Novel synthesis of N-{6-aryl-4-[(E)-2-furylmethylene]-1,2,3,4-tetrahydro-3- oxopyridazin-1-ylcarbonyl}-p-toluenesulfonamides and n-{5-[(E)-1-aroylmethyl-2-(2-furyl) vinyl]-1,3,4-oxadiazol-2-yl}-p-toluenesulfonamides

Article abstract of DOI:10.1002/jhet.5570390634

Novel N-{6-aryl-4-[(E)-2-furylmethylene]-1,2,3,4-tetrahydro-3- oxopyridazin-1-ylcarbonyl}-p-toluene-sulfonamides 4a-d were prepared by the reaction of (E)-2-aroylmethyl-3-(2-furyl) acrylohydrazides 2a-d with tosylisocyanate. This has been shown to occur b

Full text of DOI:10.1002/jhet.5570390634

Nov-Dec 2002
Novel Synthesis of N-{6-Aryl-4-[(E)-2-furylmethylene]-1,2,3,4-
tetrahydro-3-oxopyridazin-1-ylcarbonyl}-p-toluenesulfonamides
and N-{5-[(E)-1-Aroylmethyl-2-(2-furyl) vinyl]-1,3,4-
oxadiazol-2-yl}-p-toluenesulfonamides
1325
Abdel-Sattar S. Hamad* and Ahmed I. Hashem
Department of Chemistry, Faculty of Science, University of Ain Shams, Abbassia 11566, Cairo, Egypt
Tel./ Fax; (00) 202-4831836 E-mail; hamad@asunet.shams.eun.eg
Received July 18, 2002
Novel N-{6-aryl-4-[(E)-2-furylmethylene]-1,2,3,4-tetrahydro-3-oxopyridazin-1-ylcarbonyl}-p-toluene-
sulfonamides 4a-d were prepared by the reaction of (E)-2-aroylmethyl-3-(2-furyl) acrylohydrazides 2a-d
with tosylisocyanate. This has been shown to occur by initial formation of (E)-2-aroylmethyl-3-(2-furyl)-N'-
(tosylaminocarbonyl) acrylohydrazides 3a-d followed by acid catalyzed cyclization to afford N-{5-[(E)-1-
aroylmethyl-2-(2-furyl)vinyl]-1,3,4-oxadiazol-2-yl}-p-toluenesulfonamides 5a-d.
J. Heterocyclic Chem., 39, 1325(2002).
Introduction.
Conversion of the 2(3H)-furanones 1a-d into the corre-
sponding 3(2H)-pyridazones 4a-d and oxadiazoles 5a-d
are of potential biological interest [6-10]. Usually, 3(2H)-
pyridazinones are prepared from -oxoalkanoic acid deriv-
atives and hydrazines [11] and 1,3,4-oxadiazoles are
prepared from 1,2-diacylhydrazines [12]. We report here
the preparation of (E)-2-aroylmethyl-3-(2-furyl)-N'-(tosyl-
aminocarbonyl)acrylohydrazides 3a-d, which, upon acid
catalyzed cyclization, furnished N-{6-aryl-4-[(E)-2-furyl-
methylene]-1,2,3,4-tetrahydro-3-oxopyridazin-1-yl car-
bonyl}-p-toluenesulfonamides 4a-d and N-{5-[(E)-1-
aroylmethyl-2-(2-furyl)vinyl]-1,3,4-oxadiazol-2-yl}-p-
toluenesulfonamides 5a-d.
In connection with our synthetic approach to the 5-aryl-
3-[(E)-2-furylmethylene]furan-2(3H)-ones 1a-d [1-4],
these compounds were isolated in almost quantitative yield
upon condensation reaction of furan-2-carboxaldehyde
with 3-aroylpropionic acids under Perkin conditions yield-
ing the E-lactones as the only product and there is no
1
detectable amount of the Z-isomers by H NMR [5].
