Highly soluble sulfur-rich [Ni(L)(siS3)] complexes containing the new ligand Bis(2-mercapto-3-trimethylsilylphenyl) sulfide(2-) (siS32-)

Article abstract of DOI:10.1002/1099-0682(200208)2002:8<2138::AID-EJIC2138>3.0.CO;2-H

The new organosulfur ligands ^siS₃-H₂ [^siS₃^2- = bis(2-mercapto-3-trimethylsilylphenyl) sulfide(2-)] and ^caS₃-H₂ [^caS₃^2- = bis(2-mercapto-3-carboxyphenyl) sulfide(2-)] were synthesized from ^HS₃-H₂ [^HS₃^2- = bis(2-mercaptophenyl) sulfide(2-)], n-butyllithium, and Me₃SiCl or CO₂/H⁺. Reaction of ^siS₃-H₂ with Ni(ac)₂·4H₂O gave the air-stable and well-soluble trinuclear complex [Ni(^siS₃)]₃ (1) whose structure was determined by X-ray crystallography. Reactions of complex 1 with nucleophiles L [L = PR₃ (R = nPr, Ph, Cy), N₂H₄, StBu^-, and Cl^-] yielded the corresponding neutral or anionic complexes, which were isolated as [Ni(PR₃)(^siS₃)] [R = nPr (2), Ph (3), Cy (4)], Bu₄N[Ni(Cl)(^siS₃)] (5), Bu₄N-[Ni(StBu)(^siS₃)] (6), and [Ni(N₂H₄)(^siS₃)] (8). The azido complex Et₄N[Ni(N₃)(^siS₃)] (7) was prepared from Me₃SiN₃ and the precursor chloro complex Et₄N[Ni(Cl)(^siS₃)]. Reaction of 1 with NH₃ yielded labile [Ni(NH₃)(^siS₃)] (9), which was characterized in solution by ¹H and ¹³C NMR spectroscopy. Analogously, 1 reacts with nicotinamide (NA) or diethylnicotinamide (NAEt₂) to give, from equilibrium reactions, the corresponding mononuclear [Ni(L)(^siS₃)] complexes with L = NA, NAEt₂. X-ray structure determinations showed that 1, 3, 4, 5, and 7 all exhibit tetrahedrally distorted planar [Ni(L)(^siS₃)] fragments. Complex 7 is the first structurally characterized azidonickel complex with a coligand having exclusively sulfur donors. Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002.

Full text of DOI:10.1002/1099-0682(200208)2002:8<2138::AID-EJIC2138>3.0.CO;2-H

FULL PAPER
Highly Soluble Sulfur-Rich [Ni(L)(siS3)] Complexes Containing the New
2؊ [‡]
Ligand Bis(2-mercapto-3-trimethylsilylphenyl) Sulfide(2؊) (siS3
)
Dieter Sellmann*,*[a] Raju Prakash,[a] Franz Geipel,[a] and Frank W. Heinemann[a]
Dedicated to Professor Joachim Strähle on the occasion of his 65th birthday
Keywords: Nickel / S ligands / Silicon / Hydrazine / Nicotinamide
2−
The new organosulfur ligands siS3-H2 [siS3 = bis(2-mer- the precursor chloro complex Et4N[Ni(Cl)(siS3)]. Reaction of
capto-3-trimethylsilylphenyl) sulfide(2−)] and caS3-H2 1 with NH3 yielded labile [Ni(NH3)(siS3)] (9), which was char-
2−
1
[
caS3 = bis(2-mercapto-3-carboxyphenyl) sulfide(2−)] were acterized in solution by H and 13C NMR spectroscopy. Ana-
2−
synthesized from HS3-H2 [HS3 = bis(2-mercaptophenyl) logously, 1 reacts with nicotinamide (NA) or diethylnicotin-
sulfide(2−)], n-butyllithium, and Me3SiCl or CO2/H+. Reac- amide (NAEt2) to give, from equilibrium reactions, the corres-
tion of siS3-H2 with Ni(ac)2·4H2O gave the air-stable and ponding mononuclear [Ni(L)(siS3)] complexes with L = NA,
well-soluble trinuclear complex [Ni(siS3)]3 (1) whose struc- NAEt2. X-ray structure determinations showed that 1, 3, 4, 5,
ture was determined by X-ray crystallography. Reactions of and 7 all exhibit tetrahedrally distorted planar [Ni(L)(siS3)]
complex 1 with nucleophiles L [L = PR3 (R = nPr, Ph, Cy), fragments. Complex 7 is the first structurally characterized
N2H4, StBu−, and Cl−] yielded the corresponding neutral or azidonickel complex with a coligand having exclusively sul-
anionic complexes, which were isolated as [Ni(PR3)(siS3)] [R = fur donors.
nPr (2), Ph (3), Cy (4)], Bu4N[Ni(Cl)(siS3)] (5), Bu4N-
[Ni(StBu)(siS3)] (6), and [Ni(N2H4)(siS3)] (8). The azido com- ( Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany,
plex Et4N[Ni(N3)(siS3)] (7) was prepared from Me3SiN3 and 2002)
Introduction
The discovery of nickel cysteinate units in the active cen-
ters of [NiFe] hydrogenases[1Ϫ3] and CO dehydrogenases[4]
accounts for much of the current interest in nickel thiolate
The unique reactivity of these complexes could be traced
back to the formation of [Ni(LЈ)(L)(HS3)] intermediates
complexes. Numerous efforts have been made in order to
(LЈ ϭ H2, CO, CO2, SO2) exhibiting five-coordinate nickel
find low molecular weight complexes that model the nickel
centers. The heterolysis of H2 catalyzed by
cysteinate site and the reactivity of these enzymes.[5Ϫ10] In
[Ni(NHPnPr3)(HS3)][14] prompted us to investigate the ac-
this context, we have recently found that [Ni(L)(HS3)] com-
tivation of H2 by other [Ni(L)(HS3)] complexes, and a par-
plexes containing the [Ni(HS3)] complex fragment[11Ϫ13]
ticularly intriguing goal was to use H2 for intramolecularly
hydrogenating ligands which can exist in the hydro and de-
2Ϫ
HS3 ϭ bis(2-mercaptophenyl) sulfide(2Ϫ) and L ϭ
Ϫ
NHPnPr3 or N(SiMe3)2 as coligands exhibit reactions rel-
hydro form such as the nicotinamide/dihydronicotinamide
evant to [NiFe] hydrogenases and CO dehydrogenases, e.g.,
couple (NA/NAH2) [Equation (1)].
catalysis of H2/D2O exchange[14] and deoxygenation of CO,
CO2, and SO2.[15]
[‡]
Transition Metal Complexes with Sulfur Ligands, 154. Part 153:
D. Sellmann, F. Geipel, F. Lauderbach, F. W. Heinemann,
Angew. Chem. 2002, 114, 654Ϫ656; Angew. Chem. Int. Ed.
2002, 41, 632Ϫ634.
