Synthesis and reactions of some 1,2,4-triazolo-[4,3-b]-1,2,4-triazoles

Article abstract of DOI:10.1081/SCC-100105123

Reaction of 5-aryl-3-chloro-4-phenyl-1,2,4-triazoles (1 & 2) with hydrazine hydrate afforded the hydrazino derivatives 3 and 4. Reaction of 3 and 4 with carboxylic acids, CS₂ and phenylisothiocyanate gave the s-triazole-fused ring systems 5-12. On the other hand, reaction of 3 and 4 with nitrous acid gave tetrazole-fused ring systems 13 and 14, respectively. Mannich reaction on compounds 9 and 10 afforded Mannich bases 15 and 16.

Full text of DOI:10.1081/SCC-100105123

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SYNTHESIS AND REACTIONS OF SOME 1,2,4-
TRIAZOLO-[4,3-b]-1,2,4-TRIAZOLES
A.-B. A. G. Ghattas a , H. M. Moustafa b , O. A. Abd Allah a & A. A. Amer a
a Chemistry Department, Faculty of Science, South Valley University, Sohag, Egypt
b Chemistry Department, Faculty of Science, South Valley University, Sohag, Egypt
Version of record first published: 09 Nov 2006.
To cite this article: A.-B. A. G. Ghattas , H. M. Moustafa , O. A. Abd Allah & A. A. Amer (2001): SYNTHESIS AND
REACTIONS OF SOME 1,2,4-TRIAZOLO-[4,3-b]-1,2,4-TRIAZOLES, Synthetic Communications: An International Journal for
Rapid Communication of Synthetic Organic Chemistry, 31:16, 2447-2456
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SYNTHETIC COMMUNICATIONS, 31(16), 2447–2456 (2001)
SYNTHESIS AND REACTIONS OF SOME
1,2,4-TRIAZOLO-[4,3-b]-1,2,4-TRIAZOLES
A.-B. A. G. Ghattas, H. M. Moustafa,*
O. A. Abd Allah, and A. A. Amer
Chemistry Department, Faculty of Science,
South Valley University, Sohag, Egypt
ABSTRACT
Reaction of 5-aryl-3-chloro-4-phenyl-1,2,4-triazoles (1 & 2)
with hydrazine hydrate afforded the hydrazino derivatives 3
and 4. Reaction of 3 and 4 with carboxylic acids, CS2 and
phenylisothiocyanate gave the s-triazole-fused ring systems
5–12. On the other hand, reaction of 3 and 4 with nitrous
acid gave tetrazole-fused ring systems 13 and 14, respectively.
Mannich reaction on compounds 9 and 10 afforded Mannich
bases 15 and 16.
Certain compounds containing 1,2,4-triazole nucleus have been
reported to possess fungicidal,1,2 insecticidal,3 antimicrobial,4,5 bacterici-
dal,6 and antiviral7 activity. Also, some triazole derivatives have been
synthesized as anticonvulsants,8,9 and plant growth regulators.10 The pres-
ent work aims to synthesize a special group of heterocyclic compounds in
which the 1,2,4-triazole nucleus is fused with other heterocyclic rings, which
may exert some reasonable biological activity.
*Corresponding author.
2447
Copyright & 2001 by Marcel Dekker, Inc.
www.dekker.com

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GHATTAS ET AL.
RESULTS AND DISCUSSION
The starting materials 4,5-diphenyl- and 4-phenyl-5-(4-chloro-phenyl)-
3-chloro-1,2,4-triazoles (1 & 2) were prepared by oxidative chlorination
of the corresponding 3-mercapto-derivatives using the method of
Deshpande et al.11
The chemical structure of the new compound 2 was confirmed by
elemental and spectral analyses.
The starting triazoles 3 and 4 were prepared by refluxing 3-chloro-
derivatives (1 & 2) with excess of hydrazine hydrate 98% in ethanol.
Treatment of compounds 3 and 4 with aromatic acids furnished the
corresponding 1,2,4-triazolo[4,3-b]-1,2,4-triazoles 5 and 6, respectively. The
structure of these products was confirmed using elemental and spectral
analyses (cf Table).
Compounds 3 and 4 underwent readily ring closure with formic
acid and acetic acid to give 1,2,4-triazolo[4,3-b]-1,2,4-triazoles 7 and 8.

