Self-assembly molecular complex by 3,6-di(pyridin-4-yl)-1,2,4,5-tetrazine with trimesic acid through H-bonding

Article abstract of DOI:10.1080/15421400600788724

The reaction of 3,6-di(pyridin-4-yl)-1,2,4,5-tetrazine (4-PTA) with trimesic acid (TMA) in methanol solution in a 1.5:1 mole proportion affords molecular complex 1. The structure was confirmed by single crystal X-ray diffraction study. The compound crystallizes in the triclinic space group P-1 with a = 9.7625(11), b = 11.7298(13), c = 13.0734(13), α = 68.849(10)°, β = 72.701(8)°, γ = 83.937(9)° and Z = 2. The crystal structure of 1 shows hydrogen bonding between 4-PTA and TMA, and the presence of an interstitial H₂O molecule in the crystal. The zigzag 1-dimensional framework was constructed by the intermolecular hydrogen bond containing O-H...N, O-H...O and C-H...O interactions. The π-π interactions are the non-covalent forces operating between the pyridine ring in 4-PTA and benzene ring in TMA to generate 3-dimensional network.

Full text of DOI:10.1080/15421400600788724

This article was downloaded by: [Pennsylvania State University]
On: 10 May 2013, At: 10:08
Publisher: Taylor & Francis
Informa Ltd Registered in England and Wales Registered Number: 1072954
Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH,
UK
Molecular Crystals and Liquid
Crystals
Publication details, including instructions for
authors and subscription information:
http://www.tandfonline.com/loi/gmcl20
Self-assembly Molecular
Complex by 3,6-Di(pyridin-4-
yl)-1,2,4,5-tetrazine with
Trimesic Acid through H-
Bonding
Chia-Jung Hsu a , Shang-Wei Tang a , Jau-Shuenn
Wang a & Wen-Jwu Wang a
a Department of Chemistry, Tamkang University,
Tamsui, Taipei, Taiwan (ROC)
Published online: 21 Dec 2006.
To cite this article: Chia-Jung Hsu , Shang-Wei Tang , Jau-Shuenn Wang & Wen-
Jwu Wang (2006): Self-assembly Molecular Complex by 3,6-Di(pyridin-4-yl)-1,2,4,5-
tetrazine with Trimesic Acid through H-Bonding, Molecular Crystals and Liquid
Crystals, 456:1, 201-208
To link to this article: http://dx.doi.org/10.1080/15421400600788724
PLEASE SCROLL DOWN FOR ARTICLE
Full terms and conditions of use: http://www.tandfonline.com/page/terms-
and-conditions
This article may be used for research, teaching, and private study purposes.
Any substantial or systematic reproduction, redistribution, reselling, loan,
sub-licensing, systematic supply, or distribution in any form to anyone is
expressly forbidden.
The publisher does not give any warranty express or implied or make any
representation that the contents will be complete or accurate or up to

date. The accuracy of any instructions, formulae, and drug doses should be
independently verified with primary sources. The publisher shall not be liable
for any loss, actions, claims, proceedings, demand, or costs or damages
whatsoever or howsoever caused arising directly or indirectly in connection
with or arising out of the use of this material.

Mol. Cryst. Liq. Cryst., Vol. 456, pp. 201–208, 2006
Copyright # Taylor & Francis Group, LLC
ISSN: 1542-1406 print=1563-5287 online
DOI: 10.1080/15421400600788724
Self-assembly Molecular Complex by 3,6-Di(pyridin-4-yl)-
1,2,4,5-tetrazine with Trimesic Acid through H-Bonding
Chia-Jung Hsu
Shang-Wei Tang
Jau-Shuenn Wang
Wen-Jwu Wang
Department of Chemistry, Tamkang University,
Tamsui, Taipei, Taiwan (ROC)
The reaction of 3,6-di(pyridin-4-yl)-1,2,4,5-tetrazine (4-PTA) with trimesic acid
(TMA) in methanol solution in a 1.5:1 mole proportion affords molecular
complex 1. The structure was confirmed by single crystal X-ray diffraction study.
The compound crystallizes in the triclinic space group P-1 with a ¼ 9.7625(11),
b ¼ 11.7298(13), c ¼ 13.0734(13), a ¼ 68.849(10)ꢀ, b ¼ 72.701(8)ꢀ, c ¼ 83.937(9)ꢀ
and Z ¼ 2. The crystal structure of 1 shows hydrogen bonding between 4-PTA
and TMA, and the presence of an interstitial H2O molecule in the crystal. The zig-
zag 1-dimensional framework was constructed by the intermolecular hydrogen
bond containing OꢁHꢂ ꢂ ꢂN, OꢁHꢂ ꢂ ꢂO and CꢁHꢂ ꢂ ꢂO interactions. The pꢁp interac-
tions are the non-covalent forces operating between the pyridine ring in 4-PTA and
benzene ring in TMA to generate 3-dimensional network.
Keywords: Hydrogen-bond; multi-compartmental arrays; self-assembly; Trimesic acid;
two-dimensional network; zigzag structure
INTRODUCTION
Solid-state organic and metal-organic systems are of increasing
interest because of their high potential and wide application for
molecular storage, molecular sensing, nano-devices, and catalysis.
Understanding of the relationships between molecular structure and
crystal structure can help develop the tectonic chemistry or crystal
This work was supported by the National Science Council of Taiwan (ROC) and
Tamkang University.
Address correspondence to Wen-Jwu Wang, Department of Chemistry, Tamkang
University, Tamsui 25137, Taipei, Taiwan (ROC). E-mail: wjw@mail.tku.edu.tw
201