(1)
[a]
Institut für Anorganische Chemie der Universität Erlangen-
Nürnberg,
Egerlandstrasse 1, 91058 Erlangen, Germany
Fax: (internat.) ϩ 49-(0)9131/852-7367
E-mail: sellmann@anorganik.chemie.uni-erlangen.de
The prerequisite for corresponding experiments were [Ni-
(NA)(HS3)] complexes. Although NA complexes are known
2138
 WILEY-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002 1434Ϫ1948/02/0808Ϫ2138 $ 20.00ϩ.50/0 Eur. J. Inorg. Chem. 2002, 2138Ϫ2146

Highly Soluble Sulfur-Rich [Ni(L)(siS3)] Complexes
FULL PAPER
to exist,[16] they could not be obtained with [Ni(HS3)] frag-
In an analogous reaction, treatment of the heterogeneous
ments. A major obstacle was the fact that [Ni(L)(HS3)] com- mixture obtained from HS3-H2 and butyllithium with gas-
plexes frequently are only very sparingly soluble in common eous CO2 and subsequent acidification yielded caS3-H2.
organic solvents. A prime example is the trinuclear parent Upon recrystallization from acetone, it was obtained in
complex [Ni(HS3)]3 which is practically insoluble in all solv- green-yellow needles.
ents. Due to this we have now tried to obtain better soluble
The 1H NMR spectrum of siS3-H2 exhibits three mul-
derivatives by introducing SiMe3 or CO2H substituents into tiplets for the six aromatic protons, a broad singlet for the
the HS3-H2 ligand. This paper reports on the synthesis of two thiols and a sharp singlet for the SiMe3 protons. The
two new ligands, and a series of nickel complexes with the 1H NMR spectrum of caS3-H2 shows a similar pattern for
2Ϫ
SiMe3 derivative siS3 ϭ bis(2-mercapto-3-trimethylsilyl- the aromatic protons and broad peaks at δ ϭ 7.28 and
phenyl) sulfide(2Ϫ).
11.85 ppm for the SH and CO2H protons. It is worth noting
that the SH proton shift is influenced by the benzene ring
substituents and appears δ ഠ 4.5 ppm at lower field in caS3-
si
H2 than in S3-H2. The number and shift of the 13C reson-
Results and Discussion
si
ances in the 13C{1H} NMR spectra of S3-H2 and caS3-H2
Synthesis of SiMe3 and CO2H Derivatives of HS3-H2
established that both of the ligands possess C2 symmetry
The new ligands siS3-H2 and caS3-H2, where ‘‘si’’ and
‘‘ca’’ denote SiMe3 and CO2H substituents in the ortho po-
sition to the SH functions, were obtained in one-pot reac-
tions according to Scheme 1.
in solution.
Synthesis, Reaction, and Characterization of Complexes
with [Ni(siS3)] Fragments
The starting complex [Ni(siS3)]3 (1) was formed in a
si
straightforward reaction from Ni(ac)2·4H2O and S3-H2 in
THF/MeOH mixtures. A dark brown solution resulted
from which 1 was obtained analytically pure and in high
yield (87%). Complex 1 is stable towards air and moisture
for extended periods of time and soluble in many common
organic solvents, e.g., THF, CH2Cl2, acetone, Et2O, toluene,
hexane, MeCN, DMF, DMSO. In MeOH or pentane, 1 is
sparingly soluble. Complex 1 fulfilled one of the expecta-
tions connected with the synthesis of siS3-H2, showing good
solubility in organic solvents in which the parent complex
[Ni(HS3)]3 proved insoluble. The 1H and 13C{1H} NMR
spectra of 1 were compatible with the trinuclear structure
indicated in Scheme 2. This structure was confirmed by a
single-crystal X-ray structure determination.
Subsequent experiments were aimed at cleaving trinuclear
[Ni(siS3)]3 and probing the coordination of σ and σ-π li-
gands to the [Ni(siS3)] fragment. Scheme 2 summarizes the
reactions of 1 yielding mononuclear [Ni(L)(siS3)] complexes.
Scheme 1. Synthesis of siS3-H2 and caS3-H2
The synthesis route made use of previous results obtained Treatment of 1 with phosphanes gave [Ni(PR3)(siS3)] with
by other authors and us showing that aromatic sulfur com- R ϭ n-Pr (2), Ph (3), and Cy (4). The reactions could be
pounds such as S(C6H5) can be lithiated with excess butylli- monitored by the practically instantaneous color change of
thium.[17,11]
the THF solution from red-brown to yellow-red or orange,
Treatment of HS3-H2 with 4 equiv. of nBuLi in a hexane/ and they took place much faster than the analogous reac-
TMEDA mixture (TMEDA ϭ N,NЈ-tetramethylethylenedi- tions of the parent [Ni(HS3)]3 complex with the phosphanes.
amine) yielded a white to yellow precipitate. This precipitate The phosphane derivatives 2, 3, and 4 proved inert with
was not characterized in detail, and its structure, indicated regard to substitution of the phosphane ligands.
in Scheme 1, was concluded only from subsequent reac-
Substitution-labile [Ni(L)(siS3)] complexes were obtained
tions. Treatment of the heterogeneous mixture with 4 equiv. with L ϭ ClϪ and StBuϪ. Treatment of 1 with an equimolar
of SiMe3Cl, acidification with hydrochloric acid, and ex- amount of Bu4NCl yielded dark purple needles of Bu4N-
traction with Et2O yielded a product in which the thiol [Ni(Cl)(siS3)] (5). With Bu4NStBu, brown microcrystals of
functions of siS3-H2 were still partially silylated by the Bu4N[Ni(StBu)(siS3)] (6) were obtained. The chloro derivat-
SiMe3 groups. These SiMe3 groups were removed in boiling ive [Ni(Cl)(siS3)]Ϫ enabled the synthesis of the azido com-
MeOH (yielding Me3SiOMe3) and the resultant siS3-H2 was plex, which was not accessible directly from 1. For this pur-
obtained as a brown viscous oil. It was identified by ele- pose
1
was first treated with Et4NCl to give
mental analysis and spectroscopic methods, and could be Et4N[Ni(Cl)(siS3)] in situ. Subsequent addition of Me3SiN3
used for synthesis of complexes without further purifica- yielded Et4N[Ni(N3)(siS3)] (7) which was isolated as violet
tion.
needles. Complexes 5 and 7 demonstrated that typical σ-
Eur. J. Inorg. Chem. 2002, 2138Ϫ2146
2139

D. Sellmann, R. Prakash, F. Geipel, F. W. Heinemann
FULL PAPER
ative 9 showed that the resulting mononuclear complexes
may be labile. Nevertheless, much effort was spent on the
synthesis of [Ni(siS3)] complexes with nicotinamide (NA) or
nicotinamide derivatives (NAR2) as coligands. The aim of
these efforts was to form species that could be hydrogenated
by molecular hydrogen according to Equation (2).
