Trans influence and steric effect on the distortions in planar NiS 4, NiS2PN, and NiS2P2 chromophores

Article abstract of DOI:10.1002/zaac.201200103

The planar diamagnetic complexes [Ni(achdtc)₂] (1),[Ni(achdtc)(PPh₃)(NCS)] (2), and [Ni(achdtc)(PPh ₃)₂]ClO₄·0.5EtOAc (3) (achdtc = allylcyclohexylcarbodithioate) were prepared, characterized by elemental analysis, electronic, IR, NMR (¹H, ¹³C, and ³¹P) spectroscopy and the crystal structures were determined by single-crystal X-ray crystallography. The characteristic thioureide bands occur at 1478, 1503, and 1507 cm^-1 for 1, 2, and 3, respectively and the corresponding ¹³C chemical shifts are observed at 207.67, 204.16, and 202.31 ppm. ³¹P chemical shifts are observed at δ = 29.24 and 22.73 ppm for 2 and 3, respectively, indicating a strong interaction. Electronic spectral bands are observed at 480, 483, and 475 nm for 1, 2, and 3, corresponding to d_z2 → d_xy/d_x2-y2 transitions. Ni-S distances are asymmetric. The trans influence of PPh ₃ elongates the Ni-S bonds. The decrease in the S-Ni-S bite angle in 2 [78.80(16)°] and in 3 [78.36(2)°] compared to that observed in 1 [79.42(3)°] is due to the steric crowding of PPh₃ around the central metal atom. A comparison of the bond parameters of compounds 1-3 shows a change in the arrangement from a planar NiS₄ chromophore to distorted planar NiS₂P₂ chromophores. The observed distortion from planar to tetrahedral arrangement is influenced by the bulky triphenylphosphine ligand. Copyright

Full text of DOI:10.1002/zaac.201200103

ARTICLE
DOI: 10.1002/zaac.201200103
trans Influence and Steric Effect on the Distortions in Planar NiS4, NiS2PN,
and NiS2P2 Chromophores
Subramaniam Srinivasan,[a] Kuppukkannu Ramalingam,*[a] and Corrado Rizzoli[b]
Keywords: Carbodithioates; Nickel; Thiocyanate-N; Thioureides; X-ray diffraction
Abstract. The planar diamagnetic complexes [Ni(achdtc)2] (1), Electronic spectral bands are observed at 480, 483, and 475 nm for 1,
[Ni(achdtc)(PPh3)(NCS)] (2), and [Ni(achdtc)(PPh3)2]ClO4·0.5EtOAc 2, and 3, corresponding to dz2 Ǟ dxy/dx2–y2 transitions. Ni–S distances
(3) (achdtc = allylcyclohexylcarbodithioate) were prepared, charac-
are asymmetric. The trans influence of PPh3 elongates the Ni–S bonds.
The decrease in the S–Ni–S bite angle in 2 [78.80(16)°] and in 3
terized by elemental analysis, electronic, IR, NMR (1H, 13C, and 31P)
spectroscopy and the crystal structures were determined by single- [78.36(2)°] compared to that observed in 1 [79.42(3)°] is due to the
crystal X-ray crystallography. The characteristic thioureide bands oc-
cur at 1478, 1503, and 1507 cm–1 for 1, 2, and 3, respectively and the
corresponding 13C chemical shifts are observed at 207.67, 204.16, and
202.31 ppm. 31P chemical shifts are observed at δ = 29.24 and
steric crowding of PPh3 around the central metal atom. A comparison
of the bond parameters of compounds 1–3 shows a change in the ar-
rangement from a planar NiS4 chromophore to distorted planar NiS2P2
chromophores. The observed distortion from planar to tetrahedral ar-
22.73 ppm for 2 and 3, respectively, indicating a strong interaction. rangement is influenced by the bulky triphenylphosphine ligand.
