M.L.N. Rao, A. Kumar / Tetrahedron 70 (2014) 6995e7005
7003
161.02, 160.78, 156.30, 151.47, 134.77, 130.03, 128.79, 127.85, 127.61,
127.13, 123.83, 123.40, 122.76, 122.44, 114.32, 114.00, 55.45; ESI (HRMS)
(m/z) calcd for C20H15O3 [MþH]þ 303.1021, found: 303.1025.
139.76, 127.86, 127.33, 127.09, 112.68, 103.55, 95.76, 93.55, 55.75,
55.37; ESI (HRMS) (m/z) calcd for C17H15O4 [MþH]þ 283.0970,
found: 283.0972.
4.3.17. 4-(4-Fluorophenyl)-2H-benzo[h]chromen-2-one (3.22). White
solid (0.135 g, 62%); mp 168e170 ꢀC, Rf (20% ethyl acetate in hexane)
0.48; IR (neat, cmꢁ1): 3064, 1720, 1508, 1465, 1231, 1154, 1094, 845,
816; dH NMR (500 MHz, CDCl3): 8.63e8.61 (m, 1H, AreH), 7.88e7.86
(m,1H, AreH), 7.68e7.62 (m, 3H, AreH), 7.50e7.48 (m, 2H, AreH), 7.43
(d, J¼8.9 Hz, 1H, AreH), 7.27e7.24 (m, 2H, AreH), 6.44 (s, 1H); dC NMR
(125 MHz, CDCl3): 163.46 (d, JCeF¼248.36 Hz), 160.66, 155.54, 151.45,
134.80, 131.54, 130.44 (d, JCeF¼8.4 Hz), 128.95, 127.65, 127.26, 124.07,
123.28, 122.71, 122.00, 116.08 (d, JCeF¼21.6 Hz), 114.61, 114.01; ESI
(HRMS) (m/z) calcd for C19H12FO2 [MþH]þ 291.0821, found: 291.0823.
4.3.23. 5,7-Dimethoxy-4-(4-methoxyphenyl)-2H-chromen-2-one11
(3.28). White solid (0.192 g, 82%); mp 152e154 ꢀC, Rf (30% ethyl ac-
etate in hexane) 0.37; IR (neat, cmꢁ1): 3075, 2945, 2831, 1714, 1624,
1590, 1509, 1462, 1352, 1227, 1161, 1107, 1027, 839; dH NMR (500 MHz,
CDCl3): 7.21 (d, J¼8.85 Hz, 2H, AreH), 6.90 (d, J¼8.85 Hz, 2H, AreH),
6.52 (d, J¼2.4 Hz, 1H, AreH), 6.24 (d, J¼2.45 Hz, 1H, AreH), 5.99 (s,
1H), 3.867 (s, 3H), 3.863 (s, 3H), 3.47 (s, 3H); dC NMR (125 MHz,
CDCl3): 163.22, 160.95, 159.53, 158.27, 157.24, 155.43, 132.07, 128.68,
112.70, 112.60, 103.63, 95.78, 93.55, 55.73, 55.44, 55.28; ESI (HRMS)
(m/z) calcd for C18H17O5 [MþH]þ 313.1076, found: 313.1075.
4.3.18. 4-p-Tolyl-2H-benzo[h]chromen-2-one (3.23). White solid
(0.170 g, 79%); mp 138e140 ꢀC, Rf (20% ethyl acetate in hexane) 0.51;
IR (neat, cmꢁ1): 3048, 1722, 1366, 824, 755; dH NMR (500 MHz,
CDCl3): 8.63e8.61 (m, 1H, AreH), 7.86e7.84 (m, 1H, AreH), 7.67e7.64
(m, 2H, AreH), 7.61 (d, J¼9.0 Hz, 1H, AreH), 7.51 (d, J¼9.0 Hz, 1H,
AreH), 7.40 (d, J¼8.0 Hz, 2H, AreH), 7.35 (d, J¼8.05 Hz, 2H, AreH),
6.45 (s, 1H), 2.47 (s, 3H); dC NMR (125 MHz, CDCl3): 160.96, 156.67,
151.39, 139.81, 134.74, 132.66, 129.53, 128.78, 128.44, 127.60, 127.10,
123.84, 123.31, 122.70, 122.43, 114.27, 114.22, 21.36; ESI (HRMS) (m/z)
calcd for C20H15O2 [MþH]þ 287.1072, found: 287.1076.