(2)
In this reaction we wanted to make use of the heterolytic
cleavage of H2 observed to be catalyzed by
[Ni(NHPnPr3)(HS3)] in order to achieve the chemical ‘‘stor-
age’’ of H2 characteristic for the NAD/NADH couple. Tak-
ing the pKa values of different nicotinamide derivatives into
account,[18] we have focused on the coordination of either
NA or diethylnicotinamide (NAEt2), and treated 1 or the
substitution-labile complexes 5 and 6 with varying amounts
of NA or NAEt2, ranging from 1:1 ratios to a large excess
of NA or NAEt2. In these experiments, mixtures of 1, the
nicotinamide [Ni(L)(siS3)] complexes and uncoordinated
nicotinamide derivatives were obtained that could not be
separated. The color change of the THF reaction solutions
from dark-brown to red indicated that a reaction took
place. Using the SiMe3 signals as a spectroscopic probe en-
Scheme 2. Synthesis and reactions of [Ni(siS3)]3 complexes
donor ligands can form stable adducts with [Ni(siS3)] frag-
ments. With hydrazine, 1 could directly be cleaved to give
dark-red [Ni(N2H4)(siS3)] (8). The analogous reaction with
NH3 yielded a very labile species that could be generated
and characterized only in situ in an NMR tube. All at-
tempts to isolate [Ni(NH3)(siS3)] in the solid state re-
mained unsuccessful.
1
abled us to monitor the reaction course by H NMR spec-
troscopy. Figure 1 illustrates the reaction between 1 and
NA. Figure 1 (a) shows the two SiMe3 singlets of the start-
ing complex 1 at δ ϭ 0.57 and 0.09 ppm. Addition of 1
equiv. of NA gives rise to a new SiMe3 singlet at δ ϭ
0.33 ppm indicating the formation of [Ni(NA)(siS3)], while
the intensity of the two signals of 1 decreases. The intensity
of the signal at δ ϭ 0.33 ppm increases when more NA is
added. Figure 1 (c) demonstrates that at a 1:10 ratio of 1/
NA, which equals an approximately threefold excess of NA,
complex 1 has been converted almost entirely into the deriv-
ative [Ni(NA)(siS3)]. Analogous spectra were observed for
the reaction between 1 and NAEt2. However, attempts to
Hydride or CO derivatives of [Ni(siS3)] could not be ob-
tained. At high pressures of CO (100 bar), minor amounts
of 1 were converted into Ni(CO)4 in the course of 10 d. The
resulting Ni(CO)4 could be isolated by fractional condensa-
tion and was identified by its ν(CO) IR band at 2040
cmϪ1 [10e]
.
All of the complexes 1Ϫ9 proved to be very soluble in
THF, CH2Cl2, acetone, toluene, MeCN, DMF, and DMSO.
As judged by their NMR spectra, they are diamagnetic. The
1H NMR spectra of all mononuclear complexes 2Ϫ9 show
a typical splitting pattern for the aromatic protons, con-
sisting of three multiplets, and an SiMe3 singlet. The intense
SiMe3 singlet is also well suited for probing the purity of the
1
complexes. In addition, the SiMe3 singlet in the H NMR
spectrum indicates Cs symmetry of the [Ni(siS3)] fragments
in 2Ϫ9. This is corroborated by 13C and 31P NMR spectra
as well as by the X-ray structure determination of 3, 4, 5,
and 7. The azido complex 7 shows a characteristic ν(N3)
band at 2037 cmϪ1in the IR spectrum, in the solid state as
well as in CH2Cl2 solution. It is noted that 7 is the first
structurally characterized azidonickel complex with a col-
igand exclusively having sulfur donors.
The formation and characterization of the complexes 7,
Figure 1. SiMe3 region of 1H NMR spectra of [Ni(siS3)]3 in
[D8]THF (a) before and (b) after addition of 1 equiv. and (c) after
8, and also 9 proved the capability of the [Ni(siS3)] fragment
to bind σ-donor amine ligands, though the ammonia deriv- addition of 10 equiv. of nicotinamide
2140
Eur. J. Inorg. Chem. 2002, 2138Ϫ2146

Highly Soluble Sulfur-Rich [Ni(L)(siS3)] Complexes
FULL PAPER
crystallize the [Ni(NA)(siS3)] or [Ni(NAEt2)(siS3)] com-
plexes from such solutions or to remove the excess of NA
or NAEt2 by extraction were unsuccessful. In the latter
case, the starting complex 1 was regenerated. This clearly
demonstrates that the reaction between 1 and NA or NAEt2
is an equilibrium reaction [Equation (3)].
(3)
In this regard, the reactions between 1 and NA or NAEt2
compare with the reversible formation of [Ni(NH3)(siS3)]
from 1 and NH3. Because it proved impossible to isolate
[Ni(NA)(siS3)] or [Ni(NAEt2)(siS3)] in a pure state, mixtures
of the complexes and the respective free NA or NAEt2 were
treated with molecular hydrogen in an autoclave at pres-
sures ranging from 10 to 100 bar. However, in no case could
the formation of dihydronicotinamide derivatives be ob-
served. The most plausible explanation is that [Ni-
(NA)(siS3)] and [Ni(NAEt2)(siS3)] complexes, unlike the
phosphorane imine complex [Ni(NHPnPr3)(HS3)], do not
catalytically heterolyze H2 or if they do, do not enable the
necessary subsequent hydride transfer from the nickel atom
to the NA ligand.
X-ray Structure Determinations
Crystal structures of [Ni(siS3)]3·0.5CD2Cl2 (1·0.5CD2Cl2),
[Ni(siS3)]3·2THF·3MeOH (1·2THF·3MeOH), [Ni(PPh3)-
(siS3)] (3), [Ni(PCy3)(siS3)]·2CDCl3 (4·2CDCl3), Bu4N-
Figure 3. ORTEP diagrams of (a) [Ni(PPh3)(siS3)] (3), (b)
[Ni(PCy3)(siS3)]·2CDCl3 (4·2CDCl3), (c) Bu4N[Ni(Cl)(siS3)]·
0.625THF·0.375Et2O
(5·0.625THF·0.375Et2O),
and
(d)
Et4N[Ni(N3)(siS3)]·THF (7·THF) (50% probability ellipsoids;
hydrogen atoms, solvent molecules, and cations omitted)
[Ni(Cl)(siS3)]·0.625THF·0.375Et2O
(5·0.625THF·0.375
Et2O), Et4N[Ni(N3)(siS3)]·THF (7·THF) were determined
by X-ray structure analysis. Figures 2 and 3 depict ORTEP
diagrams of the structures, Tables 1 and 2 list selected dis-
tances and angles.
