Oxidation of spirocyclohexyl-1,2,4-trithiolane and complexation reaction with [Pt(η2-nb)(PPh3)2]

Article abstract of DOI:10.1002/ejic.200700890

Oxidation of spirocylcohexyl-1,2,4-trithiolane 1 yielded the 4-S- and 1-S-oxide, 2 and 3, respectively. The complexation reactions of 1-3 with [Pt(η²-nb)(PPh₃)₂] (4; nb = norbornene) have been studied. The formed dithiolato, thioketone, thiolatosulfenato and sulfine complexes 5-8 have been isolated and characterized by ¹H-, ³¹P NMR and IR spectroscopy and by mass spectrometry. The mechanism of the reaction is discussed. The reaction proceeds by insertion of the Pt ⁰ complex fragment into the sulfur-sulfur bond and subsequent ring contraction by extrusion of a thioketone or sulfine. Comparison of the molecular structures of the oxidized complexes 7 and 8 with the nonoxidized complex 5 shows elongation of the sulfenato-platinum bond and elongation of the platinum-phosphorus bond in the corresponding trans position. The product formed suggests that, in this system, formation of thiolato-platinum bonds is energetically favoured to sulfenato-platinum bonds. The structures of 5, 7 and 8 were established by X-ray crystallography. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.

Full text of DOI:10.1002/ejic.200700890

FULL PAPER
DOI: 10.1002/ejic.200700890
Oxidation of Spirocyclohexyl-1,2,4-trithiolane and Complexation Reaction with
[Pt(η2-nb)(PPh3)2]
Holm Petzold,[a] Silvio Bräutigam,[a] Helmar Görls,[a] Wolfgang Weigand,*[a]
Jaroslaw Romanski,[b] and Grzegorz Mloston*[b]
Keywords: Insertion reactions / 1,2,4-Trithiolanes / Platinum / S ligands / Thioketone complexes
Oxidation of spirocylcohexyl-1,2,4-trithiolane 1 yielded the
4-S- and 1-S-oxide, 2 and 3, respectively. The complexation
reactions of 1–3 with [Pt(η2-nb)(PPh3)2] (4; nb = norbornene)
have been studied. The formed dithiolato, thioketone, thiola-
tosulfenato and sulfine complexes 5–8 have been isolated
son of the molecular structures of the oxidized complexes 7
and 8 with the nonoxidized complex 5 shows elongation of
the sulfenato–platinum bond and elongation of the platinum–
phosphorus bond in the corresponding trans position. The
product formed suggests that, in this system, formation of thi-
olato–platinum bonds is energetically favoured to sulfenato–
platinum bonds. The structures of 5, 7 and 8 were established
by X-ray crystallography.
1
and characterized by H-, 31P NMR and IR spectroscopy and
by mass spectrometry. The mechanism of the reaction is dis-
cussed. The reaction proceeds by insertion of the Pt0 complex
fragment into the sulfur–sulfur bond and subsequent ring
contraction by extrusion of a thioketone or sulfine. Compari-
(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
Germany, 2007)
3,3,5,5-tetramethyl-1,2,4-trithiolane were oxidized, and the
diverse oxides were obtained and characterized. The study
showed that the oxidation reactions with m-chloroperben-
zoic acid (m-CPBA) result in the formation of a mixture of
1-S- and 4-S-oxides in comparable amounts.[8] Over the last
years, reactions of cyclic disulfanes, thiosulfinates and
thiosulfonates with Pt0 have been described, which result in
dithiolato, sulfenato thiolato, sulfinato thiolato, as well as
thiosulfonato PtII complexes. Except for the latter com-
pound, all the compounds were formed by oxidative ad-
dition of Pt0 complexes to the S–S(O)n moiety (n = 0–
2).[9–13] 1,2,4-Trithiolanes and their 1-S-oxides undergo re-
actions with Pt0 complexes.[9,13]
Introduction
