A. Guirado et al. / Tetrahedron 65 (2009) 5958–5963
5961
1H, J¼7.3 Hz), 7.17 (d, 2H, J¼8.1 Hz), 7.53 (d, 2H, J¼8.1 Hz); 13C NMR
(13), 91 (13), 77 (19); IR 3061, 2966, 2870, 2795, 1636, 1594, 1448,
1362, 1136, 1043, 930, 760, 695, 669 cmꢀ1
d
(CDCl3, 100.8 MHz) 21.45, 36.58, 68.09, 73.97, 126.06, 129.19,
.
129.38,139.55,151.92; MS m/z (%) 244 (Mþþ2,17), 242 (Mþ, 27),160
(30), 159 (100), 132 (13), 117 (16), 91 (25), 79 (14); IR (Nujol) 3279,
3.2.11. 3-(4-Chlorophenyl)-5-dichloromethyl-1-methyl-2-
pyrazoline (7c)
1636, 1515, 1227, 1066, 908, 817, 761, 740, 674 cmꢀ1
.
Yield 90%; column chromatography (silica gel–AcOEt–Hexane,
1:2) gave yellow powder; mp 72–73 ꢁC.(Found C, 47.66; H, 4.01; N,
10.05. C11H11Cl3N2 requires C, 47.60; H, 3.99; N, 10.09.) 1H NMR
3.2.6. 5-Dichloromethyl-3-(4-methoxyphenyl)-2-pyrazoline (6f)
Yield 95%; crystallization from ethanol gave yellow prisms; mp
107–109 ꢁC (dec).(Found C, 51.01; H, 4.76; N, 10.81. C11H12Cl2N2O
d
(CDCl3, 300 MHz) 3.04 (s, 3H), 3.25 (dd, 1H, J¼17.1, 10.8 Hz), 3.41
requires C, 50.98; H, 4.67; N, 10.81.) 1H NMR
d
(CDCl3, 300 MHz)
(dd, 1H, J¼17.1, 10.8 Hz), 3.83 (td, 1H, J¼10.8, 4.5 Hz), 5.86 (d, 1H,
3.08 (dd, 1H, J¼17.1, 7.2 Hz), 3.27 (dd, 1H, J¼17.1, 10.2 Hz), 3.82 (s,
3H), 4.30 (dt, 1H, J¼10.2, 7.2 Hz), 5.23 (br s, 1H), 5.62 (d, 1H,
J¼7.2 Hz), 6.90 (d, 2H, J¼9.0 Hz), 7.57 (d, 2H, J¼9.0 Hz); 13C NMR
J¼4.5 Hz), 7.32 (d, 2H, J¼11.4 Hz), 7.56 (d, 2H, J¼11.4 Hz); 13C NMR
d
(CDCl3, 75.4 MHz) 36.59, 42.91, 72.88, 74.74, 127.21, 128.81, 130.58,
134.88, 148.33; MS m/z (%) 280 (Mþþ4, 2), 278 (Mþþ2, 7), 276 (Mþ,
7), 195 (33), 193 (100), 158 (4), 128 (4), 75 (4); IR 3056, 2958, 2916,
2868, 2846, 2796, 1639, 1589, 1495, 1447, 1405, 1363, 1138, 1093,
d
(CDCl3, 75.4 MHz) 36.67, 55.39, 68.10, 74.05, 114.08, 124.77, 127.57,
151.55, 160.59; MS m/z (%) 260 (Mþþ2, 13), 258 (Mþ, 19), 223 (3),
187 (8), 175 (100), 160 (49), 132 (24), 115 (15), 77 (19); IR (Nujol)
3281, 1600, 1512, 1415, 1308, 1245, 1168, 1061, 1033, 906, 837, 757,
1037, 926, 829, 762 cmꢀ1
.
672 cmꢀ1
.