Table 1. Selected distances [pm] and angles [°] for
[Ni(siS3)]3·0.5CD2Cl2 (1·0.5CD2Cl2) (three independent [Ni(siS3)]
units; the columns refer to: a: Ni1, S1, S2, S3; b: Ni2, S4, S5, S6;
c: Ni3, S7, S8, S9)
The unit cells of all compounds contain discrete molec-
ules or ions. The unit cells of 3 and 5 each contain two
Compound
[Ni(siS3)]3 (1)
b
a
c
Ni1ϪS1
Ni1ϪS2
Ni1ϪS3
Ni1ϪS9
Ni1···Ni2
S3···S9
S1ϪNi1ϪS2
S1ϪNi1ϪS3
S1ϪNi1ϪS9
S2ϪNi1ϪS3
S2ϪNi1ϪS9
S3ϪNi1ϪS9
Ni1ϪS3ϪNi2
215.6(1)
214.4(1)
219.4(1)
219.8(1)
334.6(2)
305.8(1)
91.12(4)
159.82(4)
95.84(3)
88.77(3)
167.50(4)
88.25(3)
99.00(4)
214.9(1)
214.4(1)
220.2(1)
220.6(1)
321.3(6)
312.1(4)
89.74(4)
162.99(4)
93.42(4)
89.61(3)
169.90(4)
90.15(3)
93.29(3)
214.8(1)
214.3(1)
222.2(1)
221.7(1)
327.5(6)
318.7(3)
90.89(3)
158.06(4)
95.25(3)
87.46(3)
165.23(4)
91.75(3)
95.61(3)
crystallographically independent molecules, exhibiting es-
sentially identical bond lengths and angles, of which only
one molecule is shown in Figure 2. All compounds exhibit
four-coordinate nickel centers in a strongly tetrahedrally
distorted planar coordination. The tetrahedral distortion
Figure 2. ORTEP diagram of [Ni(siS3)]3·0.5CD2Cl2 (1·0.5CD2Cl2)
(50% probability ellipsoids; hydrogen atoms and solvent molecule
omitted)
Eur. J. Inorg. Chem. 2002, 2138Ϫ2146
2141

D. Sellmann, R. Prakash, F. Geipel, F. W. Heinemann
FULL PAPER
[Ni(siS3)] fragments that are well soluble in common solv-
ents and more reactive than the [Ni(HS3)] parent complexes.
These objectives have been reached and, unlike the
[Ni(HS3)] parent fragment, the [Ni(siS3)] complex fragment
has been proved to bind even nicotinamide or diethylnicoti-
namide, though only in equilibrium reactions. Attempts to
hydrogenate the nicotinamide complexes in solution to give
dihydronicotinamide derivatives, however, remains unsuc-
cessful.
Table 2. Selected distances [pm] and angles [°] for [Ni(PPh3)(siS3)]
(3),
[Ni(PCy3)(siS3)]·2CDCl3
(4·2CDCl3),
Bu4N[Ni(Cl)-
and
(siS3)]·0.625THF·0.375Et2O
(5·0.625THF·0.375Et2O),
Et4N[Ni(N3)(siS3)]·THF (7·THF)
Compound
3
4
5
7
(NiϪPPh3) (NiϪPCy3) (NiϪCl) (NiϪN3)
Ni1ϪS1
Ni1ϪS2
Ni1ϪS3
Ni1ϪL
N1ϪN2
N2ϪN3
S1ϪNi1ϪS2
S1ϪNi1ϪS3
S1ϪNi1ϪL
S2ϪNi1ϪS3
S2ϪNi1ϪL
S3ϪNi1ϪL
Ni1ϪN1ϪN2
N1ϪN2ϪN3
216.5(3)
213.0(4)
219.7(4)
221.3(4)
217.3(1)
213.5(1)
215.3(2)
221.7(2)
218.3(3)
208.7(2)
217.3(3)
220.3(2)
216.9(2)
211.1(2)
218.2(2)
191.3(4)
118.5(6)
115.8(6)
89.78(5)
167.31(6)
91.4(2)
89.15(5)
173.4(2)
91.1(2)
121.2(3)
175.6(6)
Experimental Section
90.1(2)
164.2(2)
90.3(2)
86.0(2)
176.9(2)
94.5(2)
88.14(4)
160.00(6)
93.35(4)
90.00(5)
165.05(5)
93.54(4)
88.1(1)
162.3(1)
93.0(1)
90.3(1)
165.3(1)
93.1(1)
General Methods: Unless stated otherwise, all reactions and manip-
ulations were carried out under nitrogen at room temperature using
standard Schlenk techniques. All solvents were dried and distilled
before use. As far as possible, reactions were monitored by IR or
NMR spectroscopy. Physical measurements were carried out with
the following instruments: IR (KBr discs or CaF2 cuvettes, solvent
bands were compensated), PerkinϪElmer 983, 1620 FT-IR and
16PC FT-IR; NMR: Jeol JMM-GX 270, Jeol JMM-EX 270, and
Lambda LA 400 with the residual protio-solvent signal used as an
internal reference. Chemical shifts are quoted in the δ scale (down
field shifts are positive) relative to tetramethylsilane (1H, 13C{1H}
NMR) or 85% H3PO4 (31P{1H} NMR). Mass spectra: Jeol
MSTATION 700 spectrometer. Elemental analyses: Carlo Erba EA
1106 or 1108 analyzer. Me3SiCl, Me3SiN3, HStBu, Bu4NCl,
Et4NCl, N2H4 (1  solution in THF), nicotinamide, N,N-diethylni-
cotinamide were purchased from either Aldrich or Fluka. HS3-H2
was prepared as described in the literature.[11]
can be traced back to the sp3-hybridized thioether S donors
of the siS3 ligand, leading to a butterfly-like shape of the
resulting [Ni(siS3)] fragments. The characteristic topology of
si
the S3 ligand also causes the NiϪS(thioether) distances to
always be shorter than the NiϪS(thiolate) distances. In this
respect, [Ni(siS3)] complexes are analogous to [Ni(HS3)]
complexes that contain the HS3 parent ligand and have been
described previously.[11Ϫ13]
Trimerization of [Ni(siS3)] fragments by thiolate bridges
leads to 1. Complex 1 contains a cyclohexane-like six-mem-
bered [NiS]3 ring with a chair conformation, and the struc-
ture of 1 parallels that of the parent complex [Ni(HS3)]3.[12]
All bridging NiϪS(thiolate) distances in the six-membered
[NiS]3 ring, ranging from 219.4(1) to 222.2(1) pm, are dis-
tinctly longer than the terminal NiϪS(thiolate) distances
[214.3(1) to 215.6(1) pm]. This elongation of bridging NiϪS
distances rationalizes the ready dissociation of 1 in solution
when treated with suitable monodentate ligands.
In the complexes 3, 4, 5, and 7, the fourth coordination
site of the [Ni(siS3)] fragments is occupied by PPh3, PCy3,
ClϪ, or N3Ϫ. The distances and angles in 3, 4, 5, and 7 lie
in the range observed for analogous [Ni(L)(HS3)] complexes,
and thus far, show no anomalies.[10Ϫ15] For example, the
NiϪS(thioether) distance is always shorter than the
NiϪS(thiolate) distances and the [Ni(siS3)] fragments ex-
hibit their typical butterfly shape. The NϪN distances
[118.5(6) and 115.8(6) pm] and NiϪN1ϪN2 angle
[121.2(3)°] in 7 are characteristic for azide complexes in
which the azide ligand binds end-on as a σ-donor to the
metal atom.[19,20]
siS3-H2: With continuous vigorous stirring under argon, nBuLi in
hexane (2.5 , 45 mL, 112.51 mmol) was slowly added to a suspen-
sion of HS3-H2 (6.49 g, 25.92 mmol) in hexane (200 mL) at Ϫ78 °C.
