SHORT COMMUNICATION
DOI: 10.1002/ejic.200701126
Synthesis of Copper Halide Coordination Polymers with Ligands Formed by In
Situ Cyclization of 2-Aminopyrimidine and Ethanol
Minghui Bi,
[a]
Guanghua Li,
[a]
Jia Hua,
[a]
Yingjie Lin,
[a]
Junjun Cao,
[a]
Zhan Shi,*
[a]
and
Shouhua Feng
[a]
Keywords: Coordination polymers / Copper / Halides / In situ cyclization
The design and synthesis of coordination polymers from tran-
sition metals and organic ligands have been extensively
studied for their crystallographic diversity and potential ap-
plications. Recently, the synthesis of coordination polymers
by hydro(solvo)thermal in situ metal/ligand reactions has
drawn great interest because of its potential to generate
novel coordination architectures and new organic reactions.
As described in our manuscript, the nitrogen heterocyclic
Introduction
Hydro(solvo)thermal in situ metal/ligand reactions, as a
new bridge between coordination chemistry and organic
synthetic chemistry,
[1]
are of great interest for the discovery
of novel coordination architectures especially those that
are inaccessible by direct preparation and organic reac-
tions.
[2]
Although in situ metal/ligand reactions have been
extensively investigated for many decades, only a few kinds
of organic ligand in situ reactions have been found under
hydro(solvo)thermal conditions, such as the transformation
of inorganic and organic sulfur,
[3c]
dehydrogenative carbon–
carbon coupling,
[3b]
hydroxylation of aromatic rings,
[3a]
and
cycloaddition of organic nitriles with azide and ammo-
nia.
[3d]
The exploration of new in situ metal/ligand reactions
has remained a challenge for researchers in both coordina-
tion and organic chemistry.
A few kinds of ligand in situ reaction have been found
in copper halides system,
[4]
but the use of the reduction of
Cu
2+
to Cu
+
is rare relative to the efforts directed towards
CuX (X = halide).
[5]
Because the oxidation ability of XO
4
1–
is much stronger than that of Cu
2+
, we used not only the
reduction of Cu
2+
to Cu
+
, but also the reduction of XO
4
1–
to X
–
in order to discover novel structures. In this com-
munication, we report two examples of the simultaneous
redox of Cu
2+
to Cu
+
and XO
4
1–
to X
–
(X = Cl, I) and
[a] State Key Laboratory of Inorganic Synthesis & Preparative
Chemistry, College of Chemistry, Jilin University,
Changchun 130012, P. R. China
Fax: +86-431-85168624
E-mail: zshi@mail.jlu.edu.cn
Supporting information for this article is available on the
WWW under http://www.eurjic.org or from the author.
Eur. J. Inorg. Chem. 2008, 1035–1038 © 2008 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim 1035
2,3-dihydroimidazo[1,2-a]pyrimidine (C
6
H
7
N
3
) ligand was
synthesized by an in situ reaction starting from 2-amino-
pyrimidine and ethanol. At the same time, two luminescent
copper halide coordination polymers, (CuCl)
3
C
6
H
7
N
3
and
(CuI)
2
C
6
H
7
N
3
, were assembled under solvothermal condi-
tions.
(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
Germany, 2008)
their self-assembly under solvothermal conditions to afford
luminescent a copper(I) layer and a chain polymer, (CuCl)
3
-
C
6
H
7
N
3
(1) and (CuI)
2
C
6
H
7
N
3
(2) (C
6
H
7
N
3
= 2,3-dihy-
droimidazo[1,2-a]pyrimidine), respectively. We found an in
situ cycloaddition of 2-aminopyrimidine and EtOH.
Results and Discussion
Single-crystal X-ray structure analysis of the two com-
pounds showed that compound 1 is a two-dimensional in-
organic–organic CuCl coordination polymer and that com-
pound 2 is a one-dimensional hybrid CuI chain. The struc-
ture of compound 1 can be decomposed into two parts of
crystallographically independent metal atom centers (Fig-
ure 1). The Cu center, a Cl atom, and the ligand make up
a metal–ligand chain, and the Cu center adopts a distorted
tetrahedral geometry coordinated to two Cl atoms and two
N atoms from the ligand. The other part of the structure is
a (CuCl)
6
chain, which is constructed by combination of
two chair-shaped trinuclear Cu
3
Cl
3
units that are joined
through six Cl anions. The unit structure feature of the
chain is similar to the double six-membered (D6R, hexago-
nal prism) rings found in zeolites, and this structure is an
important and attractive unit in zeolites.
[6]
As shown in Fig-
ure 1, each metal–ligand chain connects two double six-
membered rings through the Cl atoms to form the 2D grid
of compound 1. The structure of compound 2 is a zigzag
ladder chain; each copper cation serves as a tetrahedral co-
ordination site where each iodine anion is coordinated to
three copper cations (Figure 2). This structure can be
attributed to the ligand, and it is different from other ladder