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1,2,4-TRIAZOLO-[4,3-b]-1,2,4-TRIAZOLES
2449
Table. Analytical and Spectral Data of the Prepared Compounds
Comp.
No.
M.p.
Yield
(%)
MF
Analytical data Calc. (Found) (%)
Cryst. Solv
(MW)
C
H
N
2
3
196 Ethanol
167 Ethanol
80
70
C
C
C
14H9N3Cl2 (290)
14H13N5 (251)
57.93 (58.29) 3.10 (2.84) 14.48 (14.17)
66.93 (66.65) 5.18 (4.89) 27.89 (27.60)
58.84 (59.51) 4.20 (3.90) 24.52 (24.81)
67.83 (67.49) 3.77 (4.06) 18.84 (18.52)
71.39 (71.72) 4.25 (3.97) 19.83 (19.41)
65.97 (65.64) 3.67 (3.29) 21.99 (21.68)
75.21 (75.70) 4.84 (5.07) 19.94 (19.44)
62.07 (61.75) 3.20 (3.01) 17.24 (16.88)
65.03 (64.87) 3.61 (3.34) 18.07 (17.59)
4207 Ethanol
72
14H12N5Cl (285.5)
5a
5b
5c
5d
6a
6b
6c
6d
7a
7b
8a
8b
9
119 Ethanol
105 Ethanol
173 Ethanol
100 Ethanol
130 Ethanol
126 Ethanol
110 Ethanol
195 Ethanol
59
50
48
62
60
47
42
67
65
61
64C
57
65
60
43
49
80
C21H14N5Cl (371.5)
C21H15N5O (353)
C21H14N6O2 (382)
C22H17N5 (351)
C21H13N5Cl2 (406)
C21H14N5OCl (387.5)
C21H13N6O2Cl (416.5) 60.50 (60.82) 3.12 (2.87) 20.17 (19.89)
C22H16N5Cl (385.5)
C15H11N5 (261)
68.48 (68.86) 4.15 (4.52) 18.16 (17.87)
68.97 (68.54) 4.22 (4.42) 26.82 (26.51)
69.82 (69.51) 4.73 (5.04) 25.46 (25.19)
60.91 (60.58) 3.38 (3.11) 23.69 (23.25)
62.04(62.45) 3.88 (3.56) 22.62 (22.93)
61.43 (61.83) 3.75 (3.40) 23.89 (23.47)
54.96 (54.62) 3.05 (2.68) 21.37 (21.04)
71.59 (71.98) 4.55 (4.94) 23.86 (23.43)
65.20 (65.61) 3.88 (3.59) 21.73 (22.11)
64.12 (64.51) 3.82 (3.46) 32.06 (31.74)
56.66 (57.13) 3.04(3.45) 28.33 (28.06)
61.23 (61.58) 5.10 (4.80) 21.43 (21.07)
155 Acetic acid
135 Ethanol
225 Acetic acid
160 Ethanol
259 Ethanol
274Ethanol
C16H13N5 (275)
15H10N5Cl (295.5)
C16H12N5Cl (309.5)
C
15H11N5S (293)
15H10N5SCl (327.5)
21H16N6 (352)
10
11
12
13
C
175 Ethanol
98 Ethanol
C
C
C
21H15N6Cl (386.5)
14H10N6 (262)
145 Ethanol
14129 Ethanol
74C
14H9N6Cl (296.5)
15a
15b
236 Benzene
80
C20H20N6OS (392)
141 (Pet. Ether
60–80)
65
C
20H22N6S (378)
63.49 (63.96) 5.82 (5.51) 22.22 (22.53)
66.99 (66.49) 4.85 (4.56) 20.39 (20.07)
63.16 (63.63) 4.26 (3.98) 24.56 (24.84)
65.46 (65.16) 4.55 (4.22) 19.09 (18.87)
15c
15d
15e
16a
16b
16c
16d
16e
124Cyclohexan
138 Cyclohexan
120 Cyclohexan
138 Ethanol
64
C 23H20N6S (412)
67
C21H17N7S (399)
60
C24H20N6OS (440)
74C
70
20H19N6OSCl (426.5) 56.27 (56.75) 4.46 (4.17) 19.70 (19.36)
110 Benzene
97 Benzene
C20H21NSCl (412.5)
C23H19N6SCl (446.5)
C21H16N7SCl (433.5)
58.18 (58.49) 5.09 (5.41) 20.36 (20.01)
61.81 (62.24) 4.26 (4.58) 18.81 (18.54)
58.13 (58.64) 3.69 (3.38) 22.61 (22.47)
82
93 Cyclohexan
109 Cyclohexan
62
60
C24H19N6SOCl (474.5) 60.70 (60.31) 4.00 (4.32) 17.70 (17.35)
(continued)
The elemental and spectral analyses of these compounds were in agreement
with their structures (cf Table).
Reaction of compounds 3 and 4 with CS2 in ethanolic potassium
hydroxide afforded 3-mercapto-1,2,4-triazolo[4,3-b]-1,2,4-triazoles 9 and
10, respectively.