1,2,4-Trithiolanes form a class of sulfur-rich five-mem-
bered heterocycles, which have attracted considerable atten-
tion in recent times. The parent compound as well as some
3,5-dialkyl-1,2,4-trithiolanes are naturally occurring sub-
stances.[1] On the other hand, 3,3,5,5-tetrasubstituted deriv-
atives are easily formed as interception products of the reac-
tion of intermediate thiocarbonyl S-sulfides (thiosulfines)
with dipolarophilic thioketones.[2]
It is well known that the heating of these heterocycles in
solution or in the gas phase (Flash Vacuum Pyrolysis, FVP)
results in a cycloreversion reaction leading to thiosulfines
(existing in an equilibrium with isomeric dithiiranes) and
the corresponding thioketones.[3,4] In this way, 1,2,4-trithi-
olanes are used as a convenient source of in situ formed
thiosulfines, which subsequently can be trapped by other
dipolarophiles.[4] Very recently 1,2,4-trithiolanes have been
used for syntheses of mimics for the active site of [Fe-only]-
hydrogenase.[5,6] Along with the parent 1,2,4-trithiolane,
there are also some oxidized species found in marine organ-
isms.[7] In a recent investigation, the parent as well as the
Here we present a systematic investigation of the reactiv-
ity of the 1,2,4-trithiolane 1 and of its 4-S- and 1-S-oxide,
2 and 3, respectively, with [Pt(η2-nb)(PPh3)2] (4; nb = nor-
bornene).
Results and Discussion
The spirocyclohexyl-1,2,4-trithiolane 1 was oxidized by
using m-CPBA. After separation by means of column
chromatography, two main products were obtained as pure
compounds (Scheme 1), along with some starting material
and a mixture of two higher oxides.[14] The 13C NMR spec-
trum of the first eluted fraction shows 12 different signals.
The signals at δ = 95.5 and 82.3 ppm are assigned to the
quaternary C atoms C3 and C5. The second eluted fraction
shows only six different signals, and for C3 and C5, only
one signal at δ = 84.6 ppm is found. The elemental analysis
and the found molecular peak in the mass spectra confirm
[a] Institut für Anorganische und Analytische Chemie, Friedrich-
Schiller Universität Jena,
August-Bebel Str. 2, 07743 Jena, Germany
Fax: +49-3641-948102
E-mail: c8wewo@uni-jena.de
[b] Section of Heteroorganic Compounds, University of Łódz´,
Narutowicza 68, 90-136 Łódz´, Poland
Fax: +48-42-6781609
E-mail: gmloston@uni.lodz.pl
Supporting information for this article is available on the
WWW under http://www.eurjic.org or from the author.
Eur. J. Inorg. Chem. 2007, 5627–5632
© 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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H. Petzold, S. Bräutigam, H. Görls, W. Weigand, J. Romanski, G. Mloston
FULL PAPER
the formula C12H20S3O; hence, the minor product is the 1-
S-oxide 3 and the major product must be the 4-S-oxide 2.
The amount of the isolated 4-S-oxide 2 is nearly four times
that of the 1-S-oxide 3. Both products are crystalline; they
are therefore more manageable than the tetramethyl deriva-
tives.[8] The tendency to form the 4-S-oxide over the 1-S-
oxide is well known for the unsubstituted 1,2,4-trithiolane
and 3,3,5,5-tetramethyl-1,2,4-trithiolane.[7,8] In contrast, for
the more bulkily substituted derivatives, such as tetra-
phenyl[13] and 3,5-di-tert-butyl-3,5-diphenyl derivatives,[15]
exclusive oxidation at S1 and S2 is observed.
Figure 1. ORTEP[26] drawing of the molecular structure of the di-
thiolato complex 5 (for clarity, hydrogen atoms are omitted and the
phenyl groups are represented only by their ipso-carbon atoms).
