Compounds with Terephthalate and 2-(4-Pyridyl)benzimidazole Ligands
Scheme 1. Three types of coordination modes for the PyBim ligands.
(0.102 g, 0.61 mmol), and H2O (15 mL) was stirred under ambient package.[8] The hydrogen atoms were generated geometrically except
conditions. Afterwards, the mixture was sealed in a Teflon-lined steel for water molecules. Crystallographic data are summarized in Table 1.
vessel and heated at 160 °C for 5 days. After slow cooling to room Selected bond lengths and angles are listed in Table 2.
temperature, the resulting product was recovered by filtration, washed
Crystallographic data for the structural analysis have been deposited
with the Cambridge Crystallographic Data Centre, reference numbers
CCDC-773909, -773910, -773911, and -773912 for compounds 1–4.
Copies of this data may be obtained from The Director, CCDC, 12
Union Road, CB2 1EZ, UK (Fax: +44-1233-336033; E-Mail: de-
posit@ccdc.cam.ac.uk or www: http:// www.ccdc.cam.ac.uk.)
with distilled water and dried in air (Yield 80 % ). C16H12N3O2: calcd.
C 69.06; N 15.10; H 4.35 %; found: C 69.13; N 14.87; H 4.74 %. IR
(KBr): ν = 3455 s, 1854 m, 1695 s, 1613 s, 1534 m, 1505 m, 1447 w,
˜
1433 s, 1372 m, 1314 s, 1277 s, 1210 m, 1131 m, 1060 s, 1014 s, 970
s, 879 m, 842 s, 772 s, 750 s, 723 s, 696 m, 616 w, 563 m, 481 s cm–1.
Co(PyBIm)2(HBDC)(BDC)0.5 (2):
A solution of CoCl2·4H2O
(0.152 g, 0.64 mmol), PyBIm (0.24 g, 1.22 mmol), 1,4-H2BDC acid
(0.160 g, 0.96 mmol), NaOH (0.022 g, 0.55 mmol) and H2O (15 mL)
was stirred under ambient conditions. Afterwards, the mixture was
sealed in a Teflon-lined steel vessel and heated at 130 °C for 5 days.
After slow cooling to room temperature, the resulting product was
recovered by filtration, washed with distilled water and dried in air
Supporting Information (see footnote on the first page of this article):
TGA and DSC traces of compounds 1–4. Inverse susceptibility with
linear regression based upon Curie–Weiss law for complexes 2 and 3.
(Yield 85 %). C36H25CoN6O6: calcd. C, 62.08; N, 12.06; H, 3.62 %; Results and Discussion
found: C, 61.79; N, 12.32; H, 3.91 %. IR (KBr): ν = 3422 s, 3196 s,
˜
Syntheses
1932 m, 1674 s, 1613 s, 1563 s, 1550 m, 1507 s, 1430 s, 1408 s, 1316
m, 1273 m, 1234 m, 1214 m, 1014 s, 958 m, 884 m, 842 s, 814 m,
789 s, 739 s, 698 s, 682 s, 532 m cm–1.
Complexes 2–4 were synthesized with transition metal chlo-
rides in hydrothermal reaction condition, respectively. How-
ever, a series of parallel experiments show that when the metal
chlorides were replaced with the corresponding metal acetates,
the complexes could not be obtained, which may be due to the
influence of CH3COO–. It is worthwhile to note that, more
interestingly, the organic compound 1 was isolated from the
similar reaction condition with Mn(CH3COO)2·4H2O as initial
reagent. However, if the synthesis was carried out under the
same reaction conditions but in absence of Mn2+ or Co2+ ions,
no compound 1 could be obtained, which suggests that the
presence of metal ions is important to obtain the structure al-
though the role of the metal ions in the system remains unclear.
Ni(PyBIm)2(HBDC)(BDC)0.5 (3): Complex 3 was synthesized in an
analogous procedure to 2, except NiCl2·4H2O (0.144 g, 0.64 mmol)
was used instead of CoCl2·4H2O (Yield 80 %). C36H25NiN6O6: calcd.
C, 62.10; N, 12.07; H, 3.62 %; found: C, 61.79; N, 12.09; H, 4.04 %.
IR (KBr): ν = 3424 s, 3195 s, 1932 m, 1672 s, 1614 s, 1567 s, 1542
˜
m, 1508 s, 1430 s, 1406 s, 1315 m, 1258 m, 1258 m, 1214 m, 1017
s, 957 m, 884 m, 845 s, 814 m, 788 s, 740 s, 701 m, 682 s, 532 m
cm–1.
Zn(PyBIm)(BDC)·H2O (4): A solution of ZnCl2·4H2O (0.137 g,
1.00 mmol), PyBIm (0.195 g, 1.00 mmol), 1,4-H2BDC acid (0.166 g,
1.00 mmol), NaOH (0.034 g, 0.85 mmol) and H2O (15 mL) was
stirred under ambient condition. Afterwards, the mixture was sealed in
a Teflon-lined steel vessel and heated at 130 °C for 5 days. After slow
cooling to room temperature, the resulting product was recovered by
filtration and washed with distilled water and dried in air (Yield 90 %).
C20H15N3O5Zn: calcd. C, 54.26; N, 9.49; H, 3.41 %; found: C, 54.62;
Thermal Properties
Compound 1 does not show apparent weight losses up to
250 °C. A sharp weight loss occurs between 250–360 °C,
which displays the decomposing of the overall molecule. Be-
cause no coordination or crystal water molecules are present
in the complexes 2 and 3, the two complexes are rather stable
and have no weight losses up to 370 °C. Complex 4 loses its
coordination water in the range of 45–150 °C, the observed
weight loss is 3.98 %, which is in accordance with the calcu-
lated weight loss (4.07 %).
N, 9.55; H, 3.88 %. IR (KBr): ν = 3451 s, 3052 s, 1869 m, 1614 s,
˜
1563 w, 1536 m, 1500 m, 1478 m, 1448 w, 1371 m, 1277 s, 1143 m,
1130 m, 1060 s, 1015 s, 970 s, 879 m, 842 s, 771 m, 745 s, 705 m,
695 m, 593 m, 563 m cm–1.
X-ray Crystallography
Suitable single crystals of 1–4 were carefully selected under an optical
microscope and glued to thin glass fibers. The diffraction data were
collected with a Siemens Smart CCD diffractometer with graphite-
monochromated Mo-Kα radiation (λ = 0.71073 Å) at 293 K. An empir-
ical absorption correction was applied using the SADABS program.[7]
The structures were solved by direct methods and refined by full-ma-
Crystal Structures
Compound 1 crystallizes in orthorhombic space group Pbca.
trix least-squares methods on F2 by using the SHELXTL-97 program As shown in Figure 1, in the molecule structure the PyBIm co-
Z. Anorg. Allg. Chem. 2011, 282–288
© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
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