1. Introduction
2. Experimental Section
All reagents and solvents employed were commercially available ana-
lytical grade materials and were used as supplied without further puri-
fication. IR spectra were recorded with an Avatar Nicolet FT-IR spec-
trophotometer [range 4000–400 cm–1] as KBr pellets of the com-
pounds. Electronic spectra were recorded in CH2Cl2 with a Hitachi U-
Dithiocarbamate complexes of Group X metal ions involv-
ing phosphines and nitrogenous ligands show structural nov-
elty and interesting biological properties.[1,2] The reactivity of
dithiocarbamate complexes is influenced marginally by the
substituents on dithiocarbamate ligands.[3,4] Divalent nickel
complexes of dithiocarbamates are diamagnetic and are of dis-
torted planar arrangement.[5,6] Divalent nickel bisdithiocarb-
amates are borderline acceptors and they prefer to react with
soft Lewis bases such as phosphines and hard bases such as
nitrogenous ligands. Structural studies on [Ni(dtc)(PPh3)X]
1
2001 double beam spectrometer. H, 13C, and 31P NMR spectra were
recorded with a Bruker AMX-400 spectrometer at room temperature
using CDCl3 as solvent.
2.1 X-ray Crystallography
–
complexes [dtc = S2CN(C2H5)2 , S2CN(CH3)(C2H4OH)–,
Intensity data were collected at ambient temperature (295 K) with a
Bruker APEXII CCD diffractometer with graphite monochromated
Mo-Kα radiation (λ = 0.71073 Å) and were corrected for absorption
with a multi-scan technique.[12–14] The structures were solved by direct
methods using SIR97 and were refined by SHELX97.[15] The non-
hydrogen atoms were refined anisotropically and all the hydrogen
atoms were fixed geometrically. Molecular plots were obtained using
the ORTEP-3 program.[16]
–
–
–
S2CN(C2H4OH)2 , S2CN(C3H7)2 , and S2CN(C5H10)2 ; X =
Cl–, NCS–, CN–] have been reported from our laboratory.[7–10]
In continuation of our interest[11] in exploring the synthetic and
structural chemistry of transition metal dithiocarbamates, in
this paper we report the synthesis, spectral, and structural char-
acterization of [Ni(achdtc)2] (1), [Ni(achdtc)(PPh3)(NCS)] (2),
[Ni(achdtc)(PPh3)2]ClO4·0.5EtOAc (3) [achdtc = allylcyclo-
hexylcarbodithioate].
2.2 Preparation of the Complexes
* Prof. Dr. K. Ramalingam
2.2.1 Bis(N-allylcyclohexylcarbodithioato)nickel(II),
[Ni(achdtc)2] (1)
Fax: +91-414-422265
E-Mail: krauchem@yahoo.com
[a] Department of Chemistry
A mixture of N-allylcyclohexylamine (0.29 mL, 2 mmol) and CS2
(76 mg, 1 mmol) in ethanol (50 mL) was kept under ice cold condition
(–5 °C) for 10 min and to the resultant pale yellow solution,
NiCl2·6H2O (238 mg, 1 mmol) in water (25 mL) was added slowly
with vigorous stirring. A dark green precipitate separated, which was
filtered, washed with water and subsequently with ether. The solid
was dried with anhydrous calcium chloride (yield 95%; dec.: 220 °C).
Annamalai University
Annamalainagar, 608 002, India
[b] Department of General and Inorganic Chemistry
University of Parma
Parma-43100, Italy
Supporting information for this article is available on the WWW
under http://dx.doi.org/10.1002/zaac.201200103 or from the au-
thor.
1356
© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Z. Anorg. Allg. Chem. 2012, 638, (9), 1356–1361

Planar NiS4, NiS2PN, and NiS2P2 Chromophores
Analytical data: C20H32N2NiS4 (487.43): C 49.01 (calcd. 49.29); H
6.33 (6.62); N 5.46 (5.75)%.
The same set of transitions have been supported by an earlier
report.[19] The band observed at 629 nm in the parent bisdi-
thiocarbamate shifted to higher wave length in the mixed li-
gand complex. The band at 480 nm in the mixed ligand com-
plex showed a red shift on replacement of chelating dithio-
carbamate with PPh3 and NCS–. Electronic spectra of the com-
plexes are in line with the square-planar arrangement around
nickel in the complexes 1–3, confirmed by their single-crystal
X-ray structures.
