Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistry, 42:135–139, 2012
Copyright ꢀ Taylor & Francis Group, LLC
C
ISSN: 1553-3174 print / 1553-3182 online
DOI: 10.1080/15533174.2011.609503
Syntheses and Crystal Structures of Two Azide-Bridged
Dinuclear Zinc(II) Complexes with Schiff Bases and Halides
Rui-Hua Hui,1 Peng Zhou,1 and Zhong-Lu You2
1Department of Chemistry, Anshan Normal University, Anshan, P. R. China
2Department of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian, P. R. China
EXPERIMENTAL
Two end-on azide-bridged dinuclear Schiff base zinc(II) com-
Materials and Instrumentation
plexes, [Zn2Br2(µ1,1-N3)L1 ]·H2O (1) and [Zn2I2(µ1,1-N3)L2 ]·I (2)
2
2
(L1 = 4-bromo-2-[(2-isopropylaminoethylimino)methyl]phenol, L2
= 2-ethoxy-6-[(2-ethylaminoethylimino)methyl]phenol), have been
synthesized and characterized by elemental analysis, IR spec-
tra, and single-crystal X-ray diffraction. One Zn atom in (1)
is five-coordinated in a square pyramidal geometry, while the
other Zn atom in (1) and the Zn atoms in (2) are in tetrahedral
geometries.
Infrared spectra were recorded in a Bruker IFS-125 model
FT-IR spectrophotometer as KBr pellets. C, H, and N anal-
yses were carried out using a Perkin-Elmer model 240 an-
alyzer. 5-Bromosalicylaldehyde, 3-ethoxysalicylaldehyde, N-
isopropylethane-1,2-diamine, and N-ethylethane-1,2-diamine
were purchased from Lancaster Company and other chemicals
were of analytical-grade quality and used without further purifi-
cation.
Keywords azide, crystal structure, Schiff base, synthesis, zinc
complex
Synthesis of L1
To a methanol solution (10 ml) of 5-bromosalicylaldehyde
(1.0 mmol, 201.0 mg) was added a methanol solution (10 ml)
of N-isopropylethane-1,2-diamine (1.0 mmol, 102.2 mg), with
continuous stirring at room temperature. The mixture was stirred
for about 10 minutes and the solvent was evaporated to give
yellow solid, which was washed three times with cold methanol,
and dried in a vacuum over anhydrous CaCl2. Yield: 95%. Anal.
Calcd. for C12H17BrN2O: C, 50.5; H, 6.0; N, 9.8. Found: C,
50.8; H, 6.1; N, 9.6%. Characteristic IR data (KBr, cm−1): 1645
vs.
INTRODUCTION
Schiff bases have been widely used as chelating ligands in
the field of coordination chemistry for their versatile structures
and potential applications.[1–3] The azide anions can link two or
more metal atoms in the µ1,1 (end-on, EO), µ1,3 (end-to-end,
EE), and many other modes, yielding various polynuclear and
one-, two-, or three-dimensional species of different topologies,
depending on the metal atom and the coligands used.[4–6] In or-
der to investigate the synthesis and self-assembly of the Schiff
base zinc complexes with azide bridges and halide anions, in
Synthesis of L2
To a methanol solution (10 ml) of 3-ethoxysalicylaldehyde
(1.0 mmol, 166.2 mg) was added a methanol solution (10 ml)
of N-ethylethane-1,2-diamine (1.0 mmol, 88.2 mg), with con-
tinuous stirring at room temperature. The mixture was stirred
for about 10 min and the solvent was evaporated to give yellow
solid, which was washed three times with cold methanol and
dried in a vacuum over anhydrous CaCl2. Yield: 92%. Anal.
Calcd. for C13H20N2O2: C, 66.1; H, 8.5; N, 11.8. Found: C,
66.5; H, 8.5; N, 11.7%. Characteristic IR data (KBr, cm−1):
1643 vs.
this article, two new dinuclear zinc complexes, [Zn2Br2(µ1,1
-
N3)L1 ]·H2O (1) and [Zn2I2(µ1,1-N3)L2 ]·I (2), where L1 =
2
2
4-bromo-2-[(2-isopropylaminoethylimino)methyl]phenol, and
L2 = 2-ethoxy-6-[(2-ethylaminoethylimino)methyl]phenol (see
Scheme 1), were synthesized and structurally characterized. To
our knowledge, a copper(II) complex[7] and a zinc(II) complex[8]
of L1 were reported, while no complexes with L2 have been re-
ported so far.
Synthesis of [Zn2Br2(1,1-N3)L1 ]·H2O (1)
2
An aqueous solution (1 ml) of ZnBr2 (0.1 mmol, 22.5 mg)
was added to a methanol solution (10 ml) of L1 (0.1 mmol, 28.5
mg) and NaN3 (0.1 mmol, 6.5 mg), with continuous stirring
at room temperature. The final clear mixture was allowed to
stand at room temperature for several days. Colorless crystals
Received 24 October 2009; accepted 28 July 2011.
Address correspondence to Rui-Hua Hui, Department of Chem-
istry, Anshan Normal University, Anshan 114007, P. R. China. E-mail:
ruihua hui@126.com
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