HETEROCYCLES, Vol. 85, No. 4, 2012
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crude products, which were further purified by recrystallization from TFA. This compound was obtained
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as pale yellow powder in 58% yield, mp >300 C. IR (KBr) ν/cm-1: 1629 (C=O), 1433 (C=N); H NMR
(600 MHz, DMSO-d6): δ (ppm): 7.26 (d, J=15.6 Hz, 2H, =CH), 7.33-7.46 (m, 6H, ben-H and =CH), 7.52
(dd, J=10.8, 10.8 Hz, 2H, tropolone-H), 7.79-7.87 (m, 2H, tropone-H), 8.13 (d, J=10.8 Hz, 2H,
tropone-H), 8.39 (d, J=10.8 Hz, 2H, tropone-H); 13C NMR (150 MHz, DMSO-d6): δ (ppm): 116.74,
122.30, 122.94, 126.17, 126.84, 131.98, 140.32, 141.27, 143.79, 152.27, 158.69, 178.42; ESI-MS m/z:
421.0 (M+1)+. Anal. Calcd for C26H16N2O4: C, 74.28; H, 3.84; N, 6.66. Found: C, 74.44; H, 3.64; N, 6.49.
General procedure for the synthesis of 3,3'-{1,4-phenylenebis[(E)ethene-2,1-diyl]}bis[1-(aryl)-
cyclohepta[c]pyrazol-8(1H)-one]s (3-5). To a solution of 3,3'-{1,4-phenylenebis[(1E)-3-oxoprop-1-ene-
1,3-diyl]}bistropolone (1) (0.43 g, 1 mmol) in 10 mL of n-BuOH was added the corresponding
phenylhydrazine hydrochloride (2 mmol). The resulting mixture was heated at reflux for 24 hours. After
the reaction was complete (TLC), the mixture was cooled to room temperature, and then poured into
some water, filtered to give the crude products, which were further purified by recrystallization from
TFA.
3,3'-{1,4-Phenylenebis[(E)ethene-2,1-diyl]}bis[1-(phenyl)cyclohepta[c]pyrazol-8(1H)-one] (3). This
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compound was obtained as yellow crystals in 53% yield, mp >300 C. IR (KBr) ν/cm-1: 1644 (C=O),
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1485 (C=N); H NMR (600 MHz, DMSO-d6): δ (ppm): 7.39 (d, J=15.6, 2H, =CH), 7.47-7.51 (m, 6H,
ben-H), 7.58-7.69 (m, 4H, ben-H and =CH), 7.83-7.87 (m, 6H, ben-H and tropone-H), 8.07-8.12 (m, 4H,
ben-H and tropone-H), 8.38 (d, J=10.8 Hz, 2H, tropone-H), 8.54 (d, J=10.8 Hz, 2H, tropone-H); 13C
NMR (150 MHz, DMSO-d6): δ (ppm): 113.96, 115.37, 123.53, 123.89, 124.15, 127.57, 129.88, 132.09,
133.40, 135.68, 136.10, 136.56, 149.07, 151.17, 153.21, 178.82; ESI-MS m/z: 571.1 (M+1)+. Anal. Calcd
for C38H26N4O2: C, 79.98; H, 4.59; N, 9.82. Found: C, 80.20; H, 4.40; N, 9.83.
3,3'-{1,4-Phenylenebis[(E)ethene-2,1-diyl]}bis[1-(4-chlorophenyl)cyclohepta[c]pyrazol-8(1H)-one]
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(4). This compound was obtained as yellow crystals in 51% yield, mp >300 C. IR (KBr) ν/cm-1: 1644
(C=O), 1485 (C=N); 1H NMR (600 MHz, DMSO-d6): δ (ppm): 7.36 (d, J=15.6, 2H, =CH), 7.43 (d, J=7.2
Hz, 4H, ben-H), 7.61-7.70 (m, 6H, ben-H and =CH), 7.81-7.92 (m, 6H, ben-H and tropone-H), 8.11-8.15
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(m, 2H, tropone-H), 8.40 (d, J=10.8 Hz, 2H, tropone-H), 8.55 (d, J=10.8 Hz, 2H, tropone-H); C NMR
(150 MHz, DMSO-d6): δ (ppm): 115.55, 116.18, 122.43, 123.48, 124.61, 126.57, 131.68, 132.26, 134.30,
135.85, 136.81, 142.56, 148.92, 150.34, 152.94, 179.36; ESI-MS m/z: 639.3 (M+1)+. Anal. Calcd for
C38H24Cl2N4O2: C, 71.37; H, 3.78; N, 8.76. Found: C, 71.53; H, 3.76; N, 8.81.
3,3'-{1,4-Phenylenebis[(E)ethene-2,1-diyl]}bis[1-(4-bromophenyl)cyclohepta[c]pyrazol-8(1H)-one]
(5). This compound was obtained as yellow crystals in 50%, mp >300 oC. IR (KBr) ν/cm-1: 1642 (C=O),
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1484 (C=N); H NMR (600 MHz, DMSO-d6): δ (ppm): δ 7.41 (d, J=15.6 Hz, 2H, =CH), 7.45 (d, J=7.2
Hz, 4H, ben-H), 7.49-7.55 (m, 4H, ben-H), 7.63-7.71 (m, 4H, =CH and tropone-H), 7.81 (d, J=7.2 Hz, 4H,