4.3.24. 4-(4-(Benzyloxy)phenyl)-5,7-dimethoxy-2H-chromen-2-one
(3.29). White solid (0.216 g, 74%); mp 164e166 ꢀC, Rf (30% ethyl ac-
etate in hexane) 0.48; IR (neat, cmꢁ1): 3056, 3029, 2980, 1733, 1608,
1595, 1510, 1351, 1239, 1154, 1110, 1046, 1010, 946, 824, 751; dH NMR
(500 MHz, CDCl3): 7.46 (d, J¼7.05 Hz, 2H, AreH), 7.42e7.39 (m, 2H,
AreH), 7.36e7.34 (m, 1H, AreH), 7.21 (d, J¼8.85 Hz, 2H, AreH), 6.97
(d, J¼8.85 Hz, 2H, AreH), 6.52 (d, J¼2.40 Hz, 1H, AreH), 6.24 (d,
J¼2.40 Hz, 1H, AreH), 5.99 (s, 1H), 5.12 (s, 2H), 3.86 (s, 3H), 3.46 (s,
3H); dC NMR (125 MHz, CDCl3): 163.21, 160.96, 158.68, 158.23, 157.22,
155.38, 136.73, 132.31, 128.69, 128.61, 128.05, 127.52, 113.67, 112.57,
103.60, 95.77, 93.52, 70.03, 55.73, 55.40; ESI (HRMS) (m/z) calcd for
4.3.19. 4-(4-Ethoxyphenyl)-2H-benzo[h]chromen-2-one (3.24). Pale
yellow solid (0.185 g, 78%); mp 128e130 ꢀC, Rf (20% ethyl acetate in
hexane) 0.46; IR (neat, cmꢁ1): 3045, 2980, 1733, 1611, 1514, 1369,
1259, 1175, 1044, 815, 748; dH NMR (500 MHz, CDCl3): 8.64e8.62 (m,
1H, AreH), 7.87e7.85 (m, 1H, AreH), 7.66e7.62 (m, 3H, AreH), 7.56
(d, J¼8.6 Hz,1H, AreH), 7.44 (d, J¼8.6 Hz, 2H, AreH), 7.05 (d, J¼8.9 Hz,
2H, AreH), 6.44 (s, 1H), 4.13 (q, J¼6.87 Hz, 2H), 1.48 (t, J¼7.0 Hz, 3H);
dC NMR (125 MHz, CDCl3): 161.06, 160.16, 156.35, 151.39, 134.73,
130.02, 128.77, 127.60, 127.10, 123.81, 123.36, 122.74, 122.46, 114.76,
114.33, 113.90, 63.67, 14.78; EI (HRMS) (m/z) calcd for C21H16O3 [M]þ
316.1099, found: 316.1094.
C
24H21O5 [MþH]þ 389.1389, found: 389.1384.
4.3.25. 4-(Benzo[d][1,3]dioxol-5-yl)-5,7-dimethoxy-2H-chromen-2-
one12b (3.30). Pale yellow solid (0.196 g, 80%); mp 192e194 ꢀC, Rf (30%
ethyl acetate in hexane) 0.42; IR (neat, cmꢁ1): 3089, 2923, 2854, 1709,
1609, 1592, 1502, 1380, 1351, 1220, 1159, 1112, 1034, 907, 850, 819; dH
NMR (500 MHz, CDCl3): 6.81 (d, J¼8.55 Hz, 1H, AreH), 6.75e6.74 (m,
2H, AreH), 6.51 (d, J¼2.45 Hz, 1H, AreH), 6.24 (d, J¼2.45 Hz, 1H,
AreH), 6.01 (s, 2H), 5.98 (s, 1H), 3.86 (s, 3H), 3.51 (s, 3H); dC NMR
(125 MHz, CDCl3): 163.29, 160.86, 158.15, 157.17, 155.19, 147.41, 146.77,
133.54, 120.82, 112.68, 108.25, 107.47, 103.52, 101.16, 95.80, 93.52,
55.74, 55.58; ESI (HRMS) (m/z) calcd for C18H15O6 [MþH]þ 327.0863,
found: 327.0869.
4.3.20. 6-Methyl-5-nitro-4-p-tolyl-2H-chromen-2-one (3.25). Yellow
solid (0.166 g, 75%); mp 148e150 ꢀC, Rf (20% ethyl acetate in hexane)
0.42; IR (neat, cmꢁ1): 3035, 2921, 1734, 1536, 1348, 818; dH NMR
(500 MHz, CDCl3): 7.49e7.46 (m, 2H, AreH), 7.20 (d, J¼7.7 Hz, 2H,
AreH), 7.16 (d, J¼8.3 Hz, 2H, AreH), 6.36 (s, 1H), 2.41 (s, 3H), 2.28 (s,
3H); dC NMR (125 MHz, CDCl3): 158.75, 152.67, 152.55, 147.78, 139.98,
134.11,131.54,128.89,127.13,126.94,119.72,119.47,111.46, 21.42,17.60;
ESI (HRMS) (m/z) calcd for C17H14NO4 [MþH]þ 296.0923, found:
296.0927.
