70
R. J. Abdel-Jalil and W. Voelter
Vol. 42
4-Fluoro-5-[4-(4-chlorophenyl)-1-piperazinyl]-2-nitroaniline (5c).
1,2-Diamino-4-fluoro-5-[4-(4-fluoroyphenyl)-1-piperazinyl]ben-
zene (6e).
The following spectral data were recorded for compound 5c:
1
H NMR: δ: 7.80 (d, J = 15.0 Hz, H-3), 7.24 (d, J = 7.5 Hz, 2H,
The following spectral data were recorded for compound 6e:
1
C H Cl), 6.87 (d, J = 7.5 Hz, 2H, C H Cl), 6.10 (d, J = 7.5 Hz,
H NMR: δ: 6.89-7.27 (m, 4H, C H F), 6.49 (d, J = 15.0 Hz, 1H,
6
4
6
4
6 4
H-6), 3.38 (bt, J = 3.0 Hz, 4H, C2'-H, C6'-H), 3.10 (bt, 4H, J =
H-3), 6.42 (d, J = 7.5 Hz, 1H, H-6), 3.26 (bt, J = 3.0 Hz, 4H, C2'-
H, C6'-H), 3.13 (bt, 4H, J = 3.1 Hz, 4H, C3'-H, C5'-H), 4.9 (bs,
3
.1 Hz, 4H, C3'-H, C5'-H), 5.10 (bs, 2H, NH2).
2
H, NH2).
4
-Fluoro-5-[4-(4-methoxyphenyl)-1-piperazinyl]-2-nitroaniline
(5d).
General Procedure for the Synthesis of Compounds 7a-e.
The following spectral data were recorded for compound 5d:
H NMR: δ: 7.73 (d, J = 14.2 Hz, H-3), 6.87 (d, J = 7.5 Hz, 2H,
A solution of the particular 1,2-diamino-4-fluoro-5-(4-substi-
tuted-1-piperazinyl)benzenes 6a-e (1 mmol) and ferrocenylcar-
boxaldehyde (3 mmol) in (15) ml of ethanol/nitrobenzene (1/3)
was refluxed for 1 h, then most of the ethanol was distilled off,
the temperature elevated to about 200-205 °C and maintained for
5 min. The reaction mixture was cooled and allowed to stand
over night at room temperature. Diethyl ether (20 ml) was then
added and the reaction mixture was allowed to stand for 1 h. The
resulting precipitate was collected and crystallized from diethyl
ether to give the title compounds.
1
C H OCH ), 6.84 (d, J = 7.5 Hz, 2H, C H OCH ), 6.06 (d, J =
6
4
3
6
4
3
7
.5 Hz, H-6), 3.72 (s, 3H, C H OCH ), 3.32 (bt, J = 3.2 Hz, 4H,
6 4 3
C2'-H,C6'-H), 3.15 (bt, 4H, J = 3.1 Hz, 4H, C3'-H, C5'-H), 5.7,
4
.5 (bs, bs, 1H, 1H, NH2).
4
-Fluoro-5-[4-(4-fluorophenyl)-1-piperazinyl]-2-nitroaniline (5e).
The following spectral data were recorded for compound 5e:
1
H NMR: δ: 7.79 (d, J = 14.2 Hz, H-3), 6.88-6.99 (m, 4H,
C H F), 6.12 (d, J = 7.5 Hz, H-6), 3.38 (bt, J = 3.2 Hz, 4H, C2'-
6
4
2
-Ferrocenyl-5-fluoro-6-(4-methyl-1-piperazinyl) benzimidazole
H, C6'-H), 3.24 (bt, 4H, J = 3.0 Hz, 4H, C3'-H and C5'-H), 5.4,
.9 (bs, bs, 1H, 1H, NH2).
(7a).
4
The following spectral data were recorded for compound 7a:
H NMR: δ: 12.23 (bs, 1H, N-H), 7.24 (2H*, H-4, H-7), 4.90 (bs,
General Procedure for the Synthesis of Compounds 6a-e.
1
To a solution of 5 (10 mmol) in conc. HCl (50 ml) was slowly
added stannous chloride (11.22 g, 60 mmol) at room temperature
during ten minutes. Stirring was continued for additional two
hours. The reaction mixture was then cooled (ice-water bath) and
treated gradually with a concentrated solution of sodium hydrox-
ide (40 %) until the solution is strongly alkaline (pH 12-13). The
resulting aqueous mixture was extracted with chloroform (3 X 50
ml). The organic layer was separated, filtered and concentrated in
vacuo. The resulting solid was collected by suction filtration and
crystallized from chloroform.
2H, C5H4), 4.40 (bs, 2H, C5H4), 4.12 (bs, 5H, C5H5), 3.09 (bt, J
= 3.2 Hz, 4H, C2'-H, C6'-H), 3.09 (bt, 4H, J = 3.0 Hz, 4H, C3'-H,
C5'-H), 2.36 (s, 3H, N-CH3). FT-IR (KBr disk): 3078, 2924,
2791, 1639, 1567, 1480, 1409, 1373, 1322, 1183, 1148, 1009,
845, 722 cm . EI-MS m/z : 418. *: These signals are masked by
the signal of CDCl3 peak.