2(3H)-Furanones 1a-d react with hydrazine hydrate in
ethanol to give (E)-2-aroylmethyl-3-(2-furyl)acrylo-
hydrazides 2a-d, which were found to be useful precursors
in the synthesis of several heterocyclic compounds [4].
Scheme 1

1326
A.-S. S. Hamad and A. I. Hashem
Vol. 39
EXPERIMENTAL
Results and Discussion.
Reaction of (E)-2-aroylmethyl-3-(2-furyl)acrylohy-
drazides 2a-d with tosylisocyanate at 0–25 °C gave (E)-
2-aroylmethyl-3-(2-furyl)-N'-(tosylaminocarbonyl) acry-
lohydrazides 3a-d, and N-{6-aryl-4-[(E)-2-furylmethyl-
ene]-1,2,3,4-tetrahydro-3-oxopyridazin-1-ylcarbonyl}-p-
toluenesulfonamides 4a-d. Formation of product 3a-d
and 4a-d was dependent on the reaction conditions.
When the reaction was carried out at 0–5 °C for 12 h, (E)-
2-aroylmethyl-3-(2-furyl)-N'-(tosylaminocarbonyl)-
acrylohydrazides 3a-d were obtained in 31–45% yield.
However, treatment of 2a-d with tosylisocyanate at 25 °C
for 48 h gave N-{6-aryl-4-[(E)-2-furylmethylene]-
1,2,3,4-tetrahydro-3-oxopyridazin-1-yl carbonyl}-p-
toluenesulfonamides 4a-d in 75–82% yield. 3(2H)-
Pyridazinones 4a-d were also obtained by cyclization of
hydrazides 3a-d in a mixture of acetonitrile and 1 N
hydrochloric acid. Treatment of hyrazides 3a-d with
phosphorus oxychloride under reflux furnished the corre-
sponding N-{5-[(E)-1-aroylmethyl-2-(2-furyl)vinyl]-
1,3,4-oxadiazol-2-yl}-p-toluenesulfonamides 5a-d in
75–81% yield as shown in Scheme 1.
1H NMR spectra were recorded on Varian Plus 300 (300
MHz) or Bruker XL 300 (300 MHz) instruments, the 13C NMR
spectra (with DEPT 135) on a Bruker WP80 or XL 300 instru-
ment. Infrared Red spectra were taken on a Perkin Elmer 1600
FT-IR spectrometer. Mass points were recorded on a Kratos
Concept instrument. Melting points were measured on an
Electrothermal digital melting point apparatus and are uncor-
rected. The R values reported for TLC analyses were determined
f
on Macherey-Nagel 0.25 mm layer fluorescent UV
plates
254
with the indicated solvent system. M-H-W Laboratories
(Phoenix, AZ) performed elemental analyses.
(E)-2-Aroylmethyl-3-(2-furyl)-N'-(tosylaminocarbonyl)acrylo-
hydrazides 3a-d.
General Procedure A.
To a suspension of (E)-2-aroylmethyl-3-(2-furyl)acrylohy-
drazides 2a-b (2 mmoles) in acetonitrile (2 ml) under a nitrogen
atmosphere at 0–5°, p-toluenesulfonyl isocyanate (0.3 ml, 2.1
mmoles) was added and the mixture was stirred at 0–5° for 12
hours. The precipitate was collected by filtration to give 3a-d.
Analytical data for compounds 3a-d are given in Tables 1 and 2.
N-{6-Aryl-4-[(E)-2-furylmethylene]-1,2,3,4-tetrahydro-3-oxo-
pyridazin-1-ylcarbonyl}-p-toluenesulfonamides 4a-d.
General Procedure B.
The structures of novel compounds 3-5 were determined
by spectroscopic methods and analyses for C, H, N and S.
The IR spectral data for compounds 4b,d are in agreement
with the data of related 1-benzoyl-6-aryl-4-thienylidene-
1,6-dihydropyridazin-3-(2H)ones [13].