After addition of TMEDA (31 mL, 206.01 mmol), the temperature
was raised gradually to 25 °C. Stirring was continued for another
72 h, in the course of which the color of the suspension turned
from white to yellow. This suspension was cooled to Ϫ78 °C, Si-
Me3Cl (15 mL, 118.03 mmol) was added slowly, and stirring was
continued for 1 h at Ϫ78 °C and 24 h at 25 °C, in the course of
which the color of the suspension changed back to white. H2O
(50 mL) was added, and all volatile components were removed in
vacuo. A red-brown highly viscous residue remained which was dis-
solved in Et2O (500 mL). The resulting Et2O solution was washed
by extraction with hydrochloric acid (5%, 3 ϫ 200 mL) and a satur-
ated NaCl/H2O solution (2 ϫ 100 mL), and dried with solid
Na2SO4. Removal of all volatile components in vacuo yielded a
yellow-red viscous residue, which was dissolved in MeOH (150 mL)
and heated to reflux for 12 h. Removal of volatile components in
vacuo gave a red-brown viscous oil of siS3-H2, which could be used
for the synthesis of complexes without further purification. Yield:
9.55 g (93%). C18H26S3Si2 (394.78): calcd. C 54.76, H 6.65, S 24.39;
found C 55.01, H 6.58, S 24.28. MS (FD, THF): m/z ϭ 394 [Mϩ].
1H NMR (269.7 MHz, C6D6): δ ϭ 7.23 (d, 2 H, C6H3), 7.10 (d, 2
H, C6H3), 6.78 (t, 2 H, C6H3), 4.61 (br, 2 H, SH), 0.35 (s, 18 H,
SiMe3) ppm. 13C{1H} NMR (67.8 MHz, C6D6): δ ϭ 141.3, 140.9,
134.6, 134.4, 133.0, 126.3 (C6H3), Ϫ0.2 (SiMe3) ppm.
Conclusion
caS3-H2: To a suspension of HS3-H2 (7.05 g, 28.17 mmol) in hexane
(150 mL), nBuLi in hexanes (2.5 , 45 mL, 112.51 mmol) was ad-
ded slowly at Ϫ78 °C. Under vigorous stirring, TMEDA (31 mL,
206.01 mmol) was added and the temperature gradually raised to
This work describes the synthesis of the new ligands siS3-
H2 and caS3-H2 and a series of [Ni(L)(siS3)] complexes. The
major aim of the investigations was to find complexes with 25 °C. The mixture was stirred for another 72 h, in the course of
2142 Eur. J. Inorg. Chem. 2002, 2138Ϫ2146

Highly Soluble Sulfur-Rich [Ni(L)(siS3)] Complexes
FULL PAPER
which the color of the suspension turned from white to yellow. This
tone): δ ϭ 7.94 (d, 2 H, C6H3), 7.83Ϫ7.52 (m, 15 H, C6H5), 7.28
suspension was cooled down again to Ϫ78 °C, CO2 was bubbled (d, 2 H, C6H3), 7.04 (t, 2 H, C6H3), 0.12 (s, 18 H, SiMe3) ppm.
3
through for 30 min under vigorous stirring and the mixture was
13C{1H} NMR (67.8 MHz, [D6]acetone): δ ϭ 159.5 (d, JPC
ϭ
gradually warmed to 0 °C in the course of 1 h. All volatile compon-
ents were removed in vacuo. The resulting mixture was treated with (d, JPC ϭ 47.4 Hz) 129.6, 129.1 (d, JPC ϭ 10.2 Hz), 122.7 [C6H3,
14 Hz), 143.0, 135.4, 135.3 (d, JPC ϭ 10.8 Hz), 133.3, 131.7, 130.4
1
cold water (50 mL) and concentrated hydrochloric acid (70 mL).
The resulting mixture was extracted with a mixture of Et2O
(100 mL) and THF (30 mL). The extract was dried with Na2SO4
and the solvents were evaporated to give a dry pale yellow residue.
This was recrystallized from acetone (60 mL) at Ϫ20 °C. Green
yellow needles precipitated, which were separated after 2 d, washed
with cold acetone (10 mL, 0 °C) and dried in vacuo. Yield: 4.83 g
(51%). C14H10O4S3 (338.43): calcd. C 49.69, H 2.98, S 28.42; found
C 49.99, H 3.36, S 27.78. MS (FD, THF): m/z ϭ 338 [Mϩ]. IR
(KBr): ν˜ ϭ 2980 [ν(OH)], 2484 [ν(SH)], 1652 [ν(COOH)] cmϪ1. 1H
NMR (399.7 MHz, [D8]THF): δ ϭ 11.85 (br, 2 H, COOH), 8.06
(d, 2 H, C6H3), 7.30 (d, 2 H, C6H3), 7.28 (s, 2 H, SH), 7.08 (t, 2
H, C6H3) ppm. 13C{1H} NMR (100.4 MHz, [D8]THF): δ ϭ 167.7
(COOH), 141.5, 135.3, 133.2, 131.2, 126.6, 123.6 (C6H3) ppm.
P(C6H5)3], Ϫ0.8 (SiMe3) ppm. 31P{1H} NMR (161.8 MHz, [D6]a-
cetone): δ ϭ 29.4 [P(C6H5)3] ppm.
[Ni(PCy3)(siS3)] (4): A solution of PCy3 (200 mg, 0.71 mmol) in
THF (2 mL) was added dropwise to a solution of 1 (300 mg,
0.22 mmol) in THF (10 mL). Over the course of ca. 5 min, the
color of the solution changed from dark brown to dark yellow. The
solution was stirred for 3 h, filtered, reduced in volume to ca. 2 mL,
and layered with MeOH (20 mL). Yellow-red microcrystals precip-
itated, which were separated after 3 d, washed with MeOH
(10 mL), and dried in vacuo. Yield: 452 mg (93%). C36H57NiPS3Si2
(731.889): calcd. C 59.08, H 7.85, S 13.14; found C 59.32, H 7.96,
1
S 12.69. MS (FD, THF): m/z ϭ 731 [Mϩ]. H NMR (399.7 MHz,
CDCl3): δ ϭ 7.74 (d, 2 H, C6H3), 7.28 (d, 2 H, C6H3), 6.98 (t, 2
H, C6H3), 2.10Ϫ1.28 (m, 33 H, PCy3), 0.37 (s, 18 H, SiMe3) ppm.