3.2.12. 5-Dichloromethyl-1-methyl-3-(4-methylphenyl)-2-
pyrazoline (7e)
3.2.7. 5-Dichloromethyl-3-(4-nitrophenyl)-2-pyrazoline (6g)
Yield 87%; crystallization from ethanol gave orange powder; mp
110–112 ꢁC.(Found C, 43.91; H, 3.40; N,15.16. C10H9Cl2N3O2 requires
Yield 86%; crystallization from MeOH–H2O gave yellow needles,
mp 72–73 ꢁC.(Found C, 55.89; H, 5.44; N, 10.78. C12H14Cl2N2 re-
quires C, 56.05; H, 5.49; N, 10.89.) 1H NMR
d (CDCl3, 400 MHz) 2.36
C, 43.82; H, 3.31; N, 15.33.) 1H NMR
d
(CDCl3, 300 MHz) 3.16 (dd, 1H,
(s, 3H), 3.02 (s, 3H), 3.25 (dd, 1H, J¼17.1, 10.6 Hz), 3.58 (dd, 1H,
J¼17.1, 7.3 Hz), 3.35 (dd, 1H, J¼17.1, 10.5 Hz), 4.45 (dtd, 1H, J¼10.5,
J¼17.1, 10.6 Hz), 3.77 (td, 1H, J¼10.6, 4.6 Hz), 5.84 (d, 1H, J¼4.6 Hz),
7.3, 2.4 Hz), 5.66 (d, 1H, J¼7.3 Hz), 6.40 (br s, 1H), 7.77 (d, 2H,
7.20 (d, 2H, J¼8.2 Hz), 7.53 (d, 2H, J¼8.2 Hz); 13C NMR
d (CDCl3,
J¼8.7 Hz), 8.23 (d, 2H, J¼8.7 Hz); 13C NMR
d
(CDCl3, 75.4 MHz)
100.8 MHz) 21.44, 37.02, 43.25, 73.17, 74.73, 126.02, 129.25, 129.31,
139.27, 149.80; MS m/z (%) 260 (Mþþ4, 15), 258 (Mþþ2, 71), 256
(Mþ, 81), 221 (9), 173 (100), 174 (43), 128 (10), 115 (8), 91 (13); IR
(Nujol) 2784, 1585, 1517, 1138, 1039, 935, 925, 870, 817, 753,
35.83, 68.48, 73.49,124.01,126.42,138.16,147.67,148.58; MS m/z (%)
277 (Mþþ4, 7), 275 (Mþþ2, 25), 273 (Mþ, 35), 238 (6),190 (100),191
(37), 144 (85), 117 (20), 76 (17); IR (Nujol) 3364, 1595, 1561, 1505,
1334, 1109, 1075, 851, 754, 692 cmꢀ1
.
713 cmꢀ1
.
3.2.8. 3-(4-Biphenylyl)-5-dichloromethyl-2-pyrazoline (6h)
Yield 80%; crystallization from ethanol gave yellow needles; mp
157 ꢁC.(Found C, 62.60; H, 4.69; N, 8.98. C16H14Cl2N2 requires C,
3.2.13. 5-Dichloromethyl-3-(4-methoxyphenyl)-1-methyl-2-
pyrazoline (7f)
Yield 83%; column chromatography (AcOEt–Hexane, 1:2) gave
yellow powder; mp 62–64 ꢁC.(Found C, 52.73; H, 5.22; N, 10.30.
62.97; H, 4.62; N, 9.21.) 1H NMR
d (CDCl3, 400 MHz) 3.14 (dd, 1H,
J¼17, 7.5 Hz), 3.33 (d, 1H, J¼17, 10.4 Hz), 4.34 (dt, 1H, J¼10.4, 7.5 Hz),
5.63 (d, 1H, J¼7.5 Hz), 6.13 (br s, 1H), 7.36 (t, 1H, J¼5.4 Hz), 7.44 (t,
2H, J¼7.2 Hz), 7.62–7.60 (m, 4H), 7.40 (d, 2H, J¼8.4 Hz); 13C NMR
C12H14Cl2N2O requires C, 52.76; H, 5.17; N, 10.26.) 1H NMR
d (CDCl3,
300 MHz) 3.01 (s, 3H), 3.24 (dd, 1H, J¼17.1, 10.8 Hz), 3.43 (dd, 1H,
J¼17.1,10.8 Hz), 3.76 (td, 1H, J¼10.8, 4.5 Hz), 3.83 (s, 3H), 5.85 (d,1H,
J¼4.5 Hz), 6.89 (d, 2H, J¼8.8 Hz), 7.58 (d, 2H, J¼8.8 Hz); 13C NMR
d
(CDCl3, 100.8 MHz) 36.47, 68.24, 73.95, 126.51, 127.06, 127.32,
127.72,128.93,130.95,140.36,141.97,151.18; MS m/z (%) 306 (Mþþ2,
15), 304 (Mþ, 23), 221 (100), 222 (32), 194 (8), 178 (9), 152 (20), 111
(11); IR (Nujol) 3297, 3258, 1641, 1412, 1342, 1219, 1065, 907, 843,
d (CDCl3, 75.4 MHz) 37.10, 43.41, 55.39, 73.19, 74.77, 114.01, 124.79,
127.57, 149.72,160.47; MS m/z (%) 274 (Mþþ2,14), 272 (Mþ, 22), 237
(4), 190 (31), 189 (100), 174 (42), 146 (14), 115 (9), 77 (6); IR 3045,
3003, 2957, 2916, 2837, 2794, 2039, 1608, 1515, 1455, 1363, 1308,
768, 754, 724, 696 cmꢀ1
.