To a suspension of (E)-2-aroylmethyl-3-(2-furyl)acrylo-
hydrazides 2a-d (2 mmoles) in acetonitrile (2 ml) under nitrogen
atmosphere at 0–5°, p-toluenesulfonylisocyanate (0.3 ml, 2.1
mmoles) was added and the mixture was stirred at 0–5° for 12
hours and then at 25° for 48 hours. The solvent was evaporated in
vacuo, and the solid residue was recrystallized from ethanol to
give 4a-d.
Conclusion.
N-{6-aryl-4-[(E)-2-furylmethylene]-1,2,3,4-tetra-
hydro-3-oxopyridazin-1-ylcarbonyl}-p-toluenesulfon-
amides 4a-d and N-{5-[(E)-1-aroylmethyl-2-(2-
furyl)vinyl]-1,3,4-oxadiazol-2-yl}-p-toluenesulfon-
amides 5a-d were prepared in one step by acid cat-
alyzed cyclization of (E)-2-aroylmethyl-3-(2-furyl)-N'-
(tosylaminocarbonyl) acrylohydrazides 3a-d in good
yields.
General Procedure C.
To a suspension of (E)-2-aroylmethyl-3-(2-furyl)-N2-(tosy-
laminocarbonyl)acrylohydrazides 3a-d (1 mmole) in acetonitrile
(4 ml), 1.0 N hydrochloric acid (1 ml) was added and the mixture
was stirred at 25° for one hour. The solvent was evaporated in
vacuo and the solid residue was recrystallized from ethanol to
give 4a-d. Analytical data for compounds 4a-d are given in
Tables 1, 2.
Table 1
Physical and Elemental Analytical Data for Compounds 3-5
No.
Alkyl
group
mp °C(Solvent)
Yield%
Formula
[Cald./found]
C
H
N
S
3a
3b
3c
3d
4a
4b
4c
4d
5a
5b
5c
5d
H
110-112 (Acetonitrile)
133-135 (Acetonitrile)
125-127 (Acetonitrile)
190-192 (Acetonitrile)
156-158 (Ethanol)
175-177 (Ethanol)
168-170 (Ethanol)
185-186 (Ethanol)
145-147 (Acetonitrile
176-177 (Acetonitrile
178-180 (Acetonitrile
166-168 (Acetonitrile
45
32
31
34
75
82
82
77
75
80
81
75
C
C
C
H
N O S
59.09/59.05 4.52/4.62 8.98/8.78 6.85/6.73
59.98/59.86 4.82/4.85 8.74/8.74 6.67/6.68
58.05/58.01 4.66/4.65 8.46/8.57 6.45/6.77
55.03/55.15 4.01/3.99 8.37/8.36 6.38/6.42
61.45/61.55 4.26/4.16 9.34/9.28 7.13/7.33
62.19/62.18 4.56/4.55 9.06/9.09 6.91/6.89
60.11/60.15 4.41/4.45 8.76/8.76 6.68/6.77
57.08/57.05 3.74/3.73 8.68/8.66 6.62/6.62
61.45/61.55 4.26/4.16 9.34/9.28 7.13/7.33
62.19/62.18 4.56/4.55 9.06/9.09 6.91/6.89
60.11/60.15 4.41/4.45 8.76/8.76 6.68/6.77
57.08/57.05 3.74/3.73 8.68/8.66 6.62/6.62
23 21 3 6
H N O S
CH
OCH
Cl
24 23 3 6
3
H
N O S
24 23 3 7
3
C
C
C
C
C
C
C
C
C
H ClN O S
23 20 3 6
23 19 3 5
24 21 3 5
24 21 3 6
23 18 3 5
23 19 3 5
24 21 3 5
24 21 3 6
H
H
N O S
H N O S
H
H ClN O S
H
H N O S
H
H ClN O S
CH
OCH
Cl
H
3
N O S
3
N O S
CH
OCH
Cl
3
N O S
3
23 18 3 5

Nov-Dec 2002
Novel Synthesis of N-{6-Aryl-4-[(E)-2-furylmethylene]-1,2,3,4-tetrahydro-
3-oxopyridazin-1-ylcarbonyl}-p-toluenesulfonamides
1327
Table 2
1
Infrared (IR) and H NMR (300 MHz) spectral Data for Compounds 3-5
-1
1
Cpd.No Alkyl
group
(IR)n
n
(Nujol)/cm
H NMR [deuteriodimethyl sulfoxide]
max
; n
n
C=O C=N; -NH
3a
H
1667(s), 1725(w), 3112(w),
3263.6(s)
d = 2.36 (s, 3H, Ar-CH ), 3.85 (s, 2H, CH COPh), 6.63 (dd, 1H, J = 1.8, 3.3 Hz, Furan-H4),
3 2
7.04 (d, 1H, J = 3 Hz, Furan-H3), 6.75 (s, 1H, furan-CH=C-), 7.35 (d, 2H, J = 8.4 Hz, Ar-H),
7.37-7.43 (m, 5H, Ph-H), 7.64 (d, J = 1.8 Hz, Furan-H5), 7.75 (d, 2H, J = 8.1 Hz, Ar-H), 9.30
(s, 1H, -NH-NH-), 10.67 (s, 1H,-NH-NH-), 11.63 (s, 1H, -CONHSO -Ar) ppm.