Selected bond lengths (Å) and angles (°): Pt–P2 2.2874(7); Pt–P1
2.2820(6); Pt–S1 2.3123(7); Pt–S2 2.3231(7); S1–C1 1.847(3); S2–
C1 1.836(3); P2–Pt–P1 99.89(2); S1–Pt–S2 75.54(2).
and a second complex 7 (Scheme 3). The pure complex 7
was isolated in 52% yield with respect to 2 equiv. 4 in a
manner similar to that described for the dithiolato complex
5. The 31P NMR spectrum of 7 shows an AB spin system
with a 2J(P,P) value of 16 Hz and 1J(P,Pt) values of 3324 Hz
and 2343 Hz. Elemental analysis and mass spectroscopy
confirm the molecular formula of C42H40OP2PtS2. In the
Scheme 1. Oxidation of spirocyclohexyl-1,2,4-trithiolane 1.
Treatment of spirocyclohexyl-1,2,4-trithiolane 1 with
2 equiv. [Pt(η2-nb)(PPh3)2] (4) in toluene at 50 °C yielded a
1:1 mixture of two complexes (Scheme 2) in the crude prod-
uct according to the 31P NMR spectrum. This spectrum
showed the existence of two spin systems, one A2 spin sys-
tem with a 1J(P,Pt) value of 2971 Hz and an AB spin system
with a 2J(P,P) value of 16 Hz and 1J(P,Pt) values of 4600 Hz
and 2838 Hz. The first spin system is typical for complexes
of the type [Pt(PPh3)2(S2CR2)] and is assigned to the dithi-
olato complex 5; fractional crystallization gave the pure
complex 5 in 64% yield with respect to 2 equiv. 4. The re-
sults of the X-ray analysis are shown in Figure 1. The com-
plex has a distorted quadratic planar geometry with a small
S–Pt–S angle of 75.54(2) °. The S–Pt bond lengths of
2.3123(7) and 2.3231(7) Å are slightly longer than the P–Pt
bond lengths of 2.2874(7) and 2.2820(6) Å. The structure is
comparable to those reported for the similar com-
plexes.[10,16]
IR spectrum, a strong broad band is found at ν = 995 cm–1,
˜
which is typical for sulfenato ligands bound to platinum-
(II).[11d,13] Finally, X-ray analysis unambiguously confirms
the expected structure of the sulfenato thiolato complex 7.
The molecular structure of 7 is shown in Figure 2.
Scheme 3. Reaction of spirocyclohexyl-1,2,4-trithiolane 4-S oxide 2
with 4.
The complex has a distorted sqare–planar geometry. The
sulfur–platinum bond length (S1–Pt) is 2.3174(6) Å and is
in the range of those found in the dithiolato complex 5. A
similar bond length relative to that in 5 is observed for the
phosphorus–platinum bond P2–Pt [2.2944(6) Å] in the trans
position. In contrast, the sulfur–platinum bond S2–Pt to
the sulfenato ligand is slightly elongated by 0.01 Å. The
higher trans influence of the sulfenato ligand results in an
Scheme 2. Reaction of 1,2,4-trithiolane 1 with platinum complex 4.
The second spin system observed in the 31P NMR spec- elongation the P1–Pt bond by approximately 0.04 Å. This
trum is assigned to the thioketone complex 6. An indepen- observation is in a good agreement with the smaller value
dent synthesis from cyclohexanonethione and [Pt(η2- observed for the 1J(P,Pt) constant. The sulfur–oxygen bond
nb)(PPh3)2] yielded a sample whose identity was confirmed in the sulfenato ligand [1.503(2) Å] is slightly longer than
to be 6 by TLC and 31P NMR spectroscopy. The fragmen- those reported for similar sterically crowded complexes.[12]
tation of 1 found is similar to that reported for the reaction
Complex 4 reacted with the 1-S oxide 3 at room tempera-
ture in a few minutes to yield a 1:1 mixture of the dithiolato
of bulkily substituted 1,2,4-trithiolanes with Fe2(CO)9.[5]
Similar treatment of the 4-S-oxide 2 with excess [Pt(η2- complex 5 and a new product 8, which shows an AB spin
nb)(PPh3)2] gave a 1:1 mixture of the thioketone complex 6 system with a J(P,P) value of 24 Hz and J(P,Pt) values of
2
1
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© 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Inorg. Chem. 2007, 5627–5632

Oxidation of Spirocyclohexyl-1,2,4-trithiolane and Complexation with Pt
Figure 2. ORTEP[26] drawing of the molecular structure of the sul-
Figure 3. ORTEP[26] drawing of the molecular structure of the sulf-
fenato thiolato complex 7 (for clarity, hydrogen atoms are omitted
and the phenyl groups are represented only by their ipso-carbon
atoms). Selected bond lengths (Å) and angles (°): Pt–P2 2.2944(6);
Pt–P1 2.3193(6); Pt–S1 2.3174(6); Pt–S2 2.3336(6); S1–C1 1.837(2);
S2–C1 1.858(2); S2–O 1.503(2); P2–Pt–P1 100.01(2); S1–Pt–S2
74.33(2).