1250, 1043, 922, 831, 762, 608 cmꢀ1
.
3.2.9. 5-Dichloromethyl-3-(2-naphthyl)-2-pyrazoline (6i)
Yield 86%; crystallization from ethanol gave yellow needles; mp
131–132 ꢁC.(Found C, 59.62; H, 4.32; N, 9.97. C14H12Cl2N2 requires C,
3.2.14. 5-Dichloromethyl-1-methyl-3-(4-nitrophenyl)-2-
pyrazoline (7g)
Yield 78%; crystallization from ethanol gave orange micro
needles; mp 117–118 ꢁC. (Found C, 45.79; H, 3.83; N, 14.59.
C11H11Cl2N3O2 requires C, 45.85; H, 3.85; N, 14.58.) 1H NMR
60.23; H, 4.33; N, 10.03.) 1H NMR
d
(CDCl3, 400 MHz) 3.22 (dd, 1H,
J¼16.9, 7.3 Hz), 3.40 (dd, 1H, J¼16.9, 10.4 Hz), 4.36 (dt, 1H, J¼10.4,
7.3 Hz), 5.65 (d, 1H, J¼7.3 Hz), 7.50–7.46 (m, 2H), 7.84–7.79 (m, 4H),
7.95 (dd, 1H, J¼8.7, 1.7 Hz); 13C NMR
d
(CDCl3, 100.8 MHz) 36.42,
d
(CDCl3, 300 MHz) 3.13 (s, 3H), 3.34 (dd, 1H, J¼17.4, 10.9 Hz), 3.46
68.30, 73.98, 123.27, 125.91, 126.64, 126.78, 127.87, 128.30, 128.43,
129.64, 133.15, 133.69, 151.56; MS m/z (%) 280 (Mþþ2, 7), 278 (Mþ,
53), 196 (50), 195 (100), 178 (20), 168 (25), 153 (22), 127 (40); IR
(Nujol) 3320, 3260, 1638, 1339, 1319, 1205, 1162, 1062, 860, 821,
(dd, 1H, J¼17.4, 10.9 Hz), 4.00 (td, 1H, J¼10.9, 4.2 Hz), 5.90 (d, 1H,
J¼4.2 Hz), 7.75 (d, 2H, J¼9 Hz), 8.22 (d, 2H, J¼9 Hz); 13C NMR
d
(CDCl3, 75.4 MHz) 36.03, 42.05, 72.44, 74.47, 124.01, 126.22,
138.29, 146.11, 147.46; MS m/z (%) 289 (Mþþ2, 12), 287 (Mþ, 18), 252
(6), 205 (36), 204 (100), 158 (84), 128 (11), 102 (8), 89 (7), 76 (10); IR
(Nujol) 1640, 1601, 1545, 1507, 1343, 1137, 1109, 1039, 941, 853, 763,
754 cmꢀ1
.
3.2.10. 5-Dichloromethyl-1-methyl-3-phenyl-2-pyrazoline (7a)
Yield 85%; column chromatography (silica gel–AcOEt–Hexane,
1:2) gave red oil; (Found C, 54.30; H, 5.01; N, 11.50. C11H12Cl2N2
753, 700 cmꢀ1
.
3.2.15. 3-(4-Biphenylyl)-5-dichloromethyl-1-methyl-2-
pyrazoline (7h)
requires C, 54.34; H, 4.97; N, 11.52.) 1H NMR
d (CDCl3, 300 MHz)
3.05 (s, 3H), 3.28 (dd, 1H, J¼17.1, 10.5 Hz), 3.46 (dd, 1H, J¼17.1,
Yield 80%; crystallization from ethanol–H2O gave pale yellow
prisms; mp 119–124 ꢁC (dec). (Found C, 60.76; H, 4.88; N, 8.64.
10.5 Hz), 3.82 (td, 1H, J¼10.5, 4.5 Hz), 5.86 (d, 1H, J¼4.5 Hz), 7.32–
7.40 (m, 3H), 7.63–7.66 (m, 2H); 13C NMR
d
(CDCl3, 75.4 MHz) 36.85,
C17H16Cl2N2 requires C, 63.96; H, 5.05; N, 8.78.) 1H NMR
d (CDCl3,
43.12, 73.07, 74.69, 126.03, 128.60, 129.14, 132.02, 149.60; MS m/z
(%) 244 (Mþþ2, 11), 242 (Mþ, 18), 207 (4), 160 (30), 159 (100), 117
300 MHz) 3.06 (s, 3H), 3.30 (dd, 1H, J¼17.2, 10.8 Hz), 3.48 (dd, 1H,
J¼17.2, 10.8 Hz), 3.83 (td, 1H, J¼10.8, 4.5 Hz), 5.86 (d, 1H, J¼4.5 Hz),