4.3.26. 6-Chloro-4-phenyl-2H-chromen-2-one6e (4.1). White solid
(0.149 g, 77%); mp 150e152 ꢀC, Rf (20% ethyl acetate in hexane) 0.60;
IR (neat, cmꢁ1): 3049, 1722, 1555, 1409, 1353, 1178, 950, 939, 700; dH
NMR (500 MHz, CDCl3): 7.56e7.54 (m, 3H, AreH), 7.50 (dd, J¼2.42,
8.55 Hz, 1H, AreH), 7.45e7.42 (m, 3H, AreH), 7.36 (d, J¼8.55 Hz, 1H,
AreH), 6.41 (s,1H); dC NMR (125 MHz, CDCl3): 160.04, 154.60, 152.54,
134.46, 131.87, 129.98, 129.62, 129.08, 128.27, 126.31, 120.12, 118.73,
116.08; ESI (HRMS) (m/z) calcd for C15H10ClO2 [MþH]þ 257.0369,
found: 257.0368.
4.3.21. 4-(4-Ethoxyphenyl)-6-methyl-5-nitro-2H-chromen-2-one
(3.26). Yellow solid (0.178 g, 73%); mp 120e122 ꢀC, Rf (20% ethyl
acetate in hexane) 0.34; IR (neat, cmꢁ1): 3061, 2976, 1735, 1607, 1532,
1509, 1245, 1182, 1044, 817; dH NMR (500 MHz, CDCl3): 7.49e7.45 (m,
2H, AreH), 7.18 (d, J¼8.85 Hz, 2H, AreH), 6.88 (d, J¼8.55 Hz, 2H,
AreH), 6.35 (s, 1H), 4.08 (q, J¼7.02 Hz, 2H), 2.28 (s, 3H), 1.44 (t,
J¼7.02 Hz, 3H); dC NMR (125 MHz, CDCl3): 160.17, 158.83, 152.69,
152.35, 147.91, 134.06, 128.64, 126.91, 126.59, 119.48, 119.42, 114.10,
111.67, 63.53, 17.60, 14.71; ESI (HRMS) (m/z) calcd for C18H16NO5
[MþH]þ 326.1028, found: 326.1021.
4.3.27. 6-Chloro-4-p-tolyl-2H-chromen-2-one6a (4.2). White solid
(0.173 g, 85%); mp 188e190 ꢀC, Rf (20% ethyl acetate in hexane) 0.60;
IR (neat, cmꢁ1): 3068, 2919, 1733, 1610, 1552, 1415, 1353, 1247, 1183,
1122, 935, 816, 536; dH NMR (500 MHz, CDCl3): 7.50e7.48 (m, 2H,
AreH), 7.36e7.32 (m, 5H, AreH), 6.39 (s, 1H), 2.46 (s, 3H); dC NMR
(125 MHz, CDCl3): 160.21, 154.70, 152.56, 140.28, 131.77, 131.58, 129.76,
129.57, 128.24, 126.39, 120.24, 118.71, 115.75, 21.37; ESI (HRMS) (m/z)
calcd for C16H12ClO2 [MþH]þ 271.0526, found: 271.0529.
4.3.22. 5,7-Dimethoxy-4-phenyl-2H-chromen-2-one17 (3.27). White
solid (0.154 g, 71%); mp 160e162 ꢀC, Rf (30% ethyl acetate in hexane)
0.51; IR (neat, cmꢁ1): 3055, 2938, 1711, 1610, 1595, 1353, 1227,
1160, 1111, 821, 781; dH NMR (500 MHz, CDCl3): 7.37e7.36 (m,
3H, AreH), 7.26e7.24 (m, 2H, AreH), 6.52 (d, J¼2.4 Hz, 1H, AreH),
6.22 (d, J¼2.45 Hz, 1H, AreH), 6.00 (s, 1H), 3.86 (s, 3H), 3.41 (s, 3H);
dC NMR (125 MHz, CDCl3): 163.34, 160.84, 158.21, 157.16, 155.65,
4.3.28. 6-Chloro-4-(4-ethoxyphenyl)-2H-chromen-2-one (4.3). White
solid (0.169 g, 75%); mp 168e170 ꢀC, Rf (20% ethyl acetate in hexane)
0.50; IR (neat, cmꢁ1): 3047, 2977, 1731, 1609, 1515, 1308, 1292, 1183,
1153, 951, 820; dH NMR (500 MHz, CDCl3): 7.52 (d, J¼2.45 Hz, 1H,
AreH), 7.49 (dd, J¼2.45, 8.85 Hz, 1H, AreH), 7.38e7.33 (m, 3H, AreH),
7.04 (d, J¼8.55 Hz, 2H, AreH), 6.37 (s, 1H), 4.12 (q, J¼6.85 Hz, 2H),1.47
(t, J¼6.87 Hz, 3H); dC NMR (125 MHz, CDCl3): 160.45, 160.26, 154.35,