202
C.-J. Hsu et al.
engineering, but usually it is very hard to predict molecular packing in
the solid state. For this reason, using the self-assemblying of supra-
molecular systems by chemical forces, like coordination bonding,
hydrogen bonding, pꢁp interactions, p-hydrogen interactions, has
become an area of great interest in crystal engineering for the devel-
opment of tectonic chemistry [1].
Hydrogen bonds play an important role in crystal engineering
because of their selectivity and directionality, which can help control
the design of various molecular assemblies [2]. A judicious choice of
appropriate carboxylic acid donors and pyridine nitrogen acceptors
may form short intermolecular OꢁHꢂ ꢂ ꢂN hydrogen bonds and lead to
different types of molecular architectures [1,3]. The building block con-
taining carboxylic acid group can coordinate with variety of comp-
lementary functional groups. Generally, trimesic acid (TMA) and
pyromellitic acid (PMA) are frequently used as functional building
blocks for the development of tectonic chemistry due to their predict-
able and interesting supramolecular properties. These carboxylic acids
have robust hydrogen bonding abilities and form different types of
CꢁHꢂ ꢂ ꢂO and OꢁHꢂ ꢂ ꢂN hydrogen bonding with the complementary
basic components, such as pyridine, pyrazine, or pyrimidine substi-
tuted molecules, to engineering the desired crystal structures [4–8].
We anticipated that the incorporation of distinctive polycarboxylic-
and dipyridyl- type building blocks within a binary molecular crystal
would lead to formation of new organic crystalline materials with
fascinating supramolecular structures.
Recent studies have focused on hydrogen bonding motifs of
carboxylic acids with complementary functional groups containing
polypyridine as basic unit because of their high success rate [9].
We have already reported the synthesis and crystal structure of
the 3,6-di(pyridin-3-yl)-1,2,4,5-tetrazine (3-PTA) with trimesic acid
(TMA), which forms one-dimensional network and have a chain
saw-like structure. Herein we describe a new tectonic system of
3,6-di(pyridin-4-yl)-1,2,4,5-tetrazine (4-PTA) and its complementary
complex withTMA. We report a detail synthesis, how the molecular
complexes assemble, and what the complementary intermolecular
interactions are.
EXPERIMENTAL
3,6-di(pyridin-4-yl)-1,4-dihydro-1,2,4,5-tetrazine [10]
A mixture of 4-cyanopyridine (10.4 g, 100 mmol, Aldrich, 98%, m.p.78–
80ꢀC) and an excess of hydrazine monohydrate (10 mL, Lancaster,