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GHATTAS ET AL.
Table. Continued
Comp.
No.
IR (KBr)
ꢀ (cmꢀ1
1H-NMR d (ppm)
(a, CDCl3; b, DMSO)
)
2
3
698 (C–Cl).
3412, 3225, 3217.7 (NH2þNH).
7.8–7.3 (m, 4H, arom.).a
8.0–7.4(br, 10H, arom. þ NH),
3.6 (br, 2H, NH2).a
124.53,43337, 325 (NH
2þNH).
10.8–10.6 (br, 1H, NH),
4.3 (br, 2H, NH2).a
5a
5b
765 (C–Cl).
7.7–7.1 (m, 14H, arom.).a
3425–3209 (OH).
7.8–7.1 (m, 14H, arom.);
2.2 (s, 1H, OH).a
5c
1523, 1334(NO ).
2
8.1–7.0 (m, 14H, arom.).a
5d
2960 (CH, aliph.).
7.7–7.2 (m, 14H, arom.);
2.1 (s, 3H, CH3).a
6a
6b
800 (C–Cl).
7.6–7.1 (m, 13H, arom.).a
3450–3300 (OH).
7.7–7.1 (m, 13H, arom.);
2.2 (s, 1H, OH).a
6c
1520, 1300 (NO2).
2940 (CH, aliph.).
8.2–7.2 (m, 13H, arom.).a
6d
7.7–7.2 (m, 13H, arom.);
2.3 (s, 3H, CH3).a
7a
7b
8a
8b
9
1603 (C ¼ N).
8.9 (s, 1H, ¼ CH);
7.7–7.2 (m, 10H, arom.).a
2913 (CH, aliph.), 1618 (C ¼ N).
1611 (C ¼ N).
7.7–7.2 (m, 10H, arom.);
2.2 (s, 3H, CH3).a
8.9 (s, 1H, ¼ CH);
7.7–7.2 (m, 9H, arom.).a
2909 (CH, aliph.), 1601 (C ¼ N).
7.7–7.2 (m, 9H, arom.);
2.2 (s, 3H, CH3).a
3420 (NH), 2764 (SH),
1186 (C ¼ S)
11.5 (br, 0.6H, NH), 7.8–7.1
(m, 10H, arom), 3.1 (s, 0.4H, SH).b
10
3420 (NH), 2764 (SH),
11.5 (br, 0.65H, NH), 7.8–7.1
(m, 9H, arom.), 3.2 (s, 0.35H, SH).b
8.0–7.1 (m, 16H, arom. þ NH).b
8.0–7.1 (m, 15H, arom. þ NH).b
7.9–7.3 (m, 10H, arom.).a
1186 (C ¼ S).
11
12
13
3420 (NH).
3420 (NH).
1612 (C ¼ N).
141607 (C
¼ N).
7.8–7.2 (m, 9H, arom.).a
(continued)