ine complex 8 [for clarity, hydrogen atoms and O1A are omitted
and the phenyl groups are represented only by their ipso-carbon
atoms]. Selected bond lengths (Å) and angles (°): Pt–P2 2.3038(16);
Pt–P1 2.2867(16); Pt–S1 2.3338(18); Pt–C1 2.126(6); S1–C1
1.770(6); S1–O1 1.436(8); S1–O1A 1.321(13); P2–Pt–P1 105.29(6);
S1–Pt–C1 46.48(17).
3817 Hz and 3075 Hz in the 31P NMR spectrum
(Scheme 4). In the mass spectrum, the molecular peak is
found at m/z = 850, and the elemental analysis confirms the
molecular formula C42H40OP2PtS. On the basis of these
data, structure 8 can be assigned to the isolated complex.
The result is in good agreement with that observed in the
reaction between 3,3,5,5-tetraphenyl-1,2,4-trithiolane 1-S-
oxide and [Pt(η2-C2H4)(PPh3)2].[13] Recrystallization from a
thf/pentane mixture yielded crystals that were suitable for
X-ray analysis. The results are shown in Figure 3.
fur–sulfur bond of the 1,2,4-trithiolane ring.[9,11b,13] Ring
contraction of the six-membered platinacycles formed, by
expulsion of a thioketone or sulfine, leads to the four-mem-
bered platinacycles 5 and 7, respectively. The former thio-
ether sulfur atom is bonded to the platinum atom. In the
last step, the thioketone or sulfine is complexed by a second
equivalent of 4 to yield 6 or 8, respectively. The exclusive
formation of 5 and 8 in the reaction of the 1-S-oxide 3
with 4 suggests the favoured formation of thiolato ligands
instead of sulfenato ligands in this system.
Conclusions
In summary, the reactions of spirocylcohexyl-1,2,4-trithiol-
ane 1 and of its 4-S- and 1-S-oxide, 2 and 3, respectively,
proceed by insertion of the Pt0 complex fragment into the
sulfur–sulfur bond and subsequent ring contraction by ex-
pulsion of a thioketone or sulfine. The reactions yield the
thioketone complex 6 and dithiolato complex 5, as well as
their mono S-oxides 8 and 7. Comparison of the molecular
structures of the oxidized and nonoxidized complexes
shows an elongation of the sulfenato–platinum bond as well
as the elongation of the platinum–phosphorus bond in the
corresponding trans position. Selective extrusion of a sulf-
ine instead of the thioketone in the case of 3 suggests that
the formation of thiolato–platinum bonds is energetically
favoured over sulfenato–platinum bonds.
Scheme 4. Reaction of spirocyclohexyl-1,2,4-trithiolane 1-S oxide 3
with 4.