Self-assembly Molecular Complex
203
98 þ %) were heated in a water bath at 80ꢀC for 3 hr. The solid was
collected and crystallized from ethanol. Orange crystalline needles
were separated on slow evaporation, m.p.240–242ꢀC. The yield was
13.3 g (56%).
3,6-di(pyridin-4-yl)-1,2,4,5-tetrazine(4-PTA) [10]
3,6-Di(pyridin-4-yl)-1,4-dihydro-1,2,4,5-tetrazine (7.0 g, 26 mmol) dis-
solved in a mixture of glacial acetic acid (300 mL) and water
(200 mL) and the solution was cooled to 0ꢀC. Sodium nitrite (9.2 g) in
cold water (25 mL) was then added slowly while vigorously stirring;
the reaction mixture turned into a red-purple color. The mixture
was neutralized with an ice cooled ammonia solution (TEDIA, 28–
30%) and the product was collected by filtration. It was recrystallized
from ethanol. Purplish red plates were formed on slow evaporation,
m.p.261– 262ꢀC. The yield was 6.2 g (90%).
1.5[3,6-di(pyridin-4-yl)-1,2,4,5-tetrazine]?[Trimestic Acid]
(1.5[4-PTA]?[TMA])
Trimestic acid (TMA) and 3,6-di(pyridin-4-yl)-1,2,4,5-tetrazine (4-PTA)
in 1:1.5 molar ratio dissolved in methanol solution. The solution was
then left undisturbed at room temperature for a week. Single X-ray
quality crystals of 1.5[4-PTA]?[TMA] were formed on slow evaporation.
X-ray Structural Study
A colorless single crystal of molecular complex 1(1.5[4-PTA]?[T-
MA]?[2H2O]) was suitable for x-ray analysis. The diffraction data
were collected with Siemens P4 diffractometer using graphite mono-
˚
chromatized Mo–Ka radiation (k ¼ 0.71073A) at 293 K. The unit-cell
parameters were determined from least squares refinements setting
angles of 4930 reflections with 2h in the range 1.86 < 2H < 25ꢀ. The
structure was solved by direct methods using the program SHELXS-97
[11]. The refinement and all other calculations were carried out using
SHELXL-97 [11].
RESULT AND DISCUSSION
The flow chart for synthesis of 4-PTA is presented in Scheme 1.
Samples of 4-cyanopyridine and hydrazine monohydrate were
heated together under reflux to obtain 3,6-di(pyridin-4-yl)-1,4-
dihydro-1,2,4,5-tetrazine. The product was oxidized by nitrous acid

204
C.-J. Hsu et al.
SCHEME 1 Synthetic route used to obtain the 3,6-di(pyridin-4-yl)-1,4-dihydro-
1,2,4,5- tetrazine and 3,6-di(pyridin-4-yl)-1,2,4,5-tetrazine.
TABLE 1 Crystallographic and Structure Refinement Data for Crystal 1 [16]
Formula
C27 H22 N9 O8
600.54
Formula weight
Temperature
Wavelength
Crystal system
Space group
293(2) K
0.71073 A
˚
Triclinic
P-1
˚
˚
A(A)
9.7625(11) A
˚
˚
b(A)
11.7298(13) A
˚
˚
c(A)
13.0734(13) A
a (deg)
b(deg)
c(deg)
68.849(10)
72.701(8)
83.937(9)
1333.1(2)
3
˚
V(A )
Z
2
Absorption coefficient
F(000)
0.114
622
Crystal size
Theta range for data collection
Limiting indices
0.38 ꢃ 0.30 ꢃ 0.18 mm
1.86 to 25.00 deg.
0 < h < 11, ꢁ13 < k < 13, ꢁ14 < l < 15
4930=4630 [R(int) ¼ 0.0264]
98.5%
Reflections collected=unique
Completeness to theta ¼ 25.00
Absorption correction
Max. and min. transmission
Refinement method
Data=restraints=parameters
Goodness-of-fit on F2
Final R indices [I > 2r(I)]
R indices (all data)
Empirical
0.4684 and 0.4480
Full-matrix least-squares on F2
4630=0=477
1.022
R1 ¼ 0.0514, wR2 ¼ 0.1143
R1 ¼ 0.0974, wR2 ¼ 0.1352
ꢁ3
˚
Largest diff. peak and hole
0.244 and ꢁ 0.221 eꢂA