2.2.2 (N-allylcyclohexylcarbodithioato)(thiocyanato-N)(tri-
phenylphosphine)nickel(II), [Ni(achdtc) (PPh3) (NCS)] (2)
A mixture of [Ni(achdtc)2], (146 mg, 0.3 mmol), PPh3 (160 mg,
0.6 mmol), NiCl2·6H2O (70 mg, 0.3 mmol), and NH4SCN (50 mg,
0.6 mmol) was heated to reflux for 3 h in an acetonitrile-methanol
solvent mixture (1:1 v/v, 50 cm3) and additionally the solution was
concentrated to ca. 20 cm3. The resultant dark purple red solution was
left aside for evaporation. After two days purple red solid separated
from the solution, which was filtered and dried with anhydrous cal-
cium chloride. Single crystals suitable for X-ray analysis were obtained
by repeated re-crystallization from the same solvent mixture (yield
75%; dec., 189 °C). Analytical data: C29H31N2NiPS3 (593.40): C
58.45 (calcd. 58.70); H 5.01 (5.27); N 4.43 (4.72)%.
3.2. IR Spectroscopic Studies
For complexes 1–3 ν(C–N) thioureide bands are observed
at 1478, 1503, and 1507 cm–1 respectively. An increase in the
wave number of the mixed ligand complexes (1503 cm–1 for 2
and 1507cm–1 for 3) compared to that observed in its parent
complex 1 (1478 cm–1) is attributed to the enhanced meso-
meric drift of electron density towards the nickel atom through
S2C–NϽ bond from the dithiocarbamate. The ν(C–S) stretch-
ing bands are observed around 1100 cm–1 (1, 2, and 3) without
any splitting, supporting the bidentate coordination of the di-
thiocarbamate moiety.[20] The observed stretching band at
2.2.3 Bis(triphenylphosphine)(N-allylcyclohexylcarbo-
dithioato)nickel(II) Perchlorate, Semi Ethyl Acetate Solvate
[Ni(achdtc)(PPh3)2]ClO4·0.5EtOAc (3)
A mixture of Ni(achdtc)2 (244 mg, 0.5 mmol), PPh3 (524 mg, 2 mmol),
NiCl2 6H2O (119 mg, 0.5 mmol), and NH4ClO4 (115 mg, 1 mmol) was
heated to reflux for about 2 h in dichloromethane-ethyl acetate solvent
mixture (3:1, 50 cm3) and was concentrated to ca. 25 cm3. The purple
red solution obtained was filtered and was left for evaporation. The
separated solid was filtered and dried and single crystals suitable for
X-ray analysis were obtained by repeated re-crystallization from the
same solvent mixture (yield, 75%; dec., 225 °C). Analytical data:
C48H50ClNNiO5P2S2 (941.1): C 61.19 (calcd. 61.25); H 5.29 (5.35) N
1.43 (1.49)%.
“
2083 cm–1 for complex 2 is attributed to the N” coordinated
thiocyanate anion.
3.3 Cyclovoltammetric Studies
CV studies indicate that the complexes 2 and 3 undergo one
electron reduction processes[7] [NiII Ǟ NiI] with reduction po-
tentials, –1199 mV and –1200 mV, respectively. Lower re-
duction potentials observed for complexes 2 and 3 compared
to 1 (–1352 mV) indicate the ease of electron addition in the
mixed ligand complexes due to the presence of PPh3, NCS–
around the nickel atom.
Crystallographic data and structure refinement parameters of com-
pounds 1–3 are summarized in Table 1.
Crystallographic data (excluding structure factors) for the structures in
this paper have been deposited with the Cambridge Crystallographic
Data Centre, CCDC, 12 Union Road, Cambridge CB21EZ, UK. Copies
of the data can be obtained free of charge on quoting the depository
numbers CCDC-823923 (1), CCDC-833645 (2), and CCDC-857725
(3) (Fax: +44-1223-336-033; E-Mail: deposit@ccdc.cam.ac.uk,
http://www.ccdc.cam.ac.uk).