13C{1H} NMR (100.4 MHz, CDCl3): δ ϭ 159.0 (d, 3JPC ϭ 10 Hz),
[Ni(siS3)]3 (1): siS3-H2 (3.00 g, 7.60 mmol) in THF (40 mL) was ad-
ded dropwise to a solution of Ni(ac)2·4H2O (1.90 g, 7.65 mmol) in
MeOH (25 mL). A dark brown solution formed which was stirred
for 24 h and then concentrated to dryness. The resulting dark
brown residue was redissolved in hexane (20 mL), traces of insol-
uble particles were removed by filtration after 30 min, and the fil-
trate was layered with MeOH (50 mL). A dark brown powder pre-
cipitated, which was separated, washed with MeOH (30 mL) and
pentane (25 mL), and dried in vacuo. Yield: 3.02 g (87%).
C54H72Ni3S9Si6 (1354.36): calcd. C 47.89, H 5.36, S 21.31; found
4
141.2, 135.0, 133.1 (d, JPC ϭ 1.6 Hz), 128.7, 122.0 (C6H3), 34.5
(d, 1JPC ϭ 20.1 Hz), 30.7, 28.5 (d, 3JPC ϭ 11 Hz), 27.1 [P(C6H11)3],
0.0 (SiMe3) ppm. 31P{1H} NMR (161.8 MHz, CDCl3): δ ϭ 31.9
[P(C6H11)3] ppm.
Bu4N[Ni(Cl)(siS3)] (5): Bu4NCl (210 mg, 0.76 mmol) was added to
a dark brown solution of 1 (312 mg, 0.23 mmol) in THF (10 mL).
The solution was stirred for 12 h, over the course of which its color
changed to violet. The solution was filtered, reduced in volume to
2 mL, and layered with Et2O (20 mL). Pink crystals precipitated
which were separated after 7 d, washed with Et2O (15 mL), and
dried in vacuo. Yield: 410 mg (81%). C34H60ClNNiS3Si2 (729.377):
calcd. C 55.99, H 8.29, N 1.92, S 13.19; found C 56.01, H 8.32, N
C 47.58, H 5.53, S 20.98. MS (FD, THF): m/z ϭ 1354 [Mϩ], 902
ϩ
[Ni(siS3)]2
.
1H NMR (399.7 MHz, [D8]THF): δ ϭ 7.82 (d, 1 H,
C6H3), 7.68 (d, 1 H, C6H3), 7.40 (d, 1 H, C6H3), 7.28 (t, 1 H, C6H3),
7.24 (d, 1 H, C6H3), 6.96 (t, 1 H, C6H3), 0.55 (s, 9 H, SiMe3), 0.08
(s, 9 H, SiMe3) ppm. 13C{1H} NMR (100.4 MHz, [D8]THF): δ ϭ
158.8, 146.7, 145.1, 139.3, 138.5, 135.4, 134.8, 132.2, 130.9, 127.8,
127.6, 122.1 (C6H3), 0.6, Ϫ0.6 (SiMe3) ppm.
1
2.07, S 12.72. H NMR (269.7 MHz, [D8]THF): δ ϭ 7.60 (d, 2 H,
C6H3), 7.18 (d, 2 H, C6H3), 6.79 (t, 2 H, C6H3), 3.57 (m, 8 H,
NCH2), 1.76 (m, 8 H, NCH2CH2), 1.39 [m, 8 H, N(CH2)2CH2],
0.87 [m, 12 H, N(CH2)3CH3], 0.36 (s, 18 H, SiMe3) ppm. 13C{1H}
NMR (67.8 MHz, [D8]THF): δ ϭ 161.6, 139.6, 134.7, 134.6, 128.9,
120.7 (C6H3), 59.7, 35.1, 20.7, 14.2 [N(CH2)3CH3], Ϫ0.2 (SiMe3)
ppm.
[Ni(PnPr3)(siS3)] (2): PnPr3 (0.16 mL, 0.99 mmol) was added to a
solution of 1 (400 mg, 0.30 mmol) in THF (15 mL). The solution
instantaneously changed its color from dark brown to dark yellow,
was filtered after 1 h, reduced in volume to 2 mL, and layered with
pentane (20 mL). Orange microcrystals precipitated which were
separated after 5 d, washed with pentane (10 mL), and dried in
vacuo. Yield: 435 mg (80%). C27H45NiPS3Si2 (611.694): calcd. C
53.02, H 7.42, S 15.73; found C 53.28, H 7.24, S 15.47. MS (FD,
Bu4N[Ni(StBu)(siS3)] (6): Whilst stirring, NaStBu (1 mL of 1 
MeOH solution, 1.00 mmol) was added to a solution of 1 (300 mg,
0.22 mmol) in THF (10 mL). After 1 h, Bu4NOH (0.68 mL, 1 
MeOH solution, 0.68 mmol) was added and the stirring continued
for another 2 h. A dark brown solution resulted, which was filtered,
concentrated in volume to 2 mL, and layered with pentane (15 mL).
Dark brown microcrystals precipitated which were separated after
5 d, washed with pentane (5 mL) and dried in vacuo. Yield: 340 mg
(65%). C38H69NNiS4Si2 (783.106): calcd. C 58.28, H 8.88, N 1.79,
S 16.37; found C 58.43, H 8.97, N 1.91, S 15.89. 1H NMR
(269.7 MHz, CDCl3): δ ϭ 7.52 (d, 2 H, C6H3), 7.14 (d, 2 H, C6H3),
6.78 (t, 2 H, C6H3), 3.32 (m, 8 H, NCH2), 1.59 (m, 8 H,
NCH2CH2), 1.53 (s, 9 H, StBu), 1.31 [m, 8 H, N(CH2)2CH2], 0.88
[m, 12 H, N(CH2)3CH3], 0.34 (s, 18 H, SiMe3) ppm. 13C{1H} NMR
(67.8 MHz, CDCl3): δ ϭ 161.6, 139.5, 133.7, 133.0, 127.9, 119.7
(C6H3), 58.9 (NCH2), 40.4, 36.8 (StBu), 24.2, 19.7 13.9
[N(CH2)3CH3], Ϫ0.5 (SiMe3) ppm.
1
THF): m/z ϭ 611 [Mϩ]. H NMR (269.7 MHz, CDCl3): δ ϭ 7.64
(d, 2 H, C6H3), 7.24 (d, 2 H, C6H3), 6.94 (t, 2 H, C6H3), 1.74 (m,
6 H, PCH2), 1.06 (m, 6 H, PCH2CH2), 0.37 (s, 18 H, SiMe3), 0.05
(t, 9 H, PCH2CH2CH3) ppm. 13C{1H} NMR (100.4 MHz, CDCl3):
3
δ ϭ 159.0 (d, JP,C ϭ 13.2 Hz), 141.1, 135.1, 133.6, 129.1, 122.3
1
3
(C6H3), 26.7 (d, JP,C ϭ 26.40 Hz), 18.7, 16.7 (d, JP,C ϭ 14.1 Hz)
(PCH2CH2CH3), 0.0 (SiMe3) ppm. 31P{1H} NMR (161.8 MHz,
CDCl3): δ ϭ 14.6 [Pn(C3H7)3] ppm.
