A thirty-membered macrocyclic binuclear metal complex: Synthesis and structural characterization of [Ag2(psb)2]2+ {psb = 1,2-bis[(4-pyridyl)sulfanylmethyl]benzene}

Article abstract of DOI:10.1246/cl.2000.28

A neutral exo-pyridino-bidentate ligand, 1,2-bis[(4-pyridyl)sulfanylmethyl]benzene (psb), was prepared from the reaction of 1,2-bis(bromomethyl)benzene and sodium pyridine-4-thiolate for metal complex syntheses. The reaction of silver salt and psb resulte

Full text of DOI:10.1246/cl.2000.28

28
Chemistry Letters 2000
A Thirty-Membered Macrocyclic Binuclear Metal Complex: Synthesis and Structural
Characterization of [Ag2(psb)2]2+ {psb = 1,2-Bis[(4-pyridyl)sulfanylmethyl]benzene}
Yingjun Zhao, Maochun Hong,* Weiping Su, Rong Cao,* Zhongyong Zhou,† and Albert S. C. Chan*†
State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of
Sciences, Fuzhou, Fujian 350002, P R. China
†Department of Applied Biology and Chemical Technology, The Hong Kong Polytechniqic University,
Hong Hom, Hong Kong, PR. China
(Received September 6, 1999; CL-9900768)
complexing ability,10 the sulfur atom of the thioether may act
as no coordination donor. Due to the behavior of the exo-
bidentate ligand of pyridine group11 along with the o-xylyl
spacer, the N atoms of the two 2-thiopyridine groups can only
bond to different metal atoms. Therefore, psb may be a biden-
tate but nonchelating ligand, and able to bridge two metal
atoms in specific directions.
A neutral exo-pyridino-bidentate ligand, 1,2-bis[(4-
pyridyl)sulfanylmethyl]benzene (psb), was prepared from the
reaction of 1,2-bis(bromomethyl)benzene and sodium pyridine-
4-thiolate for metal complex syntheses. The reaction of silver
salt and psb resulted in binuclear complex [Ag2(psb)2](ClO4)2
with a thirty-membered macrocycle, in which the length is
2.0 nm.
Design and research of discrete macrocycles and cages are
a subject of great interest in the supramolecular chemistry.1-3
The potential use of this kind of compound largely depends on
their cavity size and type, which are controlled by the ligands.
Therefore, the design of ligands is crucial to the constructions
of specific supramolecular architectures.4-6 For instances,
triple helicate tetrahedral cluster cage can be obtained by the
self-assembly reaction of bis(bidentate)catecholamide and
metal ions.7 The treatment of [Pd(NO3)2(en)] with 2,4,6-tri(4-
pyridyl)-1,3,5-triazine resulted in a molecular cage,1 while the
similar reaction with 2,4,6-tri(3-pyridyl)-1,3,5-triazine in place
of 2,4,6-tri(4-pyridyl)-1,3,5-triazine led to a bowl-like
The complex [Ag2(psb)2](ClO4)2 was obtained from the
reaction of AgClO4 with psb in a metal-to-ligand ratio of 1 : 1
in DMF/MeCN, respectively. To a solution of AgClO4 (0.11 g,
0.5 mmol) in DMF a solution of the ligand psb (0.32 g, 1
mmol) in acetonitrile (10 ml) was added. The reaction mixture
was stirred for 3 h. The resulting solution is filtered and the fil-
trate was slowly diffused by ether to give a large amount of
colorless block crystals of the complex.
3b
macrotricycle.3
In our previous studies, we used some simple ligands con-
taining both sulfur and nitrogen donors, such as pyridine-2-thi-
olate, pyrimidine-2-thiolate, pyridine-2-thione, and 2-mercap-
toethylamine, and obtained a series of complex polymers with
linear chain or 3-D network structures.8 Considering the fact
that a little information is contained in the ligands we used, we
carefully examined the geometric requirements of particular
symmetry and stereochemitry, and began to design ligands
containing more information, expecting to obtain metal com-
plexes with novel structures.9 Herein, we report a neutral exo-
pyridino-bidentate ligand 1,2-bis[(4-pyridinyl) sulfanyl-
methyl]benzene(psb), which contains two 4-thiopyrimidine
groups separated by an o-xylyl spacer, and metal complex with
a thirty-membered macrocycle [Ag2(psb)2](ClO4)2 prepared
from silver salt with the ligand psb.
Single-crystal X-ray diffraction analyses of the complex
were carried out.12 Crystal data: Crystal dimensions 0.16 x
0.14 x 0.10 mm, Formula C36H32N4Ag2Cl2S4O8, Fw 1063.54,
triclinic, space group P1, a = 8.1587(14) Å, b = 8.4447(14) Å,
c = 14.745(3) Å, α = 87.307(3)°, β = 82.638(3)°, γ =
72.716(3)°, V= 962.0(3) Å3, Z= 1, R(wR)=0.0347(0.0961) for
5229 reflections with F ≥ 2.0 σ(Fo). The crystallographic
analyses revealed that the cation is a binuclear complex with a
thirty-membered macrocycle, as shown in Figure 1. The
2-
macrocycles are linked by ClO4 through weak Ag-O interac-
tions (Ag-O distances range from 2.944 to 4.000 Å) to form
The ligand psb was prepared frorn the reaction of 1,2-
bis(bromomethyl)benzene and sodium pyridine-4-thiolate. A
solution of 1,2-bis(bromomethyl)benzene (1.32 g, 5 mmol) and
sodium pyridine-4-thiolate (1.33 g, 10 mmol ) in MeCN (50
cm3) was heated to 60 °C for 3 h with vigorously stirring.
After cooling, the pale yellow solution was filtered. Removal
of the solvent gave an oil, which afforded a light yellow pow-
der (psb) on recrystallization from CH2Cl2/Et2O/hexane (yield
1.41 g, 84%).
The psb ligand possesses four possible bonding sites, i.e.,
two sulfur and two nitrogen atoms. Owing to the poor metal-
Copyright © 2000 The Chemical Society of Japan

