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HETEROCYCLES, Vol. 81, No. 6, 2010
4-(2-Tolyl)-1H-1-tritylpyrazole (1d): Colorless crystals; mp 100103 °C; IR (KBr) max 1602 (C=C),
1563 (C=C) cm1; 1H-NMR (300 MHz, CDCl3): δ 7.81 (1H, d, J = 0.7 Hz, pyrazole-H), 7.46 (1H, d, J =
0.7 Hz, pyrazole-H), 7.34–7.28 (10H, m, Tr-H, Tol-H), 7.25–7.1 (9H, m, Tr-H, Tol-H), 2.38 (3H, brs,
CH3); 13C-NMR (75 MHz, CDCl3): δ 143.2, 139.2, 135.2, 132.2, 131.3, 130.6, 130.2, 129.0, 127.9, 127.7,
126.7, 125.9, 120.7, 78.6, 21.2; MS (EI) m/z 400 (M+), 243 (100%); HRMS m/z calcd for C29H24N2 (M+)
400.1940, found 400.1934.
4-(3-Nitrophenyl)-1H-1-tritylpyrazole (1e): Colorless crystals; mp 202204 °C; IR (KBr) max 1570
(C=C), 1528 (ArNO2) cm1; 1H-NMR (300 MHz, CDCl3): δ 8.24 (1H, t, J = 2.2 Hz, 2’-H), 8.04 (1H, ddd,
J = 8.0, 2.4, 1.1 Hz, 3’- or 6’-H), 8.00 (1H, d, J = 0.6 Hz, pyrazole-H), 7.75 (1H, br d, J = 8.0 Hz, 3’- or
6’-H), 7.74 (1H, d, J = 0.6 Hz, pyrazole-H), 7.49 (1H, t, J = 8.0 Hz, 2’-H), 7.38–7.32 (10H, m, Tr-H),
7.24–7.14 (5H, m, Tr-H); 13C-NMR (75 MHz, CDCl3): δ 148.7, 142.7, 137.3, 134.5, 131.3, 130.1, 129.7,
129.6, 128.0, 127.9, 120.9, 120.1, 119.6, 79.2; MS (EI) m/z 431 (M+), 243 (100%); HRMS m/z calcd for
C28H21N3O2 (M+) 431.1634, found 431.1638.
4-(3-Aminophenyl)-1H-1-tritylpyrazole (1f): Colorless crystals; mp 155157 °C; IR (KBr) max 3380
1
(N-H), 1617 (C=C), 1588 (C=C) cm1; H-NMR (300 MHz, CDCl3): δ 7.89 (1H, d, J = 0.7 Hz,
pyrazole-H), 7.57 (1H, d, J = 0.7 Hz, pyrazole-H), 7.38–7.31 (9H, m, Tr-H), 7.27–7.19 (6H, m, Tr-H),
7.09 (1H, t, J = 7.7 Hz, Ar-5H), 6.82 (1H,br d, J = 7.7, Hz, Ar-4H), 6.74 (1H,br s, Ar-2H), 6.52 (1H,dd, J
13
= 7.7, 2.4 Hz, Ar-6H), 3.64 (2H, brs, -NH2); C-NMR (75 MHz, CDCl3): δ 146.8, 143.1, 137.3, 133.5,
130.2, 129.7, 129.2, 127.8, 121.7, 116.0, 113.3, 112.1; MS (EI) m/z 401 (M+), 243 (100%); HRMS m/z
calcd for C28H23N3 (M+) 401.1892, found 401.1885.
1
4-(Thiophen-2-yl)-1H-1-tritylpyrazole10 (1g): H-NMR (200 MHz, CDCl3): δ 7.84 (1H, d, J = 0.8 Hz,
pyrazole-H), 7.55 (1H, d, J = 0.8 Hz, pyrazole-H), 7.33–7.28 (9H, m, Tr-H), 7.23–7.15 (6H, m, Tr-H),
7.08 (1H, dd, J = 5.0, 1.3 Hz, thienyl-5H), 6.99 (1H, dd, J = 3.6, 1.3 Hz, thienyl-3H), 6.94 (1H, dd, J =
5.0, 3.6 Hz, thienyl-4H).
4-(Thiophen-3-yl)-1H-1-tritylpyrazole (1h): Colorless crystals; mp 203205 °C; IR (KBr) max 1595
(C=C) cm1; 1H-NMR (300 MHz, CDCl3): δ 7.88 (1H, d, J = 0.7 Hz, pyrazole-H), 7.56 (1H, d, J = 0.7 Hz,
pyrazole-H), 7.36–7.12 (9H, m, Ar-H); 13C-NMR (75 MHz, CDCl3): δ 143.1, 137.5, 130.1, 129.1, 127.9,
127.8, 127.8, 127.2, 126.1, 126.0, 118.2, 78.7; MS (EI) m/z 392 (M+), 243 (100%); HRMS m/z calcd for
C26H20N2S (M+) 392.1347, found 392.1345.
4-(Fur-2-yl)-1H-1-tritylpyrazole (1i): Colorless crystals; mp 114118 °C; IR (KBr) max 1610 (C=C),
1
1598 (C=C) cm1; H-NMR (200 MHz, CDCl3): δ 7.87 (1H, s, pyrazole-H), 7.61 (1H, s, pyrazole-H),
7.38–7.13 (16H, m, Tr-H, furyl-H), 6.40 (1H, dd, J = 3.6, 1.9 Hz, furyl-H), 6.31 (1H, d, J = 3.6 Hz,
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furyl-H); C-NMR (75 MHz, CDCl3): δ 146.8, 142.9, 140.6, 136.5, 130.1, 127.9, 127.8, 127.7, 127.2,