[Ni(PPh3)(siS3)] (3): Whilst stirring, a solution of PPh3 (200 mg,
0.76 mmol) and 1 (280 mg, 0.21 mmol) in THF (10 mL) was heated
to reflux for 5 min, in the course of which the color changed from
dark brown to red. The red solution was stirred for another 30 min
at room temperature, then combined with MeOH (30 mL), filtered,
and reduced in volume to ca. 5 mL. Red microcrystals precipitated
Et4N[Ni(N3)(siS3)] (7): A solution of Et4NCl (95 mg, 0.57 mmol)
which were separated after 3 d, washed with MeOH (10 mL), and and 1 (250 mg, 0.19 mmol) in THF (10 mL) was stirred for 3 h,
dried in vacuo. Yield: 268 mg (76%). C36H39NiPS3Si2 (713.72):
calcd. C 60.58, H 5.51, S 13.48; found C 60.48, H 5.80, S 13.51.
over the course of which the color changed from dark brown to
purple. Me3SiN3 (0.1 mL, 0.76 mmol) was added, whereupon the
color became slightly lighter. After 1 h, all volatile materials were
1
MS (FD, THF): m/z ϭ 712 [Mϩ]. H NMR (269.7 MHz, [D6]ace-
Eur. J. Inorg. Chem. 2002, 2138Ϫ2146
2143

D. Sellmann, R. Prakash, F. Geipel, F. W. Heinemann
FULL PAPER
removed in vacuo, the residue was redissolved in THF (10 mL).
The THF solution was filtered, reduced in volume to 2 mL and
layered with pentane (15 mL). Violet needles precipitated, which
NMR spectra of the solutions indicated the complete conversion
of 1 into 9. 1H NMR (269.7 MHz, [D8]THF): δ ϭ 7.63 (d, 2 H,
C6H3), 7.23 (d, 2 H, C6H3), 6.89 (t, 2 H, C6H3), 2.27 (b, 3 H, NH3),
were separated after 4 d, washed with pentane (10 mL), and dried 0.37 (s, 18 H, SiMe3) ppm. 13C{1H} NMR (67.8 MHz, [D8]THF):
in vacuo. Yield: 285 mg (82%). C26H44N4NiS3Si2 (623.729): calcd.
C 50.07, H 7.11, N 8.98, S 15.42; found C 50.61, H 7.40, N 8.70,
S 15.19 Ϫ IR (KBr): ν˜ ϭ 2037 [ν(N3)] cmϪ1. 1H NMR (269.7 MHz,
CDCl3): δ ϭ 7.48 (d, 2 H, C6H3), 7.26 (d, 2 H, C6H3), 6.90 (t, 2
H, C6H3), 3.40 (m, 8 H, NCH2), 1.20 (t, 12 H, NCH2CH3), 0.37
(s, 18 H, SiMe3) ppm. 13C{1H} NMR (67.8 MHz, CDCl3): δ ϭ
157.9, 140.0, 134.5, 132.9, 127.8, 120.9 (C6H3), 52.6, 7.8
[N(CH2CH3)4], Ϫ0.9 (SiMe3) ppm.
δ ϭ 158.4, 140.6, 135.3, 134.5, 129.6, 122.0 (C6H3), Ϫ0.5 (SiMe3)
ppm.
[Ni(L)(siS3)] Complexes (L ؍ NA or NAEt2): In a typical experi-
ment, NA (0.5 g, 4.09 mmol) or NAEt2 (1.0 mL, 5.95 mmol) was
added to a dark brown solution of 1 (500 mg, 0.37 mmol) in THF
(10 mL). The solution was stirred for 48 h, over the course of which
its color changed to yellow red. The solution was filtered, reduced
in volume to 2 mL, and layered with Et2O (20 mL). Yellow red
powders precipitated which were separated after 5 d, washed with
Et2O (15 mL), and dried in vacuo. Elemental analyses and IR and
NMR spectra indicated that these powders were mixtures of
[Ni(L)(siS3)] and 1, which could not be separated.
[Ni(N2H4)(siS3)] (8): Addition of N2H4 (2 mL of 1  THF solution,
2.00 mmol) to a solution of 1 (250 mg, 0.19 mmol) in THF (10 mL)
led to a rapid color change from dark brown to orange. The solu-
tion was stirred for 2 h and stored at Ϫ30 °C for 12 h. At this
temperature, the excess free hydrazine that crystallized from the
solution could be removed by filtration at Ϫ30 °C. The filtrate was
reduced in volume to 2 mL and layered with pentane (20 mL).
Dark red crystals precipitated which were separated, washed with
pentane (10 mL) and dried in vacuo. Yield: 242 mg (90%).
C18H28N2NiS3Si2 (489.499): calcd. C 44.71, H 5.84, N 5.79, S
19.90; found C 45.01, H 5.88, N 5.51, S 19.43. IR (KBr): ν˜ ϭ 3350
[ν(NH)] cmϪ1. 1H NMR (269.7 MHz, [D8]THF): δ ϭ 7.62 (d, 2 H,
C6H3), 7.25 (d, 2 H, C6H3), 6.90 (t, 2 H, C6H3), 4.83 (b, 2 H,
NH2NH2), 3.32 (b, 2 H, NH2), 0.39 (s, 18 H, SiMe3) ppm. 13C{1H}
NMR (67.8 MHz, [D8]THF): δ ϭ 157.6, 140.9, 135.5, 134.5, 129.9,
122.4 (C6H3), Ϫ0.4 (SiMe3) ppm.
1H NMR Spectroscopic Monitoring of the Reactions between 1 and
NA or NAEt2: To a dark brown solution of 1 (25 mg, 0.02 mmol)
in [D8]THF, NA, or NAEt2 (1Ϫ10 equiv.) was added stepwise, and
the 1H NMR spectra were recorded after every addition. The
SiMe3 signals were used as a spectroscopic probe to monitor the
formation of the corresponding [Ni(L)(siS3)] complex.