Chemistry Letters 2000
29
Yamaguchi, and K. Ogura, Nature, 378, 468(1995). b) M.
Fujita, S. -Y. Yu, T. Kusukawa, H. Funaki, K. Ogura, and
K. Yamaguchi, Angew. Chem., Int. Ed. Engl., 37, 2082
(1998). c) P. S. Stang and B. Olenyuk, Acc. Chem. Res.,
30, 502(1997). d) R. -D. Schnebeck, E. Freisinger, and B.
Lippert, Angew. Chem., Int. Ed. Engl., 38, 168 (1999).
a) J.-M. Lehn, "Supramolecular Chemistry --- Concepts
and Perspectives," VHC, Weinheim (1995). b) M.
Munakata, L. P. Wu, and T. Kuroda-sowa, Adv. Inorg.
Chem., 46, 173(1999).
a) G. S. Hanan, C. R. Arana, J. -M. Lehn, G. Baum, and D.
Fenske, Chem. Eur. J., 2, 1292(1996). b) G.S. Hanan, C.
R. Arana, J.-M. Lehn, and D. Fenske, Angew. Chem., Int.
Ed. Engl., 34, 1122 (1995).
a) D. M. Bassani, J. -M. Lehn, K. Fraomm, and D. Fenske,
Angew Chem., Int. Ed. Engl., 37, 2364(1998). b) A, M.
Garcia, F. J. Romero-Salguero, D. M. Bassani, J. -M.
Lehn, G. Baum, and D. Fenske, Chem. Eur. J., 5, 1803
(1999).
4
5
6
layer structure, Figure 2 represents the packing diagram along c
axis. As expected, each psb acts as bidentate ligand, in which
two nitrogen atoms from different pyridine groups coordinate
to two Ag atoms, respectively. The other psb coordinates to
same two silver atoms in the opposite direction to meet linear
coordination of the silver atoms. Therefore, two psb ligands
are linked by two silver atoms forming a thirty-membered
macrocycle with the length of 2.0 nm, the Ag-Ag distance in
the macrocycle is 3.411 Å. Each silver atom is two-coordinat-
ed in a slightly distorted linear fashion of AgN2 The Ag-N
bond distances fall in the range of 2.142(2) to 2.148(2) Å,
which are much shorter than those found in the silver(I)-pyri-
dine complexes.8,9,11,13 The average bond angle of N-Ag-N, is
171.34(9)°.
7
8
M. Scherer, D. L. Caulder, D. W. Johnson, and K. N.
Raymond, Angew. Chem., Int. Ed. Engl., 38, 1588 (1999).
a) M. C. Hong, W. P. Su, R. Cao, W. J. Zhang, and J. X.
Lu, Inorg. Chem., 38, 600 (1999), b) W. P. Su, R. Cao, M.
C. Hong, J. T. Chen, and J. X. Lu, Chem. Commun.,
1998,1389.
9
M. C. Hong, W. P. Su, R. Cao, M. Fujita, and J. X. Lu,
Chem. Eur. J., (1999), in press.
10 a) M. J. Hannon, C. L. Painting, and W. Errington, Chem.
Commun., 1997, 1805. b) M. J. Hannon, C. L. Painting
and W. Errington, Chem. Commun., 1997, 307. c) G. K. H.
Shimizu, G. D. Enright, C. I. Ratcliffe, J. A. Ripmeester,
