Molecules 2011, 16
929
8-Methoxy-3-methyl-1-phenyl-1H-chromeno[4,3-c]pyrazol-4-one (2e). Obtained as described for 2a
starting from 1e (0.500 g, 1.61 mmol) to obtain 2e (0.258 g, 0.84 mmol, 52% yield) as a white powder,
1
mp = 232–234 °C, IR νneat (cm−1): 1734 (OC=O), 1238, 1203 (C-O). H-NMR δ: 7.32 (d, 1H, H-6,
3J = 9.0), 6.98 (dd, 1H, H-7, 3J = 9.0, 4J = 3.1), 6.50 (d, 1H, H-9, 4J = 3.1), 7.63-7.54 (m, 5H, Ph), 2.68
13
(s, 3H, CH3). C-NMR δ: 158.4 (C-4), 155.6 (C-8), 151.0 (C-3), 147.9 (C-5a), 141.9 (C-9b), 139.5
(Ci), 130.5 (Co), 130.5 (Cp), 127.4 (Cm), 119.2 (C-7), 118.8 (C-6), 112.1 (C-9a), 106.7 (C-3a), 105.5
(C-9), 13.4 (Me). m/z = 306.1 (M, 100%), 291.3 (28%), 277 (3%), 77 (22%). Anal. Calcd. for
C18H14N2O3; C, 70.58; H, 4.61; N, 9.14. Found: C, 70.22; H, 4.50; N, 9.00.
6-Methoxy-3-methyl-1-phenyl-1H-chromeno[4,3-c]pyrazol-4-one (2f). Obtained as described for 2a
starting from 1f (0.500 g, 1.61 mmol) to give 2f (0.248 g, 0.806 mmol, 50% yield) as a white powder,
1
mp = 238–240 °C, IR νneat (cm−1): 1743 (OC=O), 1273, 1207 (C-O). H-NMR δ: 7.02 (dd, 1H, H-7,
3J = 8.2, 7.6), 6.97 (t, 1H, H-8, 3J = 7.6, 8.2), 6.65 (dd, 1H, H-9 3J = 7.6, 4J = 1.5), 7.54–7.62 (m, 5H,
Ph), 2.69 (s, 3H, CH3). 13C-NMR δ: 157.6 (C-4), 151.0 (C-3), 148.4 (C-6), 143.3 (C-5a), 142.1 (C-9b),
139.6 (Ci), 130.4 (Cp), 130.0 (Co), 127.2 (Cm), 123.9 (C-8), 114.1 (C-9), 112.9 (C-7), 112.7 (C-9a),
106.6 (C-3a), 13.2 (Me). m/z = 306.1 (M, 100%), 291.3 (5%), 277 (20%), 77 (22%). Anal. Calcd. for
C18H14N2O3; C, 70.58; H, 4.61; N, 9.14. Found: C, 70.83; H, 4.70; N, 9.00.
8-Bromo-3-methyl-6-methoxy-1H-chromeno[4,3-c]pyrazol-4-one (2g). Obtained as described for 2a
starting from 1g (0.500 g, 1.28 mmol) to obtain 2g (0.393 g, 1.01 mmol, 79% yield) as a pale yellow
powder, mp = 289–292 °C, IR νneat (cm−1): 1744 (OC=O), 1275, 1205 (C-O). 1H-NMR δ: 6.72 (s, 1H,
H-9), 7.06 (s, 1H, H-6), 7.51-7.62 (m, 5H, Ph), 2.67 (s, 3H, CH3). 13C-NMR δ: 156.7 (C-4), 151.1 (C-5a),
148.9 (C-3), 142.3 (C-6), 140.1 (C-9b), 139.0 (C-10), 130.7 (C-9), 130.1 (C-11), 127.0 (C-12), 123.9
(C-5), 123.3 (C-8), 116.5 (C-13), 116.1 (C-7), 113.7 (C-9a), 106.8 (C-3a), 13.1 (Me). m/z = 384.5 (M,
80%), 386.2 (100%), 385.5 (25%), 357.5 (10%), 290.5 (10%), 77.0 (25%). Anal. Calcd. for
C18H13N2O3Br; C, 56.13; H, 3.40; N, 7.27. Found: C, 55.88; H, 3.40; N, 7.20.
6-Bromo-8-Chloro-3-methyl-1H-chromeno[4,3-c]pyrazol-4-one (2h). Obtained as described for 2a
starting from 1h (0.5 g, 1.27 mmol) to obtain 2h (0.249 g, 0.64 mmol, 50% yield) as a pale yellow
powder, mp = 259–261 °C, IR νneat (cm−1): 1749 (OC=O), 1277, 1224 (C-O). 1H-NMR δ: 6.90 (s, 1H,
H-9), 7.82 (s, 1H, H-7), 7.53-7.65 (m, 5H, Ph), 2.65 (s, 3H, CH3). 13C-NMR δ: 156.2 (C-4), 151.1 (C-
5a), 148.2 (C-3), 140.2 (C-9b), 138.8 (C-10), 134.2 (C-7), 130.9 (C-9), 130.6 (C-11), 129.5 (C-8),
126.9 (C-12), 121.4 (C-13), 113.9 (C-6), 112.6 (C-9a), 106.8 (C-3a), 13.0 (Me). m/z = 390.0 (M,
100%), 389.5 (60%), 388.5 (62%), 310 (5%), 77(25%). Anal. Calcd. for C17H10N2O2BrCl; C, 52.40; H,
2.59; N, 7.19. Found: C, 52.70; H, 2.63; N, 7.00.
6,8-Dichloro-3-methyl-1H-chromeno[4,3-c]pyrazol-4-one (2i). Obtained as described for 2a starting from
1i (0.5 g, 1.43 mmol) to obtain 2i (0.259 g, 0.74 mmol, 52% yield) as a pale yellow powder,
mp = 224–226 °C, IR νneat (cm−1): 1750 (OC=O), 1225 (C-O). 1H-NMR δ: 6.90 (s, 1H, H-9), 7.47 (s, 1H,
H-7), 7.52-7.64 (m, 5H, Ph), 2.65 (s, 3H, CH3). 13C-NMR δ: 156.2 (C-4), 151.1 (C-5a), 147.8 (C-3), 140.2
(C-9b), 138.8 (C-10), 131.3 (C-7), 130.9 (C-9), 130.3 (C-11), 129.1 (C-8), 126.9 (C-12), 124.1 (C-6), 120.8
(C-13), 114.0 (C-9a), 106.8 (C-3a), 13.0 (Me). m/z = 344.5 (M, 100%), 346.2 (80%), 345.3 (68%), 308.5,
77 (22%). Anal. Calcd. for C17H10N2O2Cl2; C, 59.15; H, 2.92; N, 8.11. Found: C, 58.90; H, 2.89; N, 8.00.