X-ray
Structure
Determination
of
[Ni(siS3)]3·0.5CD2Cl2
(1·2THF·3MeOH),
(1·0.5CD2Cl2),
[Ni(siS3)]3·2THF·3MeOH
[Ni(PPh3)(siS3)]
(3),
[Ni(PCy3)(siS3)]·2CDCl3
(4·2CDCl3),
Bu4N[Ni(Cl)(siS3)]·0.625THF·0.375Et2O (5·0.625THF·0.375Et2O),
Et4N[Ni(N3)(siS3)]·THF (7·THF): In an NMR tube at Ϫ30 °C,
black blocks of [Ni(siS3)]3·0.5CD2Cl2 (1·0.5CD2Cl2) crystallized in
[Ni(NH3)(siS3)] (9): This compound was synthesized in an NMR
tube and characterized only by 1H and 13C NMR spectra: NH3 gas the course of 10 d from a CD2Cl2 solution of 1 which had been
(2.5 mL, 0.15 mmol) was injected into the dark brown solution of
layered with MeOH. From THF/MeOH mixtures, 1 crystallized as
1·2THF·3MeOH. The crystallographic data of this solvate have
been deposited. Red cubes of 3 and orange-prisms of 4·2CDCl3
1 (25 mg, 0.02 mmol) in [D8]THF contained in an NMR tube. The
1
color of the solution immediately changed to red. The H and 13C
Table 3. Selected crystallographic data for [Ni(siS3)]3·0.5CD2Cl2 (1·0.5CD2Cl2), [Ni(PPh3)(siS3)] (3), [Ni(PCy3)(siS3)]·2CDCl3 (4·2CDCl3),
Bu4N[Ni(Cl)(siS3)]·0.625THF·0.375Et2O (5·0.625THF·0.375Et2O), and Et4N[Ni(N3)(siS3)]·THF (7·THF)
1·0.5CD2Cl2
3
4·2CDCl3
5·0.625THF·0.375Et2O 7·THF
Empirical formula
Formula mass [g/mol]
Crystal system
Space group
a [pm]
b [pm]
c [pm]
C54.50H72ClDNi3S9Si6 C36H39NiPS3Si2 C38H57Cl6D2NiPS3Si2 C38H68.75ClNNiOS3Si2 C30H52N4NiOS3Si2
1397.79
monoclinic
C2/c
3232.3(3)
2452.3(3)
1996.6(2)
90
713.71
monoclinic
Cc
2664.0(8)
1883.1(6)
1518.2(5)
90
972.61
orthorhombic
P212121
1236.2(1)
1720.6(2)
2266.2(2)
90
802.21
monoclinic
P21/c
1343.8(2)
3057.9(4)
2237.9(3)
90
695.83
orthorhombic
Pbca
1951.2(2)
1572.2(2)
2404.8(4)
90
α [°]
β [°]
118.88(1)
90
13.858(3)
8
105.10(3)
90
7.353(4)
8
90
90
4.8202(8)
4
95.16(1)
90
9.159(2)
8
90
90
7.377(2)
8
γ [°]
V [nm3]
Z
dcalcd.[g/cm3]
1.340
1.253
1.289
0.831
1.337
0.974
1.164
0.698
1.253
0.789
µ [mmϪ1
]
Crystal size [mm]
2θ range[°]
0.80ϫ0.70ϫ0.35
3.6Ϫ54.0
0.358/0.419
16730
0.55ϫ0.30ϫ0.10 0.64ϫ0.60ϫ0.42
0.90ϫ0.80ϫ0.20
3.6Ϫ50.0
0.278/0.341
19091
0.96ϫ0.48ϫ0.36
3.7Ϫ54.0
0.261/0.340
9574
3.5Ϫ54.0
0.984/1.000
16914
3.6Ϫ56.0
0.224/0.269
12783
Tmin/Tmax
Measd. refl.
Indep. refl.
15146
8679
11611
16114
8046
Obsd. refl.
10965
882
4.39; 10.57
2691
787
5.09; 8.63
8889
467
5.52; 13.88
6482
881
8.64; 21.32
4403
380
6.60; 16.67
Ref. parameters
R1[a]
; wR2[%]
Abs. struct. parameters
0.01(2)
0.00(2)
[a]
[I Ͼ 2σ(I)].
2144
Eur. J. Inorg. Chem. 2002, 2138Ϫ2146

Highly Soluble Sulfur-Rich [Ni(L)(siS3)] Complexes
FULL PAPER
[5] [5a]
H. J. Krüger, R. H. Holm, Inorg. Chem. 1989, 28,
were grown at Ϫ20 °C over the course of 3Ϫ5 d from a concen-
trated THF solution which was layered with MeOH. Red-violet
plates of 5·0.625THF·0.375Et2O formed over the course of 7 d
when a saturated THF solution of 5 was layered with Et2O at Ϫ30
°C. Red-black crystals of 7·THF were obtained from a dilute THF/
acetone mixture of 7 which was layered with pentane and stored for
8 d at Ϫ30 °C. Suitable single crystals were embedded in protective
perfluoro polyether or were sealed in glass capillaries under N2.
1148Ϫ1155. [5b] M. Kumar, G. J. Colpas, R. O. Day, M. J. Ma-
[5c]
roney, J. Am. Chem. Soc. 1989, 111, 8323Ϫ8325.
M. Frey,
[5d]
Struct. Bond 1998, 97Ϫ126.
H. Wang, C. Y. Raltson, D. S.
Patil, R. M. Jones, W. M. Verhagen, M. Adams, P. C. Riordan,
C. A. Marganian, P. Mascharak, J. Kovacs, C. C. Miller, T. J.
Collins, S. Brooker, P. D. Croucher, K. Wang, E. I. Steifel, S.
P. Cramer, J. Am. Chem. Soc. 2000, 122, 10544Ϫ10552.
[6] [6a]
S. Fox, Y. Wang, A. Silver, M. Millar, J. Am. Chem. Soc.
1990, 112, 3218Ϫ3220. [6b] H. J. Krüger, G. Peng, R. H. Holm,
Data
were
collected
at
200 K
(1·0.5CD2Cl2,
[6c]
Inorg. Chem. 1991, 30, 734Ϫ742.
P. Stavropoulos, M. C.
5·0.625THF·0.375Et2O, 7·THF), 220 K (4·2CDCl3) or 293 K (3)
with a Siemens P4 diffractometer or a Nicolet R 3m/V diffracto-
meter (3) using Mo-Kα radiation (λ ϭ 71.073 pm), a graphite mon-
ochromator, and the ω-scan technique. For all compounds a semi-
empirical absorption correction using ψ-scans has been performed.
The structures were solved by direct methods, full-matrix least-
squares refinement was carried out on F2 (SHELXTL NT 5.1).[21]
All non-hydrogen atoms were refined anisotropically. The hydrogen
atoms of 1·0.5CD2Cl2 were located from a difference Fourier map,
while in all other compounds the H atoms were geometrically posi-
tioned with isotropic displacement parameters being 1.5 times
U(eq) of the preceding carbon atom. One n-butyl group in the cat-
ion of 5·0.625THF·0.375Et2O was found to be disordered. Two al-
ternative sites could be refined with occupancy factors of 57(2) and
43(2)%, respectively. One THF and one Et2O molecule of the in-
cluded solvent share a single site. These disordered molecules have
been refined using several restraints. Selected crystallographic data
are summarized in Table 3.[22]
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2145

D. Sellmann, R. Prakash, F. Geipel, F. W. Heinemann
FULL PAPER
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CCDC-170684 (1·0.5CD2Cl2), -170685 (1·2THF·3MeOH),
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-170686
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Handbook of Chemistry
(5·0.625THF·0.375Et2O), and -170689 (7·THF) contain the
supplementary crystallographic data for this paper. These data
can be obtained free of charge at www.ccdc.cam.ac.uk/conts/
retrieving.html or from the Cambridge Crystallographic Data
Centre, 12 Union Road, Cambridge CB2 1EZ, UK [Fax: (in-
ternat.) ϩ 44-1223/336-033; E-mail: deposit@ccdc.cam.ac.uk].
Received December 12, 2001
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