Self-assembly Molecular Complex
205
to 3,6-di(pyridin-4-yl)-1,2,4,5-tetrazine and the pH value was adjusted
to neutral with a solution of ammonia, resulting in the precipitation of
the product. Mixing TMA and 4-PTA (1:1.5 molar ratio) in methanol
solution followed by slow solvent evaporation resulted in colorless
single crystal of molecular complex 1 that were suitable for x-ray
diffraction analysis.
Analysis of the x-ray crystallographic data of molecular complex 1
and the structure refinement parameters are given in Table 1. Selec-
ted bond lengths and bond angles are summarized in Table 2.
Molecular complex 1 crystallizes in the enantiomorphous space
group P–1. The molecular structure of 1 is shown in Figure 1. During
refinement it was observed that O8 atom of the water molecule was
disordered. It was difficult to refine the closely connected hydrogen
atoms, suggesting that there are very weak interactions around the
H2O. The two-dimensional structure of 1 is given in Figure 2.
The 4-PTA molecule is linked with TMA and H2O based on
OꢁHꢂ ꢂ ꢂN, OꢁHꢂ ꢂ ꢂO hydrogen bonds. The two pyridine groups of
4-PTA are interconnected with TMA by intermolecular O3ꢁH31ꢂ ꢂ ꢂN7
and O6ꢁH6Oꢂ ꢂ ꢂN1 hydrogen bonding with angles 176(3)ꢀ and
171(4)ꢀ. Besides this, 4-PTA is also interconnected with H2O by
intermolecular O7ꢁH7OAꢂ ꢂ ꢂN6 hydrogen bonding with angles
169(4)ꢀ generating one-dimensional infinite chain structure. TMA
˚
TABLE 2 Selection Bond Lengths [A] and Angles [deg] for Crystal 1
O1ꢁC7
1.320(3)
1.205(3)
1.284(3)
1.220(3)
1.206(3)
1.314(3)
1.325(3)
1.314(3)
1.321(3)
1.338(3)
1.338(3)
117.1(3)
117.8(2)
117.3(2)
117.6(2)
117.8(2)
116.6(3)
119.2(2)
117.9(2)
123.8(2)
O1ꢁC7ꢁC1
112.4(2)
120.7(2)
116.1(2)
122.7(3)
123.4(2)
123.7(3)
123.7(3)
124.5(2)
118.4(2)
117.1(2)
124.6(2)
118.3(2)
117.1(2)
123.4(3)
124.2(3)
121.9(3)
122.3(3)
124.8(2)
117.7(2)
117.5(2)
O2ꢁC7
O4ꢁC8ꢁC3
O3ꢁC8
O3ꢁC8ꢁC3
O4ꢁC8
O5ꢁC9ꢁO6
O5ꢁC9
O5ꢁC9ꢁC5
O6ꢁC9
N1ꢁC10ꢁC11
N1ꢁC14ꢁC13
N2ꢁC15ꢁN4
N2ꢁC15ꢁC12
N4ꢁC15ꢁC12
N3ꢁC16ꢁN5
N3ꢁC16ꢁC19
N5ꢁC16ꢁC19
N6ꢁC17ꢁC18
N6ꢁC21ꢁC20
N7ꢁC22ꢁC23
N7ꢁC26ꢁC25
N8ꢁC27ꢁN9
N8ꢁC27ꢁC24
N9ꢁC27ꢁC24
N2ꢁN3
N4ꢁN5
N8ꢁN9
N8ꢁC27
N9ꢁC27
C10ꢁN1ꢁC14
N3ꢁN2ꢁC15
N2ꢁN3ꢁC16
N5ꢁN4ꢁC15
N4ꢁN5ꢁC16
C21ꢁN6ꢁC17
C26ꢁN7ꢁC22
N9ꢁN8ꢁC27
O2ꢁC7ꢁC1

206
C.-J. Hsu et al.
FIGURE 1 ORTEP diagram of molecular complex 1, hydrogen atoms are
omitted for clarity.
is also interconnected with H2O provided intermolecular O7ꢀ
H7OBꢁ ꢁ ꢁO4 and O1ꢀH1Oꢁ ꢁ ꢁO7 hydrogen bonding with angles 171(4)ꢂ
and 161(4)ꢂ, forming a two-dimensional framework. The 4-PTA
is also linked with TMA and H2O by CꢀHꢁ ꢁ ꢁO hydogen bonds. Selec-
ted hydrogen bond distances and bond angles are summarized in
Table 3.
In the literature reported so far, the structure formed by the reac-
tion of 4,40 -bipyridine with TMA appeared as 3-fold interweaving
(6,3) networks with parallel interpenetration [12–14] and the struc-
ture formed by the reaction of 2[3,6-bis(pyridin-3-yl)-1,2,4,5-tetrazine]
with TMA [15] formed a chain saw-like molecular complex. The
FIGURE 2 Two-dimensional structure of molecular complex 1.

