300
J.-L. Xie et al. / Polyhedron 22 (2003) 299ꢄ305
/
2. Experimental
2.2.2. Synthesis of [BrBzPy][Ni(bdt)2] (2)
[BrBzPy][Ni(bdt)2] (2) was prepared by the same
procedure. Yield: 72%. Anal. Found: C, 49.2; H, 3.3;
N, 2.4. Calc. for C24H19BrNNiS4: C, 49.0; H, 3.3; N,
2.4%. IR (cmꢀ1): 3035 (w), 2968 (s, n(CH)), 2851 (m,
2.1. Reagents and physical measurements
All chemicals and solvents were of reagent grade and
were used without further purification. Benzene-1,2-
dithiol was purchased from TCI chemicals, 1-(4?-fluo-
robenzyl)pyridinium chloride ([FBzPy]Cl) and 1-(4?-
bromobenzyl)pyridinium bromide ([BrBzPy]Br) were
prepared as described in the literature [8]. Elemental
n(CH)), 1480 (vs, d(CH)), 1411 (s), 737, 664 (vs, n(CÃ
/
S)). 1H NMR: d 9.14 (2H, CHC(F)CH), 8.62 (1H, ArH,
pyridine ring), 8.16 (2H, CH(C)CH, phenyl ring), 7.67,
7.49 (4H, C6H4S2), 5.82 (4H, (CH)2N(CH)2, pyridine
ring), 2.63 (2H, CH2N).
analyses were performed with a PerkinꢄElmer 240
/
analytical instrument. A Bruker IFS66V FT IR spectro-
photometer was used, and the measurements were made
by the KBr disk method. 1H NMR spectra were
recorded on a Bruker AVANCE300 spectrometer in
DMSO-d6 solution at 20 8C. The ESR spectra were
recorded on a Bruker ER200D-SRC spectrometer at 100
kHz modulation at room temperature. Mn2ꢃ in MgO
was used as the standard sample. Magnetic susceptibility
data on powder-sample were measured over a tempera-
2.2.3. Crystal structure determination
Diffraction data of complexes 1 and 2 were collected
at 293 K on a Siemens SMART CCD area detector
equipped with graphite-monochromated Mo Ka radia-
tion. Crystal data collection parameters and refinement
details are listed in Table 1. All computations were
carried out using the SHELXTL-PC program package [9].
The structure was solved by direct method and refined
on F2 by full-matrix least-squares methods. All the
nonhydrogen atoms were refined anisotropically. Hy-
drogen atoms were placed in their calculated positions
and refined following the riding model.
ture range of 2ꢄ
300 K on a Model Maglab System2000
/
magnetometer. Diamagnetic corrections were made
using Pascal’s constants. Cyclic voltammograms were
recorded on a EG&G potentiostat/galvanostat model
273 analyzer in a one-comportment cell (glassy carbon
working electrode, Pt counter electrode and Agꢄ
/
AgCl
3. Results and discussions
reference electrode) under an Ar atmosphere at 25 8C in
MeCN solution with approximately 0.1 M [Bu4N]ClO4
3.1. Crystal structure
as conducting electrolyte. In the ꢀ
/
1.2 to ꢃ1.2 V region,
/
a potential scan rate of 100 mV sꢀ1 was used.
An ORTEP drawing with the atomic labeling of the
molecular unit is shown in Fig. 1. Selected bond
distances and bond angles are listed in Table 2. The
molecular structure of 1 contains two different, inde-
pendent halves of centrosymmetric [Ni(bdt)2]ꢀ anions,
and one [FBzPy]ꢃ cation.
The nickel atoms are each surrounded by four sulfur
atoms in square-planar geometry, which is markedly
different from a spiro compound Si(bdt)2 [10]. As for the
2.2. Preparations
2.2.1. Synthesis of [FBzPy][Ni(bdt)2] (1)
Under nitrogen atmosphere at room temperature,
benzene-1,2-dithiol (284 mg, 2 mmol) was added to a
solution of sodium metal (92 mg, 4 mmol) in 25 ml of
absolute ethanol. A solution of NiCl2×
mmol) in ethanol was added, resulting in the formation
of a muddy redꢄbrown color. Following this, [FBzPy]Cl
/6H2O (240 mg, 1
Ni(1)-containing unit, the Ni(1)Ã
/
S(1) and Ni(1)Ã
/
S(2)
˚
/
distances are 2.148 and 2.151 A, respectively. The values
(244 mg, 2 mmol) was added and the mixture allowed to
stand with stirring for 1 h, and then stirred for 24 h with
the presence of atmosphere. The color of the mixture
gradually turned green, indicating oxidation from a
dianionic species to the more stable monoanionic form.
The precipitate was washed with absolute ethanol and
ether and then dried. The crude product was recrystal-
lized twice from methylene chloride to give 368 mg dark
green needles. Yield: 69%. Anal. Found: C, 54.8; H, 3.6;
N, 2.6. Calc. for C24H19FNNiS4: C, 54.7; H, 3.6; N,
2.7%. IR (cmꢀ1): 3033 (w), 2964 (s, n(CH)), 2854 (m,
n(CH)), 1482 (vs, d(CH)), 1419 (s), 1224 (m), 737, 666
are in agreement with the analogous [Ni(bdt)2]ꢀ com-
plex reported [6b]. The SÃ
/
NiÃ/S bond angle within the
five-member ring is 91.77(2)8, which is slightly larger
than that observed in complex with substituent groups
on benzene rings [6c]. There exists a dihedral angle of
2.68 between C(1)C(2)C(3)C(4)C(5)C(6)S(1)S(2) (abbr.
C6S2) and the Ni(1)S(1)S(2) planes, so the anion adopts
an envelope conformation, and the Ni(1) atom deviates
˚
0.08 A from C6S2 plane. In Ni(2)-containing unit, the
˚
S bonds cover the range from 2.14 to 2.16 A and the
NiÃ
/
SÃNiÃ
/
/
S bond angle within the five-member ring is
91.29(3)8 which is in agreement with that of Ni(1)-
(vs, n(CÃ
/
S)). 1H NMR: d 9.15 (2H, CHC(F)CH),
˚
containing unit. The Ni(2) atom deviates 0.12 A from
8.60(1H, ArH, pyridine ring), 8.16 (2H, CH(C)CH,
phenyl ring), 7.61, 7.29 (4H, C6H4S2), 5.93 (4H,
(CH)2N(CH)2, pyridine ring), 2.63 (2H, CH2N).
C(7)C(8)C(9)C(10)C(11)C(12)S(3)S(4) plane and the
angle between C6S2 and the Ni(2)S(3)S(4) planes is
4.48. The Ni(1)C6S2 and Ni(2)C6S2 planes are nearly