-1
2
-Ferrocenyl-5-fluoro-6-(4-phenyl-1-piperazinyl)benzimidazole
(7b).
1
The following spectral data were recorded for compound 7b: H
NMR: δ: 11.73 (bs, 1H, N-H), 6.91-7.33 (m, 7H, C H , H-4, H-7),
6
5
1
,2-Diamino-4-fluoro-5-(4-methyl-1-piperazinyl)benzene (6a).
This compound has mp 96-97 °C (Lit. [4 ] mp 95-96 °C).
,2-Diamino-4-fluoro-5-(4-phenyl-1-piperazinyl)benzene (6b).
The following spectral data were recorded for compound 6b:
4
.85 (bs, 2H, C H ), 4.42 (bs, 2H, C H ), 4.22 (bs, 5H, C H ), 3.39
5 4 5 4 5 5
(bt, J = 3.0 Hz, 4H, C2'-H, C6'-H), 3.34 (bt, 4H, J = 3.2 Hz, 4H, C3'-
H, C5'-H). FT-IR (KBr disk): 2925, 2817, 1597, 1567, 1474, 1409,
1
-1
1
264, 1230, 1144, 941, 845, 818 cm . EI-MS m/z : 480.
2
-Ferrocenyl-5-fluoro-6-[4-(4-chlorophenyl)-1-piperazinyl]ben-
1
H NMR: δ: 6.877.26 (m, 5H, C H ), 6.52 (d, J = 14.0 Hz, 1H,
6
5
zimidazole (7c).
H-3), 6.41 (d, J = 7.5 Hz, 1H, H-6), 3.28 (bt, J = 3.0 Hz, 4H, C2'-
H, C6'-H), 3.14 (bt, 4H, J = 3.1 Hz, 4H, C3'-H, C5'-H), 4.7 (bs,
The following spectral data were recorded for compound 7c:
1
H NMR: δ: 11.73 (bs, 1H, N-H), 6.91-7.39 (m, 6H, C H Cl, H-
2
H, NH2).
6 4
4
, H-7), 4.92 (bs, 2H, C H ), 4.40 (bs, 2H, C H ), 4.11 (bs, 5H,
5 4 5 4
1
,2-Diamino-4-fluoro-5-[4-(4-chlororphenyl)-1-piperazinyl]ben-
C H ), 3.31 (bt, J = 3.0 Hz, 4H, C2'-H, C6'-H), 3.20 (bt, 4H, J =
5 5
zene (6c).
3.1 Hz, 4H, C3'-H, C5'-H). FT-IR (KBr disk): 3078, 2817, 2356,
-1
1
634, 1598, 1490, 1470, 1444, 1224, 1142, 1101, 942, 814 cm .
The following spectral data were recorded for compound 6c:
1
EI-MS m/z : 514/516.
H NMR: δ: 6.95 (d, J = 7.5 Hz, 2H, C H Cl), 6.86 (d, J = 7.5
6
4
Hz, 2H, C H Cl), 6.49 (d, J = 14.8 Hz, 1H, H-3), 6.42 (d, J =
6
4
2-Ferrocenyl-5-fluoro-6-[4-(4-methoxyphenyl)-1-piperazinyl]-
benzimidazole (7d).
7
.4 Hz, 1H, H-6), 3.31 (bt, J = 3.2 Hz, 4H, C2'-H, C6'-H), 3.22
(bt, 4H, J = 3.1 Hz, 4H, C3'-H, C5'-H), 5.3 (bs, 2H, NH2).
The following spectral data were recorded for compound 7d:
1
1
,2-Diamino-4-fluoro-5-[4-(4-methoxyphenyl)-1-piperazinyl]-
H NMR: δ: 12.30 (bs, 1H, N-H), 6.86-7.33 (m, 6H, C H OCH ,
6 4 3
benzene (6d).
H-4, H-7), 4.90 (bs, 2H, C H ), 4.44 (bs, 2H, C H ), 4.12 (bs,
5 4 5 4
5
H, C H ), 3.76 (s, 3H, C H OCH ), 3.25-3.29 (m, 8H, C2'-H ,
5 5 6 5 3
The following spectral data were recorded for compound 6d:
C2'-H, C3'-H, C5'-H). FT-IR (KBr disk): 3073, 2822, 2356,
1
m/z: 510.
1
H NMR: δ: 7.03 (d, J = 7.5 Hz, 2H, C H OCH ), 6.89 (d, J = 7.5
6
4
3
-1
634, 1506, 1470, 1413, 1229, 1137, 937, 814, 712 cm . EI-MS
Hz, 2H, C H OCH ), 6.55 (d, J = 15.0 Hz, 1H, H-3), 6.46 (d, J
6
4
3
=
7.5 Hz, 1H, H-6), 3.77 (s, 3H, C H OCH ), 3.24 (bt, J = 3.0
6 4 3
Hz, 4H, C2'-H, C6'-H), 3.12 (bt, 4H, J = 3.1 Hz, 4H, C3'-H, C5'-
H), 4.3 (bs, 2H, NH2).
2-Ferrocenyl-5-fluoro-6-[4-(4-fluorophenyl)-1-piperazinyl]benz-
imidazole (7e).