688
Vol. 38
M. H. Mohamed, M. M. Abdel-Khalik and M. H. Elnagdi
solid product, so formed, was collected by filtration and
crystallized from ethanol to give red crystals; yield: 2.08 g
overnight. The solid product obtained was collected by filtration
and crystallized from benzene as white crystals; yield: 1.26 g
(70%), mp 259-260° ; ir: 3210 (NH), 1680, 1695 (CO) cm ; H
NMR (DMSO-d ): δ 2.06 (s, 3H, CH ), 2.56 (s, 3H,
6 3pyrazolyl C-5
-1
1
-1 1
(78%), mp 137-138°; ir: 1710 cm (CO); H NMR (DMSO-d ):
6
δ 1.99 (s, 3H, CH
), 2.19 (s, 3H, CH
6.07 (s, 1H, pyrazolyl 4-H), 7.02-7.85 (m, 7H, arom H).
Anal. Calcd. for C N O (266.29): C, 67.65; H, 5.30; N,
),
3pyrazolyl C-5
3pyrazolyl C-3
CH
), 2.35 (s, 3H, CH ), 6.35 (s, 1H, pyrazole H-4),
3pyrazolyl C-3
3
13
H
8.12 (br s, 1H, NH); C NMR (DMSO): δ 178.4 (CO), 176.2
(CO), 132.3, 129.6, 106.2 (pyrazolyl C), 24.30, 24.10, 22.5
(3CH ); ms: m/z 181 (M ).
15 14
4
21.04. Found: C, 67.52; H, 5.30; N, 21.03.
3',5'-Dimethyl-1-(1,2-diphenylhydrazonopropanyl)-pyrazole (9).
Method A.
+
3
Anal. Calcd. for C H N O (181.19): C, 53.03; H, 6.12; N,
8
11 3 2
23.19. Found: C, 53.17; H, 6.08; N, 23.06.
6-Amino-4-hydroxy-2-phenyl-3-(3',5'-dimethylpyrazol-1'-
yl)benzonitrile (14).
A mixture of 5a (2.56 g, 10 mmoles) and phenylhydrazine
(1.08 g, 10 mmoles) and acetic acid (1 ml) was heated at 120° for
10 minutes. The reaction mixture was triturated with ethanol, the
solid product, so formed, was collected by filtration and crystal-
lized from ethanol to give red crystals in a yield of 75%.
Method A.
To a solution of 4 (1.52 g, 10 mmoles) in dioxan (30 ml), ben-
zylidenemalononitrile (1.54 g, 10 mmoles) was added in the pres-
ence of few drops of piperidine. The reaction mixture was heated
under reflux for 6 hours. The solvent was reduced under vacuum,
diluted with water and acidified with dilute HCl. The solid prod-
uct obtained was collected by filtration and crystallized from
ethanol as green crystals in a yield of 70%.
Method B.
A cold solution of benzenediazonium chloride (prepared as
previously discussed in compound 5a), was added to a solution of
compound 10 (1.82 g, 10 mmoles) in 50 ml ethanol containing 2
g NaOH. The reaction mixture was stirred for 1 hour. at room
temperature and was left overnight in the refrigerator. The solid
product, so formed, was collected by filtration and crystallized
from ethanol to give red crystals in a yield of 64%; yield: 2.60 g
Method B.
To a solution of 15 (2.40 g, 10 mmoles) in dioxan (30 ml),
malononitrile (0.66 g, 10 mmoles) was added in the presence of few
drops of piperidine. The reaction mixture was heated under reflux
for 6 hours. The solvent was reduced under vacuum, diluted with
water and acidified with dilute HCl. The solid product obtained was
collected by filtration and crystallized from ethanol as green crystals
63%; yield: 2.12 g (70%) (method A), mp 141-142°; ir: 3465 (OH),
-1
1
(75%), mp 167-168°; ir: 3431 (NH), 2980, 2850 (CH ) cm ;
H
3
NMR (DMSO-d ): δ 1.89 (s, 3H, CH
), 2.55 (s, 3H,
), 2.65 (s, 3H, CH ), 6.35 (s, 1H, pyrazole 4-H),
6
3pyrazolyl C-5
CH
3pyrazolyl C-3
3
7.28-7.83 (m, 10H, arom. H), 8.12 (br s, 1H, NH), 8.15 (br s, 1H,
NH).