and D. D. M. Wayner, Angew. Chem., Int. Ed. Engl., 37,
1407 (1998). d) J. R. Black, N. R. Champness, W.
Levason, and G. Reid, Inorg. Chem., 36, 4432 (1997).
11 a) L. Carlucci, G. Ciani, D. M. Proserpio, and A. Sironi,
Inorg. Chem., 37, 5941 (1998). b) S. W. Keller, Angew.
Chem. Int. Ed. Engl., 36, 247(1997). c) M. J. Begley, P.
Hubberstey, C. E. Russell, and P. H. Walton, J. Chem.
Soc., Dalton Trans., 1994, 2483.
12 The intensity data were collected on a SIMENS SMART
CCD diffractometer with graphite-monochromated Mo-
Kα radiation at room-temperature. The crystal structure
was soloved by directed methods. All of the calculations
were performed by using the SHELXTL-PL version 5.5
package on an HP 5/75 computer. Crystallographic details
and complete listings have been deposited at the
Cambridge Crystallographic.
Further studies, such as, anion-exchange properties of
complexes with other weakly coordinating anions, which may
result in the insertion of the anion into the macrocycle or struc-
tural change, and self-assembly of the ligand bsp and its deri-
vation with other metal ions will be reported in full paper.
This work was supported by the NNSF of China and by
NSF of Fujian Province. M.C.H. thanks the Croucher
Foundation of Hong Kong for financial support.
References and Notes
1
M. Fujita, Chem. Soc. Rev., 27, 417(1998); O. M. Yaghi,
H. Li, C. Davis, D. Richardson, and T. L. Groy, Acc.
Chem. Res., 31, 474 (1998).
2
a) O. M. Yaghi, G. Li, and H. Li, Nature, 378, 703(1995).
b) G. B. Gardner, D. Venkataraman, J. S. Moore, and S.
Lee, Nature, 374, 792(1995). c) T. H. Hennigar, D. C.
MacQuarrie, P. Losier, R. D. Rogers, and M. J.
Zaworotko, Angew. Chem., Int. Ed. Engl., 36, 972 (1997).
d) B. F. Abrahams, P. A. Jackson, and R. Robson. Angew.
Chem., Int. Ed. Engl., 37, 2656(1998). e) D. D. L.
Goodgame, D. A. Grachvogel, and D. J. Williams, Angew.
Chem., Int. Ed. Engl., 38, 153(1999).
13 a) J. S. Fleming, K. L. V. Mann, C. -A. Carraz, E.
Psillakis, J. C. Jeffery, J. A. McCleverty, and M. D. Ward,
Angew. Chem., Int. Ed. Engl., 37, 1279 (1998). b) M. A.
Withersby, A. J. Blake, N. R. Champness, P. Hubberstey,
W. -S. Li, and M. Schröder, Angew. Chem., Int. Ed. Engl.,
36, 2327 (1997). c) R. Vilar, D. M. P. Mingos, A. J. P.
White, and D. J. Williams, Angew. Chem., Int. Ed. Engl.,
37, 1258(1998).
3
a) M. Fujita, D. Ogura, M. Miyazawa, H. Oka, K.