2
3b
CH
1667(s), 1699, 1725.8(w),
3099(w), 3266.6(S)
d = 2.36 (s, 3H, Ar-CH ), 2.37 (s, 3H, Ar-CH ), 3.88 (s, 2H, CH COAr), 6.70 (s, 1H, furan-
3 3 2
3
CH=C-), 6.87 (d, 2H, J = 9 Hz, Ar-H), 7.00 (d, 1H, J = 3.6 Hz, Furan-H3), 7.14 (dd, 1H, J =
1.8, 3.6 Hz, Furan-H4), 7.32 (d, 2H, J = 8.1 Hz, Ar-H), 7.45 (d, 2H, J = 9 Hz, Ar-H), 7.69 (d,
2H, J = 7.5 Hz, Ar-H), 7.82 (s, 1H, -NH-NH-), 7.96 (d, J = 1.5 Hz, Furan-H5), 8.28 (s, 1H,
-NH-NH-), 10.68 (s, 1H, -CONHSO2-Ar) ppm.
3c
OCH
Cl
1651(s), 1680(s), 1737(w),
3214(s), 3376(w)
d = 2.44 (s, 3H, Ar-CH3), 3.80 (s, 3H, Ar-OCH3), 3.85 (s, 2H, CH2COAr), 6.75 (d, 1H, J = 3
Hz, furan-CH=C-), 6.85 (d, 2H, J = 9 Hz, Ar-H), 7.05 (d, 1H, J = 3.6 Hz, Furan-H3), 7.12 (dd,
1H, J = 1.8, 3.6 Hz, Furan-H4), 7.37 (d, 2H, J = 8.1 Hz, Ar-H), 7.41 (d, 2H, J = 9 Hz, Ar-H),
7.71 (d, 2H, J = 7.5 Hz, Ar-H), 7.81 (s, 1H, -NH-NH-), 7.95 (d, J = 1.5 Hz, Furan-H5), 8.27
(s, 1H, -NH-NH-), 10.68 (s, 1H, -CONHSO2-Ar) ppm.
d = 2.38 (s, 3H, Ar-CH3), 3.79 (s, 2H, CH2COAr), 6.61 (s, 1H, furan-CH=C-), 6.85 (d, 2H,
J = 9 Hz, Ar-H), 7.1 (d, 1H, J = 3.6 Hz, Furan-H3), 7.2 (dd, 1H, J = 1.8, 3.6 Hz, Furan-H4),
7.38 (d, 2H, J = 8.1 Hz, Ar-H), 7.42 (d, 2H, J = 9 Hz, Ar-H), 7.73 (d, 2H, J = 7.5 Hz, Ar-H),
7.85 (s, 1H, -NH-NH-), 7.97 (d, J = 1.5 Hz, Furan-H5), 8.57 (s, 1H, -NH-NH-), 10.72 (s, 1H,
-CONHSO2-Ar) ppm.
