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W.-S. Hong et al. / Journal of Organometallic Chemistry 689 (2004) 277–285
3. Experimental
3.1. General
109 °C. IR (KBr film) m(CO): 2041, 2014, 1993 cmꢁ1. The
dark red band produced complex 3 (276 mg, 24.1%). m.p.
131–132 °C. Anal. Calc. for Fe2C14H7N3S3: C, 27.79; H,
1.65; N, 6.83; S, 15.52. Found: C, 27.70; H, 1.48; N,
6.89; S, 15.62%. The brown band produced complex 4
(154 mg, 18.2%). m.p. 108–109 °C. Anal. Calc. for
Fe4C23H12N6O11S4: C, 30.67; H, 1.33; N, 9.33; S, 14.22.
Found: C, 30.58; H, 1.39; N, 9.30; S, 14.24%. The orange
band produced complex 5 (136 mg, 30.1%). m.p. 79–80
°C. Anal. Calc. for FeC14H12N6O 2S4: C, 34.97; H, 2.50;
N, 17.49; S, 26.65. Found: C, 35.01; H, 2.44; N, 17.42; S,
25.53%. Substantial amount of iron cluster, Fe3(CO)12,
was also collected.
Diiron nonacarbonyl was prepared by photolysis of
iron pentacarbonyl (Aldrich) in glacial acetic acid [10].
Solvents were dried (sodium/benzophenone, P4O10) and
distilled under nitrogen prior to use. Thiophene-2-car-
boxaldehyde (Aldrich) was distilled by a Kugelrohr dis-
tillation apparatus under reduced pressure (0.1 mm Hg)
prior to use. All other chemicals were reagent grade and
used without further purification. The NMR spectra
were recorded on a Bruker DX-300 NMR spectrometer
(1H, 299.95 MHz; 13C, 75.43 MHz). Chemical shifts were
referenced to TMS, and deuterated acetone (Janssen)
was used as a solvent and as a secondary reference. Mass
spectra were obtained from a Micromass Platform II
spectrometer. IR spectra were recorded from a Mattson
Genesis FTIR spectrophotometer. Elemental analyses
were performed using a Perkin–Elmer 2400, 2400II ele-
mental analyzer. Crystals for X-ray diffraction were ob-
tained from acetone (ligand 1) or from ether/hexane (1:4)
mixed solution (complexes 2, 3, 4, and 5). A single crystal
was mounted on a glass fiber and the X-ray diffraction
intensity data were measured on a Rigaku AFC7S dif-
fractometer with graphite monochromated Mo Ka ra-
diation at room temperature.
1H NMR, 13C NMR, IR, and MS spectral data for 1,
3, 4, and 5 are tabulated in Table 6.
4. Supplementary material
Crystallographic data for the structural analysis have
been deposited with the Cambridge Crystallographic
Data Center, CCDC No. 216502 (1), 216503–216505
ð3–5Þ. Copies of this information may be obtained free
of charge from The Director, CCDC, 12 Union Road,
Cambridge CB2 1EZ, UK (Fax: +44-1223-336033;
e-mail: deposit@ccdc.cam.ac.uk or http://www.ccdc.
3.2. Synthesis of thiophene-2-carboxaldehyde thiosemi-
carbazone (1)
Acknowledgements
The synthesis of Schiff base 1 employed the usual
approach of condensation in alcohol solution [11].
Thiophene-2-carboxaldehyde (1.40 g, 12.5 mmol) and
thiosemicarbazide (0.91 g, 10 mmol) were refluxed in
ethanol (Merck, 20 ml) for 1 h. The solvent was removed
by filtration. The yellow precipitate was washed with
several portions of ether to give pure product 1 (1.40 g,
75%). m.p. 176:6–177:0 °C. Anal.
The authors express their appreciation to the
National Science Council (Taiwan, ROC) and National
Dong Hwa University for providing the financial sup-
port necessary to carry out this study.
References
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