2296
D. K. KUMAR AND S. P. RAJENDRAN
DMSO-d6): d ¼ 3.79 (s, 3H, OCH3), 7.42 (d, 1H, J ¼ 8.2 Hz, C7H), 7.87 (d, 1H,
J ¼ 8.4 Hz, C3H), 7.90 (s, 1H, C5H), 8.15 (d, 1H, J ¼ 8.2 Hz, C8H), 8.25 (d, 1H,
C2H), 8.56 (s, 1H, C4H), 7.49–7.73 (m, 5H, ArH). Anal. calcd. for C19H14NO3Br:
C, 59.39; H, 3.67; N, 3.65. Found: C, 59.30; H, 3.87; N, 3.93.
3-(3-Benzoyl-oxiranyl)-1H-quinolin-2-one (4a–e)
A mixture of compound 2 (2c, 1.445 g, 0.005 mol) in methanol and potassium
carbonate and urea hydrogen peroxide (UHP) (2 to 3 mol extra) was stirred for 2 h.
After completion of the reaction, which was checked by TLC, the mixture was poured
into crushed ice. The precipitate was filtered off, dried, and column chromatographed
over silica gel using petroleum ether and ethyl acetate as eluent to give compound 4.
3-(3-Benzoyl-oxiranyl)-7-methyl-1H-quinolin-2-one (4c). Yield 79%; mp
1
205 ꢁC. IR (KBr): 1651, 1577 cmꢀ1. H NMR (400 MHz; DMSO-d6): d ¼ 2.34 (s,
3H, CH3), 4.11 (d, 1H, J ¼ 2.0 Hz, Hb), 4.73 (d, 1H, Ha), 7.51 (s, 1H, C8H), 7.80
(s, 1H, C4H), 7.23–8.10 (m, 7H, ArH), 11.93 (s, 1H, NH). 13C NMR (125 MHz;
DMSO-d6): d ¼ 20.3, 55.2, 58.8, 114.9, 118.5, 127.4, 127.5, 128.2, 128.9, 131.1,
131.9, 134.0, 135.1, 136.2, 161.0. HRMS (ESI) calcd. for C19H15NO3 (M þ Na)
328.0950, Found 328.0956.
3-(3-Benzoyl-oxiranyl)-1H-quinolin-2-one (4a). Yield 85%; mp 196 ꢁC. IR
(KBr): 1648, 1570 cmꢀ1
J ¼ 2.4 Hz, Hb), 4.75 (d, 1H, Ha), 7.82 (s, 1H, C4H), 7.13–8.12 (m, 9H, ArH),
12.01 (s, 1H, NH). Anal. calcd. for C18H13NO3: C, 74.22; H, 4.50; N, 4.81. Found:
C, 74.25; H, 4.43; N, 4.60.
.
1H NMR (500 MHz; DMSO-d6): d ¼ 4.10 (d, 1H,
3-(3-Benzoyl-oxiranyl)-6-methyl-1H-quinolin-2-one (4b). Yield 88%; mp
1
235 ꢁC. IR (KBr): 1645, 1567 cmꢀ1. H NMR (500 MHz; DMSO-d6): d ¼ 2.38 (s,
3H, CH3), 4.09 (d, 1H, J ¼ 2.5 Hz, Hb), 4.74 (d, 1H, Ha), 7.13 (s, 1H, C5H), 7.84
(s, 1H, C4H), 7.05–8.09 (m, 7H, ArH), 11.94 (s, 1H, NH). Anal. calcd. for
C19H15NO3: C, 74.74; H, 4.95; N, 4.59. Found: C, 74.84; H, 4.97; N, 4.48.
3-(3-Benzoyl-oxiranyl)-8-methyl-1H-quinolin-2-one (4d). Yield 83%; mp
1
217 ꢁC. IR (KBr): 1657, 1581 cmꢀ1. H NMR (500 MHz; DMSO-d6): d ¼ 2.89 (s,
3H, CH3), 4.13 (d, 1H, J ¼ 2.2 Hz, Hb), 4.72 (d, 1H, Ha), 7.85 (s, 1H, C4H),
7.18–8.18 (m, 8H, ArH), 11.93 (s, 1H, NH). Anal. calcd. for C19H15NO3: C,
74.74; H, 4.95; N, 4.59. Found: C, 74.76; H, 4.89; N, 4.65.
3-(3-Benzoyl-oxiranyl)-6-methoxy-1H-quinolin-2-one (4e). Yield 72%;
1
mp 247 ꢁC. IR (KBr): 1654, 1573 cmꢀ1. H NMR (500 MHz; DMSO-d6): d ¼ 3.80
(s, 3H, OCH3), 4.12 (d, 1H, J ¼ 2.3 Hz, Hb), 4.72 (d, 1H, Ha), 7.42 (s, 1H, C5H),
7.83 (s, 1H, C4H), 7.11–8.08 (m, 7H, ArH), 11.93 (s, 1H, NH). Anal. calcd. for
C19H15NO4: C, 71.02; H, 4.71; N, 4.36. Found: C, 69.95; H, 4.53; N, 4.39.
Furo[2,3-b]quinolin-2-yl-phenyl-methanone (5a–e)
From compound 3. A mixture of compound 3 (3c, 0.736 g, 0.002 mol) and
DBU (0.448 ml, 0.003 mol) was refluxed in 1,4-dioxane for 6 h. After completion