3
3d
1663(s), 1702(s), 1726(w),
3233(s), 3316(w)
4a
4b
H
1662(s),1699(w), 3112(w),
3263.6(s)
d = 2.38 (s, 3H, Ar-CH ), 6.55 (s, 1H, -CH=C-Ar), 6.70 (dd, 1H, J = 1.8, 3.3 Hz, Furan-H4),
7.06 (s, 1H, furan-CH=C-), 7.15 (d, 1H, J = 3.3 Hz, Furan-H3), 7.30-7.42 (m, 5H, Ph-H), 7.46
(d, 2H, J = 8.4 Hz, Ar-H), 7.69 (d, 2H, J = 8.1 Hz, Ar-H), 7.95 (d, J = 1.5 Hz, Furan-H5),
3
9.32 (s, 1H, NH), 11.49 (s, 1H, -CONHSO -Ar) ppm.
2
CH
1668(s), 1725.8(w), 3099(w),
3266.6(S)
d = 2.35 (s, 3H, Ar-CH ), 2.38 (s, 3H, Ar-CH ), 6.48 (s, 1H, -CH=C-Ar), 6.71 (dd, 1H, J =
3
3 3
1.8, 3.6 Hz, Furan-H4), 6.85 (d, 2H, J = 8.7 Hz, Ar-H), 6.98 (s, 1H, furan-CH=C-), 7.18 (d,
1H, J = 3.6 Hz, furan-H3), 7.36 (d, 2H, J = 8.4, Ar-H), 7.42 (d, 2H, J = 8.7 Hz, Ar-H), 7.68
(d, 2H, J = 8.4 Hz, Ar-H), 7.92 (d, J = 1.5 Hz, furan-H5), 8.32 (s, 1H, NH), 10.49 (s, 1H,
-CONHSO -Ar) ppm.
2
4c
OCH
1679(s), 1737(w), 3214(s),
3376(w)
d = 2.36 (s, 3H, Ar-CH ), 3.78 (s, 3H, Ar-OCH ), 6.46 (s, 1H, -CH=C-Ar), 6.68 (dd, 1H, J =
3
3
3
1.8, 3.3 Hz, Furan-H4), 6.86 (d, 2H, J = 8.7 Hz, Ar-H), 6.99 (s, 1H, furan-CH=C-), 7.1 (d, 1H,
J = 3.3 Hz, furan-H3), 7.35 (d, 2H, J = 8.4 Hz, Ar-H), 7.42 (d, 2H, J = 9 Hz, Ar-H), 7.69 (d,
2H, J = 8.4 Hz, Ar-H), 7.92 (d, J = 1.5 Hz, furan-H5), 8.27 (s, 1H, NH), 10.67 (s, 1H,
-CONHSO -Ar) ppm.
2
4d
5a
5b
5c
5d
Cl
H
1665(s), 1728(w), 3233(s),
3316(w)
d = 2.38 (s, 3H, Ar-CH ), 6.54 (s, 1H, -CH=C-Ar), 6.71 (dd, 1H, J = 1.8, 3.3 Hz, Furan-H4),
6.87 (d, 2H, J = 8.4 Hz, Ar-H), 7.1 (s, 1H, furan-CH=C-), 7.18 (d, 1H, J = 3.3 Hz, furan-H3),
7.37 (d, 2H, J = 8.7 Hz, Ar-H), 7.47 (d, 2H, J = 8.4 Hz, Ar-H), 7.69 (d, 2H, J = 8.1 Hz,
3
Ar-H), 7.95 (d, J = 1.5 Hz, furan-H5), 9.34 (s, 1H, NH), 10.86 (s, 1H, -CONHSO -Ar) ppm.
