3304
T.A. Brandt et al. / Tetrahedron 65 (2009) 3292–3304
540. 1H NMR (400 MHz, DMSO-d6):
d
8.15 (br s, 1H), 7.52–7.18 (m,
was obtained as an off-white solid (6.4 g, 58% overall yield), spectral
data for which matched that reported in the previous procedure.
8H), 1.95 (s, 3H). 13C NMR (100 MHz, DMSO-d6) (7 of 15 signals
observed): d 133.1, 130.6, 130.4, 128.3, 128.3, 128.2, 30.2. Anal. Calcd
for C15H11Cl2N3: C, 59.14; H, 4.09; N, 16.23. Found: C, 59.44; H, 4.47;
N, 15.33.
References and notes
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6.2.5. Telescoped conversion of bromoketone 24 to
pyrazolotriazinone 10
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Bromoketone 24 (10.26 g, 30.0 mmol) was dissolved in ethanol
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0 ꢀC. To this turbid solution was added N-benzhydrylth-
iosemicarbizide 26c (8.10 g, 31.5 mmol), and the resulting suspen-
sion was allowed to warm to room temperature and stirred
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night in a vacuum oven (30 ꢀC, 20–30 mm). The title product (10)
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