The sulfine fragment incorporated in complex 8 is coor-
dinated by an η2 mode and the complex has a distorted
square-planar coordination sphere. The structure is com-
parable with that reported for the 9H-fluorene-9-thione-S-
oxide complex.[17] The P1–Pt bond located in the trans posi-
tion to the oxidized sulfur atom has
a length of
2.2867(16) Å and the value for this bond length falls at the
higher end of the range (2.25–2.30 Å) found for thioketone
complexes.[9,10,18,19] In contrast to that found in the struc-
ture of 6, the sulfur–platinum bond in 8 is remarkably
longer [2.3338(18) Å] than those found in thioketone com-
plexes (2.27–2.29 Å).[9,10,18,19] In the registered spectra of
the crude product, there is no indication for the formation
of 6 or 7.
Experimental Section
General: Melting points were determined with an AXIOLAB
microscope with a TMHS 600 heating plate and are uncorrected.
1H-, 31P- and 13C NMR spectra were determined with BRUKER
DRX 400 or BRUKER DRX 200 spectrometers at 30 °C; chemical
shifts are referred to the protons of the solvent or 85% H3PO4.
31P- and 13C NMR spectra are proton decoupled. IR spectra were
Taking this into account, the reactions of 1,2,4-trithiol-
ane 1 and of the oxides 2 and 3 likely proceed in the first
step by insertion of the Pt0 complex fragment into the sul- recorded with a PERKIN ELMER System 2000 FT-IR spectrome-
Eur. J. Inorg. Chem. 2007, 5627–5632
© 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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H. Petzold, S. Bräutigam, H. Görls, W. Weigand, J. Romanski, G. Mloston
FULL PAPER
1
ter. Mass spectra were recorded with a FINNIGAN MAT SSQ
710 mass spectrometer. Elemental analyses were determined with a
LECO CHNS-932. All reactions were performed under argon, and
solvents were dried by using sodium/benzophenone. Starting mate-
rials 7,14,15-trithia-dispiro[5.1.5.2]pentadecane (1)[20] and the Pt0
complex 4[18] were prepared according to the literature procedures.
NMR (81 MHz, CDCl3): δ = 21.0 (d, 2JP,P = 16, JP,Pt = 3324 Hz),
2
1
19.8 (d, JP,P = 16, JP,Pt = 2343 Hz) ppm. IR (KBr): ν = 3054,
˜
2927, 2852, 1969 (w), 1818 (w), 1632 (s br.), 1481, 1435 (s), 1185,
1096 (s), 1019, 998, 995 (br.)/955 (br.) (S=O), 744 (s), 693 (s), 539/
523/513/497 (PC3) cm–1. MS (FAB): m/z (%) = 882 (4), 767 (24)
[M
–
(S=C(CH2)5)]+, 718 (20) [(Ph3P)2Pt]+. C42H40OP2PtS2
(881.92): calcd. C 57.20, H 4.57, S 7.27; found C 56.71, H 4.61, S
7.02.
Oxidation of Spirocyclohexyl-1,2,4-trithiolane 1: m-CPBA (70%,
1.2 g, 5.4 mmol) dissolved in CH2Cl2 (10 mL) was added in small
portions to a solution of spirocyclohexyl-1,2,4-trithiolane 1 (1 g,
3.8 mmol) in CH2Cl2 (20 mL) at 0 °C. The reaction mixture was
stirred for an additional 2 h and subsequently washed with a di-
luted aqueous solution of NaHCO3. The organic layer was sepa-
rated, dried with Na2SO4, and reduced to dryness, and the residue
was subjected to column chromatography to yield the 1-S-oxide 3
and the 4-S-oxide 2, as well as a mixture of higher oxides.