2
1698.2(s), 1578-1615, 3263
1692(s), 1587-1613, 3216(s)
1692(s), 1589–1610, 3220(s)
1689(s), 1590-1620, 3217(s)
d = 2.38 (s, 3H, Ar-CH ), 4.36 (s, 2H, -CH COPh), 6.66 (dd, 1H, J = 1.8, 3.3 Hz, Furan-H4),
3 2
7.1 (s, 1H, furan-CH=C-), 7.15 (d, 1H, J = 3.3 Hz, Furan-H3), 7.35-7.46 (m, 5H, Ph-H), 7.48
(d, 2H, J = 8.4 Hz, Ar-H), 7.69 (d, 2H, J = 8.4 Hz, Ar-H), 7.95 (d, J = 1.5 Hz, Furan-H5),
11.49 (s, 1H, -CONHSO -Ar) ppm.
2
CH
d = 2.35 (s, 3H, Ar-CH ), 2.38 (s, 3H, Ar-CH ), 4.36 (s, 2H, -CH COAr), 6.67 (dd, 1H, J =
3
3 3 2
1.8, 3.6 Hz, Furan-H4), 6.82 (d, 2H, J = 8.4 Hz, Ar-H), 6.98 (s, 1H, furan-CH=C-), 7.17 (d,
1H, J = 3.3 Hz, furan-H3), 7.35 (d, 2H, J = 8.7, Ar-H), 7.44 (d, 2H, J = 8.4 Hz, Ar-H), 7.67
(d, 2H, J = 8.7 Hz, Ar-H), 7.93 (d, J = 1.5 Hz, furan-H5), 10.49 (s, 1H, -CONHSO -Ar) ppm.
2
OCH
Cl
d = 2.38 (s, 3H, Ar-CH ), 3.81 (s, 3H, Ar-OCH ), 4.47 (s, 2H, -CH COAr), 6.71 (dd, 1H, J =
3
3 3 2
1.8, 3.3 Hz, Furan-H4), 6.87 (d, 2H, J = 8.4 Hz, Ar-H), 7.1 (s, 1H, furan-CH=C-), 7.18 (d, 1H,
J = 3.3 Hz, Furan-H3), 7.37 (d, 2H, J = 8.7 Hz, Ar-H), 7.47 (d, 2H, J = 8.4 Hz, Ar-H), 7.69
(d, 2H, J = 8.7 Hz, Ar-H), 7.95 (d, J = 1.5 Hz, Furan-H5), 10.86 (s, 1H, -CONHSO -Ar) ppm.
2
d = 2.38 (s, 3H, Ar-CH ), 4.47 (s, 2H, -CH COAr), 6.71 (dd, 1H, J = 1.8, 3.3 Hz, Furan-H4),
3
2
6.87 (d, 2H, J = 8.4 Hz, Ar-H), 7.1 (s, 1H, furan-CH=C-), 7.18 (d, 1H, J = 3.3 Hz, Furan-H3),
7.37 (d, 2H, J = 8.7 Hz, Ar-H), 7.47 (d, 2H, J = 8.4 Hz, Ar-H), 7.69 (d, 2H, J = 8.7 Hz,
Ar-H), 7.95 (d, J = 1.5 Hz, Furan-H5), 10.86 (s, 1H, -CONHSO -Ar) ppm.
2
N-{5-[(E)-1-Aroylmethyl-2-(2-furyl)vinyl]-1,3,4-oxadiazol-2-
yl}-p-toluenesulfonamides 5a-d.
rus oxychloride (10 ml) was refluxed for one hour. The mixture
was cooled, poured onto crushed ice (20 ml), neutralized with 1.0
N aqueous solution of sodium hydrogencarbonate. The yellowish
precipitate was collected by filtration, washed with water and
recrystallized from acetonitrile to give 5a-d. Analytical data for
compounds 5a-d are given in Tables 1, 2.
General Procedure D.
A mixture of (E)-2-aroylmethyl-3-(2-furyl)-N2-(tosyl-
aminocarbonyl)acrylohydrazides 3a-d (2 mmoles) and phospho-

1328
A.-S. S. Hamad and A. I. Hashem
Vol. 39
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Acknowledgment.
The authors thank gratefully, Department of Chemistry,
University of Minho, 4710 Braga, Portugal for facilities of
obtained spectral data.
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