Self-assembly Molecular Complex
207
TABLE 3 Analysis of Potential Hydrogen Bond Lengths and Bond Angles
DꢀHꢁ ꢁ ꢁA
DꢀH
Hꢁ ꢁ ꢁA
DꢀA
Deg.
O7ꢀH7OBꢁ ꢁ ꢁO4vi
O1ꢀH1Oꢁ ꢁ ꢁO7iv
O7ꢀH7OAꢁ ꢁ ꢁN6iv
O6ꢀH6Oꢁ ꢁ ꢁN1iii
O3ꢀH31ꢁ ꢁ ꢁN7i
O4ꢀH31ꢁ ꢁ ꢁN7i
C2ꢀH2ꢁ ꢁ ꢁO3
0.99(5)
0.83(5)
0.84(5)
0.95(5)
1.31(4)
1.31(4)
0.88(2)
0.95(2)
1.04(4)
0.88(3)
0.97(3)
1.00(4)
0.92(4)
1.75(5)
1.76(5)
1.96(5)
1.69(5)
1.28(5)
2.41(4)
2.51(2)
2.38(2)
2.54(4)
2.52(3)
2.46(4)
2.46(4)
2.48(4)
2.722(3)
2.552(3)
2.782(3)
2.631(3)
2.589(3)
3.245(3)
2.793(3)
2.756(3)
3.343(4)
2.827(4)
3.134(4)
3.350(5)
3.384(4)
171(4)
161(4)
169(4)
171(4)
176(3)
119(3)
100.01(18)
103.1(17)
133(3)
C6ꢀH6ꢁ ꢁ ꢁO6
C17ꢀH17ꢁ ꢁ ꢁO1
C20ꢀH20ꢁ ꢁ ꢁN3
C21ꢀH21ꢁ ꢁ ꢁO5v
C22ꢀH22ꢁ ꢁ ꢁO8
C23ꢀH23ꢁ ꢁ ꢁO8ii
101(2)
126(2)
148(3)
171(3)
Symmetry codes: (i) x,1 þ y, ꢀ1 þ z, (ii) ꢀx,1 ꢀy,1 ꢀz, (iii) 1 ꢀx,1 ꢀy, ꢀz, (iv) 1 ꢀx,
1 ꢀy,1 ꢀz, (v) x,1+y,z, (vi) 1 ꢀx, ꢀy,1 ꢀz.
molecular complex 1 exhibits atwo-dimensional zigzag network. This
type of network is due to the presence of complementary H2O molecule
in the crystals that interconnect the 4-PTA and TMA. The molecular
packing diagram is shown in Figure 3.
The pyridine ring in 4-PTA and benzene ring in TMA contribute
weak edge-to-edge pꢀp interaction to support 3-dimensional crystal
FIGURE 3 Packing diagrams of molecular complex 1 between layer 1 and
layer 2 (left) and layer 2 and layer 3 (right). Hydrogen atoms are omitted for
clarity.

208
C.-J. Hsu et al.
packing. The distance between two closely layers [N6 to C22] and [C21
˚
˚
to C23] are 3.5(5)A and 3.7(4)A), respectively.
CONCLUSION
In this work we present the synthesis of 4-PTA and the single crystal
X-ray structure of molecular complex 1. It forms zigzag supramolecu-
lar architecture using intermolecular hydrogen bonding between the
4-PTA, TMA and H2O.
REFERENCES
[1] Christer, B. A., Alicia, M. B., & Brian, A. H. (2002). Angew. Chem. Int. Ed., 41(17),
3240.
[2] Steiner, T. (2002). Angew. Chem. Int. Ed., 41(1), 48.
[3] Miao, D. M., Zhang, Z. H., & Zhao, X. J. (2005). Cryst. Growth Des., 5(3), 1247.
[4] Shan, N., Bond, A. D., & Jones, W. (2002). Cryst. Eng., 5(1), 9.
[5] Pedireddi, V. R., Chatterjee, S., Ranganathan, A., & Rao, C. N. R. (1997). J. Am.
Chem. Soc., 119, 10867.
[6] Pedireddi, V. R., Ranganathan, A., & Chatterjee, S. (1998). Tetra. Lett., 39, 9831.
[7] Moulton, B. & Zaworotko, M. J. (2001). Chem. Rev., 101, 1629.
[8] Lough, A. J., Wheatley, P. S., Ferguson, G., & Glidewell, C. (2000). Acta Cryst., B56,
261.
[9] Steiner, T. (2001). Acta Cryst., B57, 103.
[10] Geldard, J. F. & Francis, L. (1965). J. Org. Chem., 30, 318.
[11] Sheldrick, G. M. (1997). SHELEXS97 and SHELXL97. University of Gotengen:
Germany.
[12] Sharma, C. V. K. & Zaworotko, M. J. (1996). Chem. Commun., 23, 2655.
[13] Bhogala, B. R., Vishweshwar, P., & Nangia, A. (2002). Cryst. Growth Des., 2(5), 325.
[14] Bhogala, B. R. & Nangia, A. (2003). Cryst. Growth Des., 3(4), 547.
[15] Wang, W. J. & Wang, J. S. (2005). Mol. Cryst. Liq. Cryst., 440, 147.
[16] CCDC 284425 contains the supplementary crystallographic data for this paper.
These data can be obtained free of charge from The Cambridge Crystallographic
Data Centre via www.ccdc.cam.ac.uk/data_request=cif. The Cambridge Crystallo-
graphic Data Centre, 12 Union Road, Cambridge, CB2 1EZ, UK, þ 44 1223
336408. Hydrogen atoms are omitted for clarity.