Reaction of Spirocyclohexyl-1,2,4-trithiolane 1-S-Oxide
3 with
[Pt(η2-nb)(PPh3)2] (4): A portion of spirocyclohexyl 1,2,4-trithiol-
ane 1-S-oxide 3 (25 mg, 0.09 mmol) was added to a solution of 4
(120 mg, 0.15 mmol) in toluene (10 mL) at room temperature. The
colour of the reaction mixture became slightly yellow, and after
some minutes, a solid precipitated. The formation of the dithiolato
complex 5 and the sulfine complex 8 was confirmed by TLC. The
solvent was evaporated, and residue was subjected to column
chromatography (THF/hexane, 1:2, SiO2). The first substantial
fraction was assigned to the dithiolato complex 5, and second frac-
tion contained the sulfine complex 8; this fraction was collected to
yield the pure sulfine complex 8. White crystals. Yield: 25 mg
(40%). M. p. 193 °C dec. 1H NMR (200 MHz, CDCl3): δ = 7.33
(m, 6 H), 7.24 (m, 12 H), 7.15 (m, 12 H), 2.43 (d, JH,H = 13 Hz),
1.57 (m, 1 H), 1.49 (m, 3 H), 1.41 (m, 2 H), 1.09 (m, 1 H), 1.05
(m, 1 H), 0.84 (m, 1 H) ppm. 13C NMR (100 MHz, CD2Cl2): δ =
134.2 (m, ipso-C), 134.0 (m, Ph-C), 129.8 (s, Ph-C), 128.4 (s, Ph-
C), 127.8 (m, Ph-C), 83.4 [d, 2J(C,P) = 53 Hz], 33.0 (s br.), 32.4 (d,
JC,P = 6 Hz), 29.1 (d, JC,P = 8 Hz), 28.7, 26.6 ppm. 31P{1H} NMR
Spirocyclohexyl-1,2,4-trithiolane 1-S-Oxide 3: Colourless crystals.
1
Yield: 70 mg (6.6%). M.p. 46 °C. H NMR (200 MHz, CDCl3): δ
= 2.25–2.1 (m, 4 H), 2.1–1.9 (m, 4 H), 1.8–1.3 (m, 12 H) ppm. 13C
NMR (50 MHz, CDCl3): δ = 95.5 (q-C), 82.3 (q-C), 49.5, 43.6,
36.8, 32.4, 26.8, 26.1, 25.6, 25.0, 24.2, 23 ppm. IR (KBr): ν = 2920
˜
(s), 1447 (s), 1098 [s, (S=O)] cm–1. C12H20OS3 (277.49): calcd. C
52.13, H 7.29, S 34.79; found C 52.15, H 6.59, S 35.01.
Spirocyclohexyl-1,2,4-trithiolane 4-S-Oxide 2: Colourless crystals.
1
Yield: 240 mg (23%). M.p. 115 °C. H NMR (200 MHz, CDCl3):
δ = 2.09 (m), 1.90 (dt), 1.78 (m), 1.63 (m), 1.33 (m) ppm. 13C NMR
(50 MHz, CDCl3): δ = 84.6 (q-C), 33.7, 28.2, 25.2, 24.6, 23.1 ppm.
IR (KBr): ν = 2931 (s), 1443 (s), 1067 [s, (S=O)] cm–1. C H OS
˜
12 20
3
2
1
(81 MHz, CDCl3): δ = 27.4 (d, JP,P = 24, JP,Pt = 3817 Hz), 26.4
(277.49): calcd. C 52.13, H 7.29, S 34.79; found C 52.06, H 7.21, S
34.92.
Reaction of Spirocyclohexyl 1,2,4-Trithiolane 1 with [Pt(η2-nb)-
2
1
(d, JP,P = 24, JP,Pt = 3075 Hz) ppm. IR (KBr): ν = 3072, 3053,
˜
2923, 2847, 1968 (w), 1900 (w), 1816 (w), 1634 (s br.), 1480, 1434
(s), 1183, 1095 (s), 1027, 1011, 997, 983 (S=O), 743 (s), 695 (s), 538/
521/510/497 (PC3) cm–1. MS (FAB): m/z (%) = 850 (15), 719 (100)
[(Ph3P)2Pt]+. C42H40OP2PtS (849.86): calcd. C 59.36, H 4.74, S
3.77; found C 59.23, H 4.86, S 3.43.
