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SYNTHETIC COMMUNICATIONSV
5
Preparation of graveoline (1)
To a stirred solution of 2-benzo[1,3]dioxol-5-yl-1H-quinolin-4-one (6) (100 mg,
0.37 mmol) in N,N-Dimethyl formamide (5 mL) at room temperature under a dry N2
atmosphere, potassium carbonate (156 mg, 1.1 mmol) and methyl iodide (80 mg,
0.56 mmol) were added at room temperature. The reaction mixture was heated and
stirred at 80 ꢀC for 5 h. After completion (monitored by TLC), the mixture was then
quenched with water and extracted with dichloromethane (3 ꢁ 15 mL). It was dried over
anhydrous Na2SO4 and after evaporation of the solvent under reduced pressure, the
crude product were purified by recrystallization from ethyl acetate to get Graveoline
100 mg (95%) as an off-white solid. mp.188.6–191.4 ꢀC; IR (KBr, cmꢂ1):1621, 1599,
1490, 1446, 1251, 1032, 751; Mass for C17H13NO3 [Mþ 1], found 280.3; 1 H NMR
(400 MHz, CDCl3) (d ppm): 3.60 (s, 3H), 5.99 (s, 1H), 6.14 (s, 2H), 7.02 (d, 1 H,
J ¼ 7.2 Hz), 7.08 (d, 1 H, J ¼ 8.0 Hz), 7.17 (s, 1H), 7.42–7.46 (m, 1H), 7.79 (d, 2 H,
J ¼ 3.6 Hz), 8.22 (d, 1 H, J ¼ 8.0 Hz).; 13 C NMR (100 MHz, CDCl3) (d ppm); 37.35,
101.72, 108.64, 109.00, 112.64, 116.04, 122.76, 123.68, 126.68, 126.81, 129.43, 132.37,
13
141.97, 147.94, 148.77, 154.44, 177.59. The obtained product 1 H and
matched with standard values.[16]
C values are
Preparation of graveolinine (2)
To a stirred solution of 2-benzo[1,3]dioxol-5-yl-1H-quinolin-4-one (6) (500 mg,
1.88 mmol) in N,N-Dimethyl formamide (20 mL) at room temperature under a dry N2
atmosphere, potassium carbonate (812 mg, 5.88 mmol) and methyl iodide (417 mg,
2.93 mmol) were added at room temperature. The reaction mixture was heated and
stirred at 80 ꢀC for 30 min. After completion (monitored by TLC), the mixture was then
quenched with water and extracted with dichloromethane (3 ꢁ 25 mL). The organic
layer was dried over anhydrous Na2SO4 and after evaporation of the solvent under
reduced pressure, the crude product was obtained. It was purified by column chroma-
tography to get graveolinine 400 mg (76%) as a white crystalline powder. mp.
113.8–116.5ꢀ C; IR (KBr, cmꢂ1): 1589, 1491, 1443, 1347, 1247, 1112, 1035, 766; Mass
for C17H13NO3 [M þ 1], found 280.3; H NMR (400 MHz, CDCl3) (d ppm): 4.11 (s, 3H),
1
6.04 (s, 2H), 6.94 (d, 1 H, J ¼ 8.0 Hz), 7.09 (s, 1H), 7.44–7.49 (t, 2 H, J ¼ 7.4 Hz),
7.59–7.62 (dd, 1 H, J1=1.6, J2=1.2 Hz), 7.68–7.70 (t, 2 H, J ¼ 10.3 Hz), 8.05 (d, 1 H,
J ¼ 8.4 Hz), 8.16 (d, 1 H, J ¼ 8.4 Hz); 13 C NMR (100 MHz, CDCl3) (d ppm); 55.60,
97.52, 101.37, 108.02, 108.38, 120.28, 121.61, 121.65, 125.19, 129.04, 129.96, 134.82,
148.28, 148.74, 149.09, 158.11, 162.76. The obtained product 1 H and 13 C values are
matched with standard values.[15]
Acknowledgments
The authors are grateful to Suven Life Sciences management for allowing them to publish
these results.