3.4 NMR Spectroscopic Studies
NMR spectra were recorded at room temperature using TMS
as an internal reference and CDCl3 was used as solvent. The
13C NMR spectra were recorded in the proton decoupled mode
NMR spectra of the complexes 1–3 are included in the Sup-
porting Information. 1H, 13C, and 31P NMR chemical shifts are
given in Table 2.
Supporting Information (see footnote on the first page of this article):
NMR spectra of the three complexes; comparison of selected bond
lengths and angles.
3. Results and Discussion
3.1 Electronic Spectroscopy
1
3.4.1. H NMR Spectroscopy
Electronic spectra of the compounds show bands below
350 nm, which are due to intraligand π–π* transitions. Intense
bands in the 350–425 nm regions are due to charge transfer in
compounds 1–3.[17,18] In addition to the charge-transfer bands,
bands observed in the range of 425–650 nm are due to d–d
transitions. The two bands at 629 nm (λmax: 15898 cm–1, ε:
In the complexes, the allyl groups are non equivalent and
αЈ, βЈ, γЈ protons give only broad signals in the range: 1.25–
1.49 ppm indicating a substantial barrier to C–N(thioureide)
bond rotation. The observed deshielding of the αЈ-CH2 protons
in the compounds[21] is attributed to the shift of electron den-
sity on the sulfur (or the metal) atom through the thioureide π
375 L·mol–1·cm–1) and 480 nm (λmax
:
20833 cm–1 ε:
1125 L·mol–1·cm–1) correspond to dxy Ǟ dx2–y2 and dz2 Ǟ dx2– system. The α-CH protons of cyclohexyl ring adjacent to nitro-
transitions, respectively. The band position corresponding to gen atom undergo strong deshielding and are observed around
y2
the dxz Ǟ dx2–y2 and dyz Ǟ dx2–y2 transition would be between 4.4 ppm. The β, γ, δ-CH2 signals are observed as collapsed
the dxy Ǟ dx2–y2 (629 nm) and dz2 Ǟdx2–y2 (480 nm) transition. multiplets in the range of 1.64–2.72 ppm for all the com-
Z. Anorg. Allg. Chem. 2012, 1356–1361
© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.zaac.wiley-vch.de
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S. Srinivasan, K. Ramalingam, C. Rizzoli
ARTICLE
Table 1. Crystal data, data collection, and refinement parameters for compounds 1–3.
[Ni (achdtc)2]
[Ni(achdtc)(PPh)3(NCS)]
[Ni(achdtc)(PPh3)2]ClO40.5 EtOAc
Empirical formula
Formula weight
Color
C20H32 N2 Ni S4
487.4
green
C29H31 N2 Ni P S3
593.4
dark red
C48H50 Cl N Ni O5 P2 S2
941.1
red
Habit
Crystal system
Space group
block
orthorhombic
Pbca
plate
monoclinic
P21/c
needle
triclinic
P1
¯
Crystal dimension /mm
a /Å
b /Å
c /Å
α /°
β /°
0.16ϫ0.12ϫ0.10
11.195 (3)
12.228 (3)
17.214 (5)
90.00
90.00
90.00
2356.5(11)
4
1.374
0.38ϫ0.27ϫ0.08
19.4696(6)
8.7771(3)
19.6567(7)
90.00
118.1554(5)
90.00
2961.59(17)
4
1.331
0.941
1240
Mo-Kα (0.71073)
2.07–26.41
–24 Յ h Յ 24,
–10 Յ k Յ 10,
–24 Յ l Յ 24
6068
0.22ϫ0.25ϫ0.38
9.9314(5)
13.8546(8)
17.3732(10)
90.715(3)
95.635(3)
101.118(3)
2333.1(2)
2
1.340
0.677
984
Mo-Kα (0.71073)
1.50–28.00
–14 Յ h Յ 14,
–20 Յ k Յ 19,
–24 Յ l Յ 25
11108
γ /°
V /A3
Z
Dc /g·cm–3
μ /mm–1)
F(000)
λ /Å
1.186
1032
Mo-Kα (0.71073)
2.37–25.49
–13 Յ h Յ 13,
–14 Յ k Յ 14,
–20 Յ l Յ 20
23520
θ range /°
Index range
Reflections collected
Reflections [Fo Ͼ 2 σ(Fo)]
Number of parameters re-
fined
1453
5151
8187
124
325
568
Final R(obs. data), Rw (obs.
