g][1,4]benzodioxine-8,3′-indole]-4′-carboxamide, obtained as colorless solid: mp 218-221° C. (dichloromethane/diethyl ether); 1H NMR (300 MHz, CDCl3) 7.32 (dd, J=7.8, 7.8 Hz, 1H), 6.91-6.84 (m, 2H), 6.44 (s, 1H), 6.22 (s, 1H), 5.05 (d, J=8.8 Hz, 1H), 4.79 (d, J=8.8 Hz, 1H), 4.20-4.04 (m, 4H), 3.28 (s, 3H), 2.79 (s, 3H), 2.19 (s, 3H); MS (ES+) m/z 381.0 (M+1).

1. temperatureto cool to ambient temperature
2. extractionextracted with ethyl acetate (3×50 mL)
3. washThe combined organic extracts were washed with 1 M hydrochloric acid (50 mL) and brine (50 mL)
4. dry with materialdried over magnesium sulfate
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customThe residue was purified by column chromatography
8. washeluted with a 20% to 100% gradient of ethyl acetate in hexanes
9. customfollowed by recrystallization from dichloromethane/diethyl ether