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1,2,4-TRIAZOLO-[4,3-b]-1,2,4-TRIAZOLES
Table. Continued
7.7–7.3 (m, 10H, arom.);
2451
15a
2961, 2870 (CH, aliph.),
1179 (C ¼ S).
5.2 (s, 2H, NCH2N);
3.9–3.5 (m, 4H, CH2OCH2);
3.0–2.8 (m, 4H, CH2NCH2).a
15b
2980, 2888 (CH, aliph.),
1170 (C ¼ S).
7.7–7.2 (m, 10H, arom.);
5.2 (s, 2H, NCH2N);
3.7–3.2 (q, 4H, 2CH2);
1.4–1.0 (t, 6H, 2CH3).a
15c
15d
15e
16a
2969 (CH2 aliph.), 1190 (C ¼ S).
7.8–7.0 (m, 16H, arom.þNH);
5.8 (s, 2H, NCH2N);
4.0–3.8 (d, 2H, CH2Ph).a
2988 (CH, aliph.),
1177 (C ¼ S).
8.2 (S, 1H, NH);
7.7–7.2 (m, 14H, arom.);
5.8 (s, 2H, CH2).a
2969 (CH, aliph.), 1690
(C ¼ O), 1187 (C ¼ S).
7.9–7.0 (m, 14H, arom.);
6.3 (S, 1H, NH); 5.8 (s, 2H, CH2);
2.5 (S, 3H, CH3).a
2961, 2869 (CH, aliph),
1183 (C ¼ S).
7.7–7.3 (m, 9H, arom.);
5.2 (s, 2H, NCH2N);
3.9–3.5 (m, 4H, CH2OCH2);
3.0–2.8 (m, 4H, CH2NCH2).a
16b
2963, 2889 (CH, aliph.),
1176 (C ¼ S).
7.9–7.2 (m, 9H, arom.);
5.3 (s, 2H, NCH2N);
3.5–3.0 (q, 4H, 2CH2);
1.8–1.0 (t, 6H, 2CH3).a
16c
16d
16e
2967 (CH, aliph.), 1181 (C ¼ S).
2987 (CH, aliph.), 1189 (C ¼ S).
7.8–7.1 (m, 15H, arom.þNH);
5.8 (s, 2H, NCH2N);
3.8–3.4(d, 2H, CH 2Ph).a
8.9 (S, 1H, NH);
8.5–7.2 (m, 13H, arom.);
5.2 (s. 2H, CH2).a
2961 (CH, aliph.), 1687
(C ¼ O), 1183 (C ¼ S).
7.9–7.0 (m, 13H, arom.);
6.0 (S, 1H, NH); 5.3 (s, 2H, CH2);
2.5 (S, 3H, CH3).a
The elemental and spectral analyses of these compounds were in agree-
ment with their structures.
Refluxing compound 3 with phenylisothiocyanate in dry pyridine
for 20 h gave a mixture of triazolo[4,3-b]-1,2,4-triazoles 9 and 11, which
was separated by aq. sodium hydroxide solution. This reaction presumably

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2452
GHATTAS ET AL.
proceeds through the initial formation of the corresponding phenylthiourea
intermediate and subsequent elimination of hydrogen sulphide to give 11 as
a major product or elimination of aniline to give 9 as a minor product.
Likewise, when compound 4 was refluxed with phenylisothiocyanate, it
gave a mixture of triazolo[4,3-b]-1,2,4-triazoles 10 and 12 which was sepa-
rated by the same method.
The structure of the products 9 and 10 was confirmed by the direct
comparison (m.p. and mixed m.p.) with those obtained by the reaction of the
corresponding hydrazino derivatives 3 and 4 with CS2/KOH. The elemental

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1,2,4-TRIAZOLO-[4,3-b]-1,2,4-TRIAZOLES
2453
and spectral analyses of compounds 11 and 12 were in agreement with their
structures (cf. Table).
Treatment of compounds 3 and 4 with nitrous acid gave 1,2,4-tria-
zolo[1,5-d]tetrazoles 13 and 14, respectively.
The structure of products 13 and 14 was confirmed using elemental
and spectral analyses (cf Table). The mass spectrum of 13 showed the
following fragmentation pattern m/e (rel. intensity %): 262 (M, 98.56),
235 (15.46), 220 (13.35), 207 (22.12), 180 (89.75), 103 (60.43), 77 (91).
When compound 9 and 10 were subjected to Mannich reaction using
morpholine, diethylamine, benzylamine, 3-aminopyridine and p-aminoace-
tophenone, the corresponding Mannich bases 15a–e and 16a–e were
obtained.
Elemental and spectral analyses of products 15 and 16 are consistent
with their structures (cf. Table). The mass spectrum of compound 15a
showed the following fragmentation pattern m/e (rel. intensity %) 392
(5.56), 293 (11.29), 180 (4.83), 100 (100), 77 (17.45), 70 (3.82).