data and all data)
GOOF
0.0403, 0.1005, 0.1179
1.070
0.0276, 0.0730, 0.0762
1.066
0.0410, 0.0975, 0.1118
1.025
Residual electron density,
max., min.
0.436, –0.387
0.318, –0.255
0.479, –0.383
Table 2. NMR chemical shift of the complexes /ppm.
[Ni(achdtc)2]
Allyl
[Ni(achdtc)(PPh3)(NCS)]
[Ni(achdtc)(PPh3)2]ClO4
1H
13C
1H
13C
31P
1H
13C
31P
αЈ-CH2
βЈ-CH
1.25–1.45
(Collapsed multiplet) 47.7
1.20–1.45
(Collapsed mul-
tiplet)
1.24–1.49
Collapsed multiplet 45.07
48.28
γЈ-CH2
Cyclohexyl
α-CH
4.44–4.39
59.20
30.40
4.0–4.4
59.55
30.32
4.1–4.3
59.00
β-CH2
1.64–1.83
(Collapsed multiplet)
1.70–1.87
(Collapsed mul-
tiplet)
1.70–2.05
(Collapsed mul-
tiplet)
29.36–30.00
γ-CH2
25.49
25.21
207.67
25.38
25.25
204.16
26.98
26.56
202.31
δ-CH2
ϾN13CS
PPh3
7.28–7.78
119.54–
29.24 7.27–7.69
135.033
22.73
134.18
(Phenyl ring)
(Phenyl ring)
S13CN
143
1358
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© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Z. Anorg. Allg. Chem. 2012, 1356–1361

Planar NiS4, NiS2PN, and NiS2P2 Chromophores
pounds. For complexes 2 and 3 overlapping multiplets are ob- bond. The Ni–N distance [1.8670(15) Å] is quite short, show-
served in the region of 7.27–7.74 ppm due to aromatic protons ing the effective bonding between the nickel atom and NCS–.
involving P–H and H–H couplings.
The N–C–S bond angle is 179.3(2)°, indicating that it is almost
linear as observed earlier.[10]
The phenyl groups of triphenylphosphine show normal bond
parameters. The Ni–N–C angle [173.50(16)°] deviates from
linearity due to the bulky triphenylphosphine ligand. Com-
pound 2 contains four molecules in the asymmetric unit and
one of the molecules shows a significantly bent Ni–N–C angle:
165.30° due to packing requirements compared to the Ni–N–
C angle of 177.34° in another molecule.
The molecular structure of compound 3 is shown in Fig-
ure 3. The bite angle of the dithiocarbamate [78.36(2)°] shows
a significant decrease in 3, indicating the strong steric influ-
ence of two PPh3 groups. The observed Ni–S distances
[2.1997(6) Å and 2.2202(7) Å] show significant asymmetry.
Similarly, the Ni–P bonds show significant asymmetry
[2.2324(6) and 2.1963(6) Å] in the compound. The P–Ni–N
angle in compound 2 [90.06(5)°] is significantly smaller in
magnitude compared to P–Ni–P in compound 3 [98.37(2)°]
clearly indicating the play of steric force. Bond parameters
associated with the allyl, cyclohexyl, and phenyl groups were
the least affected on metal coordination.
A comparison of relevant bond lengths and angles of 1, 2,
and 3 shows that complex 2 is highly asymmetric with respect
to the Ni–S distances, attributed to the trans influences exerted
by PPh3 and NCS–. The thioureide C–N distances do not differ
significantly in the complexes. Decrease in the S–Ni–S bite
angles of 2 [78.80(16)°] and 3 [78.36(2)°] compared to com-
pound 1 [79.42(3)°] is due to the steric crowding around the
central metal atom. The P–Ni–S and S–Ni–S angles also re-
duced in magnitude due to the presence of bulky PPh3 in 2
and 3.