Anal. Calcd. for C
H N (346.42): C, 69.34; H, 6.40; N,
20 22 6
-1
1
24.26. Found: C, 69.35; H, 6.42; N, 24.48.
3420, 3328 (NH ), 2208 cm (CN); H NMR (DMSO-d ): δ 2.01
2
6
(s, 3H, CH
), 2.25 (s, 3H, CH
), 6.35 (s, 1H,
3pyrazolyl C-5
3pyrazolyl C-3
1-(3′,5′-Dimethylpyrazol-1′-yl)-2-phenylhydrazonopropane (10).
pyrazole 4-H), 7.35-7.65 (m, 6H, arom. H), 8.72 (br s, 2H, NH ),
2
+
A mixture of 4 (1.52 g, 10 mmoles) and phenylhydrazine in
presence of acetic acid (1 ml) was heated at 120° for 10 minutes.
The reaction mixture was triturated with ethanol, the solid prod-
uct, so formed, was collected by filtration and crystallized from
ethanol to give yellow crystals; yield: 2.17 (90%), mp 128-129°;
9.65 (s, 1H, OH); ms: m/z304 (M ).
Anal. Calcd. for C
H N O (304.34): C, 71.03; H, 5.30; N,
18 16 4
18.41. Found: C, 57.19; H, 7.88; N, 25.30.
2-(3',5'-Dimethylpyrazol-1'-yl)-1-phenylbutene-3-one (15).
-1
1
ir: 3238 cm (NH); H NMR (DMSO-d ): δ 1.89 (s, 3H,
To a solution of 4 (1.52 g, 10 mmoles) in dioxan (30 ml),
benzaldehyde (1.06 g, 10 mmoles) was added in the presence of
few drops of piperidine. The reaction mixture was heated under
reflux for 15 minutes. The solvent was reduced under vacuum,
diluted with water and acidified with dilute HCl. The solid
product obtained was collected by filtration and crystallized from
ethanol as yellow crystals; yield: 1.99 g (83%), mp 123-124°; ir:
6
CH
), 2.52 (s, 3H, CH
), 2.65 (s, 3H, CH ),
3pyrazolyl C-5
3pyrazolyl C-3 3
4.45 (s, 2H, CH ), 6.82 (s, 1H, pyrazolyl 4-H), 7.23-7.55 (m, 5H,
2
arom H.), 8.20 (br s, 1H, NH).
Anal. Calcd. for C
H N (242.32): C 69.39, H 7.49, N 23.12;
14 18 4
found C 69.19, H 7.60, N 23.30.
3-(3',5'-Dimethylpyrazol-1'-yl)-2-methylindole (11).
-1
1
1710 cm (CO); H NMR (DMSO-d ): δ 2.05 (s, 3H,
6
A mixture of compound 4 (1.52 g, 10 mmoles) and phenyl-
hydrazine hydrochloride (1.44 g, 10 mmoles) in dioxane (30 ml)
was heated for 5 hours. The solvent was evaporated under
vacuum and crystallized from ethanol as brown crystals; yield:
CH
), 2.35 (s, 3H, CH
), 2.65 (s, 3H, CH ),
3pyrazolyl C-5
3pyrazolyl C-3 3
5.67 (s, 1H, olefinic-H), 6.35 (s, 1H, pyrazolyl 4-H), 7.25-7.68
+
(m, 5H, arom. H). ms: m/z 240 (M ).
Anal. Calcd. for C
H N O (240.29): C, 74.97; H, 6.71; N,
15 17 2
-1
1
1.80 g (80%), mp 259-260° ; ir: 3.210 cm (NH); H NMR
(DMSO-d ): δ 2.02 (s, 3H, CH ), 2.19 (s, 3H,
11.66. Found: C, 74.66; H, 6.97; N, 11.61.
6
3pyrazolyl C-5
CH
), 2.21 (s, 3H, CH
), 6.04 (s, 1H, pyra-
3pyrazolyl C-3
3 indolyl C-2
REFERENCES AND NOTES
zolyl 4-H), 6.99-7.38 (m, 4H, arom. H.), 11.33 (br s, 1H, NH).
Anal. Calcd. for C N (225.28): C, 74.64; H, 6.71; N,
H
14 15
3
[1] M. Kolb, Synthesis, 171 (1990).
[2] F. Al-Omran, A. A. El-Khair and M. H. Elnagdi, Org. Prep.
Proced. Int., 30, 211 (1998).
[3] Y. Matsuda, S. Ide, K. Furuno, T. Itou, C. Motokawa and
Y. Chiyomaru, Tetrahedron, 49, 9947 (1993).
[4] A. A. Al-Naggar, M. M. Abdel-Khalik and M. H. Elnagdi,
J. Chem. Research (S) 648-649 (1999), (M) 2801 (1999).
18.65. Found: C, 74.66; H, 6.67; N, 18.67.
1-(3',5'-Dimethylpyrazol-1'-yl)-N-acetylformamide (13).
To a cold solution of 4 (1.52 g, 10 mmoles) in (30 ml) acetic
acid, a solution of sodium nitrite was added (0.7 g, 10 mmoles)
was added drop wise at 0° . The reaction mixture was left