Pyridazine Derivatives and Related Compounds, Part 8 283
168–169◦ (ethanol); IR: 3390–3260 (OH), 1611 (C N)
and 1520 cm−1 (C C); 1H NMR (DMSO-d6): δ (ppm):
7.4–6.9 (m, 15H, 3Ph) and 5.63–3.10 (m, 11H, sugar-
H).
Anal. Calcd for C28H26N4O5: C, 67.46; H, 5.26; N,
11.24. Found: C, 67.30; H, 5.10; N, 11.10.
and 1510 cm−1 (C C); 1H NMR (DMSO-d6): δ (ppm):
7.2–6.9 (m, 15H, 3Ph), 4.8–4.4 (q, 2H, CH2), and 1.2
(t, 3H, CH3).
Anal. Calcd for C26H20N4O2: C, 74.27; H, 4.79; N,
13.33. Found: C, 74.10; H, 4.70; N, 13.20.
2,3,4-Trihydro-7,8,9-triphenylpyridazino[3,2-c]-
1,2,4-triazine-3,4-dione 14
2-(4,5,6-Triphenylpyridazin-3-yl)hydrazonopro-
pionic Acid 11
To a solution of 1 (1.0 g, 3 mmol) in pyridine (15 mL),
oxalyl chloride (0.4 g, 3 mmol) was added. The mix-
ture was stirred at r.t. for 30 min. The reaction mix-
ture was then poured onto water (100 mL). The sep-
arated solid product was filtered, 0.8 g (69%) of 14;
mp > 300◦ (ethanol); IR : 1720–1680 (2C O), 1610
A stirred solution of 1 (1.0 g, 3 mmol) in acetic
acid (10 mL) was treated with pyruvic acid (0.26 g,
3 mmol). The white precipitate that separated out
immediately was filtered off and washed with water,
affording 0.89 g (73%) of 11; mp 162–163◦ (ethanol);
IR : 3350 (OH), 1720 (C O), 1600 (C N), and 1525
1
(C N), and 1525 cm−1 (C C); H NMR (CDCl3): δ
1
cm−1 (C C); H NMR (DMSO-d6): δ (ppm): 7.5–6.8
(ppm): 7.8–6.3 (m, 15H, 3Ph).
(m, 15H, 3Ph) and 1.8 (s, 3H, CH3).
Anal. Calcd for C25H20N4O2: C, 73.51; H, 4.94; N,
13.72. Found: C, 73.40; H, 4.80; N, 13.60.
Anal. Calcd for C24H16N4O2: C, 73.46; H, 4.11; N,
14.28. Found: C, 73.40; H, 4.00; N, 14.10.
3-[(4,5,6-Triphenylpyridazin-3-yl)-hydrazono]-
butan-2-one 15
3-Methyl-7,8,9-triphenylpyridazino[3,2-c]-1,2,4-
triazin-4-one 12
A mixture of 1 (1.0 g, 3 mmol) and diacetyl (0.26 g,
3 mmol) in absolute ethanol (30 mL) was refluxed
for 3 h. Upon cooling the solid product was fil-
tered, 0.48 g (40%) of 15; mp 257–258◦ (ethanol); IR:
3400–3250 (NH), 2980–2840 (CH), 1670 (C O), 1620
(C N), and 1490 cm−1 (C C).
Compound 11 (1.0 g, 2.4 mmol) was heated in oil
bath at 150◦ for 10 min upon cooling to r.t. followed
by trituration with ethanol. The solid product was
filtered, 0.67 g (70%) of 12; mp 288–289◦ (ethanol);
IR: 1700 (C O), 1620 (C N), and 1515 cm−1 (C C);
1H NMR (DMSO-d6): δ (ppm) : 7.6–6.9 (m, 15H, 3Ph)
and 2.0 (s, 3H, CH3).
Anal. Calcd for C26H22N4O: C, 76.83; H, 5.46; N,
13.78. Found: C, 76.70; H, 5.40; N, 13.60.
Anal. Calcd for C25H18N4O: C, 76.91; H, 4.65; N,
14.35. Found: C, 76.80; H, 4.60; N, 14.20.
2,3-Butanedione-2,3-bis(4,5,6-triphenylpyri-
dazin-3-ylhydrazone) 16
3,3ꢁ-Bis(6,7,8-triphenyl-1,2,4-triazolo[4,3-b]-
Method A. By refluxing of compound 1 (6.77 g,
20 mmol) and diacetyl (0.86 g, 10 mmol) in glacial
acetic acid (30 mL) for 3 h, upon cooling the solid
product was filtered, 5.8 g (80%) of 16; mp 172–173◦
(DMF); IR: 3410–3320 (NH), 2980–2930 (CH), 1620
(C N), and 1510 cm−1 (C C).
pyridazine) 13
To a solution of 1 (2.0 g, 5.9 mmol) in acetic acid
(30 mL), diethyl oxalate (15.0 g, 0.1 mol) was added.
The mixture was refluxed for 1 h. The solid product,
which separated out on cooling was filtered, 1.84 g
(90%) of 13; mp > 300◦ (DMF); IR : 1610 (C N) and
1520 cm−1 (C C); 1H NMR (DMSO-d6): δ (ppm): 7.6–
7.0 (m, 30H, 6Ph).
Anal. Calcd for C48H38N8: C, 79.31; H, 5.27; N,
15.42. Found: C, 79.20; H, 5.00; N, 15.30.
Method B. By refluxing of compound 15 (0.8 g,
2 mmol) and 1 (1.0 g, 3 mmol) in glacial acetic acid
(30 mL) for 3 h, upon cooling the solid product was
filtered and crystallized from DMF to give 1.4 g (96%)
of 16. It was identical in every respect with that pre-
pared by method A.
Anal. Calcd for C46H30N8: C, 79.52; H, 4.35; N,
16.13. Found: C, 79.40; H, 4.30; N, 16.00.
Ethyl 6,7,8-triphenyl-1,2,4-triazolo[4,3-b]-
pyridazine-3-carboxylate 10c
A mixture of 1 (2.0 g, 5.9 mmol) and oxalylchloride
(15 mL) was stirred at r.t. for 30 min. The separated
solid product was collected, then refluxed in ethanol
(30 mL) for 5 min. The solid product, which sepa-
rated out on cooling was filtered, 2.0 g (80%) of 10c;
mp 200–201◦ (ethanol); IR : 1720 (C O), 1625 (C N),
3-[N-(1,3-Dihydro-1,3-dioxo-2H-isoindol-2-
yl)]amino-4,5,6-triphenylpyridazine 17
A mixture of 1 (1.69 g, 5 mmol) and phthalic acid an-
hydride (0.74 g, 5 mmol) in absolute ethanol (50 mL)