A comparison of bond parameters of related compounds
available on CSD shows the influence of substituents on the
arrangement around the metal.[23,24] Asymmetry in Ni–S bonds
was a maximum in [Ni(dtc) PPh3(NCS)] (where “dtc” is a ge-
neral notation for dithiocarbamates) compared to others due
to the operation of trans effect. Other bond parameters are
comparable. Distances between nickel atom and the S4 (S1,
S2, S1i, S2i) plane in 1 and S2NP (S1, S2, N2, P1) plane in 2
are less than 0.007 Å, clearly showing them to be of planar
arrangement. However, in 3, the distance between nickel atom
and the S2P2 (S1, S2, P1, P2) plane is 0.018 Å, much longer
than the distances observed in the other two compounds. The
observation indicates distortion of planar chromophore due to
steric effect.
13
3.4.2. C NMR Spectroscopy
13C chemical shifts of thioureide carbon atoms are corre-
lated to π bonding in the NCS2 fragment.[9] Generally higher
–
ν(C–N) values correlate with lower N13CS2 for d-block ele-
ments. The chemical shifts of the thioureide carbon atom
(N–13CS2) were observed at 207.67, 204.16, and 202.31 ppm
for complexes 1–3, respectively,[22] and is due to the allevia-
tion of excess electron density on nickel by phosphine, which
results in a drift of electron density towards the metal through
the thioureide bond from the nitrogen atom, supporting the
bidentate coordination of the dithiocarbamate with strong back
bonding. The thiocyanate influences a higher back bonding
ability, and hence compound 2 shows a signal in the upfield
region (δ =204.16 ppm). The thiocyanate carbon signal appears
at δ = 143 ppm as a weak signal. In the cyclohexyl ring, the
α-methylene carbon appears to be deshielded to a greater ex-
tent and signals are observed around 59 ppm for 1, 2, and 3.
The γ-CH2 carbon signals were observed around 25.0 ppm in
all the complexes. The β-CH2 carbon signals were observed
around 30.0 ppm for the three complexes.
3.4.3 31P NMR Spectroscopy
31P chemicals shifts are observed at δ = 29.24 and
22.73 ppm for 2 and 3, respectively, and are assigned to coor-
dinated phosphorus atoms. The free PPh3 resonates in the up
field region of –5.8 ppm.[23] Very high deshielding observed
for the coordinated phosphorus in compounds 2 and 3 com-
pared with the free phosphine indicates a strong synergic bond-
ing.
3.4.4 Crystal Structures
Crystal data, data collection, and refinement parameters are
given in Table 2. Selected bond parameters are given in
Table 3. The molecular structure of 1 is shown in Figure 1.
The observed distortion of the square-planar coordination
around nickel is attributed to the small bite angle of the dithio-
carbamate [79.42(3)°]. Planarity of the molecule is in keeping
with the observed diamagnetism of the complex. The C–S
bond lengths [1.728(4) and 1.718(3) Å] are shorter than the
typical single bond length of 1.81 Å and longer than the C=S
distance of 1.69 Å.
Compound 2 contains four discrete molecules per unit cell.
The molecular structure is shown in Figure 2. The bite angle
of the dithiocarbamate [78.80(16)°] is lower than that observed
4. Conclusions
Synthesis and spectral characterization of [Ni(achdtc)2] (1),
in 1 due to the steric influence exerted by PPh3. The observed [Ni(achdtc)(PPh3)(NCS)] (2), [Ni(achdtc)(PPh3)2]ClO4·0.5EtOAc
difference in the Ni–S distances [2.1674(5) Å (trans to NCS) (3) revealed their composition, contribution of thioureide bond,
and 2.2299(5) Å (trans to PPh3)] is attributed to the difference and planarity of the compounds. The 31P NMR spectra of com-
in the trans influencing properties of NCS and PPh3. PPh3 pounds 2 and 3 showed a significant chemical shift of the coor-
being a good π acceptor has a greater trans influence and hence dinated phosphorus compared to that of free PPh3. Single crys-
the Ni–S bond trans to PPh3 is longer than the other Ni–S tal X-ray structure determination of the compounds confirmed
Z. Anorg. Allg. Chem. 2012, 1356–1361
© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.zaac.wiley-vch.de
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S. Srinivasan, K. Ramalingam, C. Rizzoli
ARTICLE
Table 3. Selected bond lengths /Å and bond angles /° for 1–3.