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2454
GHATTAS ET AL.
EXPERIMENTAL
Melting points are uncorrected and were determined on Kofler
melting point apparatus. IR (cmꢀ1) spectra were obtained (KBr disc) on
1
Nicolet 710 FT-IR Spectrophotometer. H-NMR spectra were recorded at
60 MHz on Varian EM 360 L Spectrometer. The chemical shift are expressed
in d values (ppm) TMS was used as internal reference. The MS were
recorded on a Micromass 7070 E Spectrometer operating at 70 ev, using
direct inlet. Elemental analyses were carried out on an elemental analyzer
240 C.
Preparation of
3-chloro-5-(4-chlorophenyl)-4-phenyl-1, 2,4-triazole (2)
A slow stream of dry chlorine gas was passed through a suspension of
3-mercapto-5-(4-chlorophenyl)-4-phenyl-1,2,4-triazole (5.75 g, 0.02 mol) in
dry chloroform (150 mL) within 15 min the whole material dissolved.
Chlorine gas was passed for a further period of 40 min and the reaction
mixture was washed thoroughly with dil. alkali (2% NaOH) and then
with water (4times). The chloroform layer was dried (Na 2SO4) and evapo-
rated to give compound 2 (cf. Table).
Preparation of 4,5-diphenyl- and 5-(4-chlorophenyl)-4-phenyl-3-
hydrazino-1,2,4-triazoles(3 & 4)
General Procedure
A solution of compound 1 or 2 (0.023 mol) and hydrazine hydrate
99% (10 mL) in ethanol (10 mL) was refluxed for 5 h. On cooling the solid
product was filtered off and recrystallized from the proper solvent
(cf. Table).
Synthesis of 6,7-diphenyl- and 6-(4-chlorophenyl)-7-phenyl-3-aryl-
1,2,4-triazolo[4,3-b]-1,2,4-triazoles(5a–e & 6a–e)
General Procedure
A mixture of 3 and/or 4 (0.004mol) and an aromatic acid: 4-hydroxy-
benzoic acid, p-toluic acid, 4-chlorobenzoic acid, and/or 4-nitrobenzoic acid
(0.004mol) was refluxed in methanol (10 mL) for 9 h. Excess solvent was

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1,2,4-TRIAZOLO-[4,3-b]-1,2,4-TRIAZOLES
2455
removed and the residue poured onto crushed ice. The solid thus separated
was washed with 10% sodium bicarbonate solution and recrystallized from
the proper solvent (cf. Table).
Synthesis of 6,7-diphenyl- and 6-(4-chlorophenyl)-7-phenyl-1,2,4-
triazolo-[4,3-b]-1,2,4-triazoles(7a & 8a)
General Procedure
A mixture of 3 and/or 4 (0.002 mol) and formic acid (10 mL) was
refluxed for 5 h. After cooling the reaction mixture was poured onto crushed
ice. The obtained solid was filtered off then recrystallized from the proper
solvent (cf. Table).
Synthesis of 6,7-diphenyl- and 6-(4-chlorophenyl)-7-phenyl-3-methyl-
1,2,4-triazolo[4,3-b]-1,2,4-triazoles(7b & 8b)
General Procedure
A mixture of 3 and/or 4 (0.004mol) and acetic acid (15 mL) was
refluxed for 6 h. After cooling the reaction mixture was poured onto crushed
ice. The obtained solid was filtered off then recrystallized from the proper
solvent (cf. Table).
Synthesis of 6,7-diphenyl- and 6-(4-chlorophenyl)-7-phenyl-3-
mercapto-1,2,4-triazolo[4,3-b]-1,2,4-triazoles(9 & 10)
General Procedure
A mixture of 3 and/or 4 (0.02 mol), KOH (0.025 mol), ethanol (95%,
60 mL) and CS2 (0.04mol) was refluxed for 14h and the alkaline solution
was filtered. After precipitation with dilute hydrochloric acid, the crude
product was filtered off then recrystallized from the proper solvent
(cf. Table).
Synthesis of 6,7-diphenyl- and 6-(4-chlorophenyl)-7-phenyl-3-phenyl-
amino-1,2,4-triazolo[4,3-b]-1,2,4-triazoles(11 & 12)
General Procedure
To a solution of 3 and/or 4 (0.007 mol) in pyridine was added pheny-
lisothiocyanate (0.007 mol) and the solution was heated under reflux for

ORDER
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2456
GHATTAS ET AL.
20 h, concentrated and poured into water, the precipitate was filtered off and
recrystallized from ethanol to give a mixture of 9 and 11 or 10 and 12. The
mixture was separated by stirring for 30 min with dil. alkali (2% NaOH) and
filtered. The filtrate was acidified with dilute HCl to give 9 or 10 in 29% and
24% yield, respectively and the precipitate washed with water (5 times),
filtered off and recrystallized from ethanol to give 11 or 12 in 43% and
49% yield, respectively.
Synthesis of 6,7-diphenyl- and 6-(4-chlorophenyl)-7-phenyl-1,
2,4-triazole-[1,5-d]tetrazoles(13 & 14)
General Procedure
To a solution of 3 and/or 4 (0.004mol) in conc. Hydrochloric acid
(20 mL), sodium nitrite solution (30 mL, 5%) was added dropwise at 0ꢁC for
40 minutes with stirring. The solid product was filtered off and washed with
water and recrystallized from the proper solvent (cf. Table).
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Received in the USA November 10, 2000

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