[Ni (achdtc)2] (1)
[Ni(achdtc)(PPh3)(NCS)] (2)
[Ni(achdtc)(PPh3)2]ClO40.5 EtOAc (3)
Ni(1)–S(1)
Ni(1)–S(2)
S(1) –C(1)
S(2)–C(1)
N(1)–C(1)
N(1)–C(5)
N(1)–C(2)
2.2080(10)
2.1897(11)
1.728(4)
1.718(3)
1.316(4)
1.482(4)
1.489(4)
Ni(1)–S(1)
Ni(1)–S(2)
S(1)–C(1)
S(2)–C(1)
C(1)–N(1)
Ni(1)–N(2)
Ni(1)–P(1)
N(1)–C(2)
N(1)–C(5)
2.1674(5)
2.2299(5)
1.7277(15)
1.7115(17)
1.316(2)
1.8670(15)
2.1942(4)
1.483(4)
Ni(1)–S(1)
Ni(1)–S(2)
S(1)–C(1)
S(2)–C(1)
C(1)–N(1)
Ni(1)–P(1)
Ni(1)–P(2)
N(1)–C(2)
N(1)–C(5)
2. 2202(7)
2.1997(6)
1.716(2)
1.725(2)
1.308(3)
2.2324(6)
2.1963(6)
1.481(3)
1.482(3)R
1.486(4)
C(1)–S(1)–Ni(1)
C(1)–S(2)–Ni(1)
S(2)–Ni(1)–S(1)
S(2)–C(1)–S(1)
N(1)–C(1)–S(2)
N(1)–C(1)–S(1)
C(1)–N(1)–C(2)
C(1)–N(1)–C(5)
C(5)–N(1)–C(2)
85.18(12)
85.99(12)
79.42(3)
109.22(19)
125.0(3)
125.8(3)
118.8(3)
121.4(3)
119.4(3)
C(1) –S(1)–Ni(1)
C(1)–S(2)–Ni(1)
S(2)–Ni(1)–S(1)
S(2)–C(1)–S(1)
N(1)–C(1)–S(2)
N(1)–C(1)–S(1)
N(2)–Ni(1)–S(1)
N(2)–Ni(1)–P(1)
S(1)–Ni(1)–P(1)
87.09(6)
85.50(5)
C(1)–S(1)–Ni(1)
S(2)–Ni(1)–S(1)
S(2)–C(1)–S(1)
N(1)–C(1)–S(2)
N(1)–C(1)–S(1)
C(1)–N(1)–C(2)
C(1)–N(1)–C(5)
C(2)–N(1)–C(5)
P(1)–Ni(1)–P(2)
86.27(8)
78.36(2)
78.80(16)
108.53(9)
126.24(12)
125.22(12)
172.32(5)
90.06(5)
108.50(12)
126.01(17)
125.49(18)
119.8(2)
120.53(19)
119.47(19)
98.37(2)
95.62(17)
Figure 1. Molecular structure of [Ni(achdtc)2] [Symmetry code:
(i) –x, 1–y, –z].
Figure 3. Molecular structure of [Ni(achdtc)(PPh3)2]ClO4·0.5EtOAc.
from a planar NiS4 chromophore to distorted planar NiS2PN,
NiS2P2 chromophores. The observed distortion from planar to
tetrahedral arrangement is influenced by the presence of the
bulky triphenylphosphine ligand.
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Received: March 6, 2012
Published Online: July 10, 2012
Z. Anorg. Allg. Chem. 2012, 1356–1361
© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.zaac.wiley-vch.de
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