(PPh3)2] (4):
A portion of spirocyclohexyl-1,2,4-trithiolane 1
(30 mg, 0.11 mmol) was added to a solution of 4 (120 mg,
0.15 mmol) in toluene (10 mL). The solution immediately turned
red and was stirred for an additional 3 h at 50 °C. The formation
of the dithiolato complex 5 and the thioketone complex 6 in a 1:1
ratio was monitored by TLC. The solvent was reduced to dryness,
and the crude product was washed with diethyl ether. The residue
was dissolved in thf (10 mL) and filtered through silica gel. The
solvent was reduced (to 5 mL), and the mixture was stored in a
flask with pentane (10 mL). After 1 d, the dithiolato complex 5 was
obtained. Yellow crystals. Yield: 40 mg (64%). M.p. 275 °C dec. 1H
NMR (400 MHz, CD2Cl2): δ = 7.44 (m, 12 H), 7.30 (m, 6 H), 7.20
(m, 12 H), 1.86 (m, 4 H), 1.44 (m, 4 H), 1.25 (m, 2 H) ppm. 13C
NMR (100 MHz, CD2Cl2): δ = 135.0 (t, JC,P = 5.5 Hz), 131.0 (m),
130.5, 127.9 (t, JC,P = 5.2 Hz), 68.1 (s, 2JC,Pt = 58 Hz), 50.5 (s, 3JC,Pt
Synthesis of the Cyclohexanethione Complex 6: Cyclohexanon di-
ethyl ketal (1 g, 5.8 mmol) was dissolved in nonane (30 mL). A
stream of hydrogen sulfide was passed through the reaction mix-
ture, and a few drops of concentrated sulfuric acid were added. The
mixture became red. After 30 min, the excess hydrogen sulfide was
removed by passing a stream of argon through. Solid NaHCO3 was
added, and the organic layer was washed with water and dried with
Na2SO4. The nonane was distilled off under reduced pressure, and
cyclohexanthione was trapped in a cooling trap as a solution in
nonane. Complex 4 (80 mg, 0.1 mmol) in toluene (10 mL) was
added to this solution. The solvent was evaporated, and the residue
was washed with diethyl ether, dissolved in thf (15 mL) and filtered
over silica gel. The solvent was reduced (to 3 mL), and the mixture
was stored in a flask with pentane (20 mL). After some days, pure
thioketone complex 6 crystallized. White crystals. Yield: 50 mg
= 23 Hz), 25.9, 23.3 ppm. 31P{1H} NMR (81 MHz, CDCl3): δ =
1
24.76 (s, JP,Pt = 2971 Hz) ppm. IR (KBr): ν = 3073, 3052, 2925,
˜
2850, 1967 (w), 1903 (w), 1820 (w), 1628 (s br.), 1480, 1434 (s),
1185, 1095 (s), 1028, 1014, 998, 743 (s), 693 (s), 542/525/515/497
(PC3) cm–1. MS (FAB): m/z (%) = 865 (0.5) [M]+, 752 (1) [M –
(S=C(CH2)5)]+, 718 [(Ph3P)2Pt]+, 307 (100). C42H40P2PtS2 (865.92):
calcd. C 58.26, H 4.66, S 7.41; found C 58.26, H 4.74, S 7.19.
1
(60%). M.p. 234 °C dec. H NMR (400 MHz, CDCl3): δ = 7.39–
7.30 (m, 12 H), 7.24–7.11 (m, 18 H); 1.6–1.4 (m, 9 H), 0.87 (m, 1
H) ppm. 13C NMR (100 MHz, CDCl3): δ = 135.4–133.4 (m), 133.8
2
(m), 129.2 (m), 127.3 (m), 86.3 (d, JC,P = 55 Hz), 43.8, 33.1 (d,
Reaction of Spirocyclohexyl 1,2,4-trithiolane 4-S-Oxide 2 with
[Pt(η2-nb)(PPh3)2] (4): The reaction was carried out in a manner
similar to that with the unoxidized spirocyclohexyl 1,2,4-trithiolane
1, except with spirocyclohexyl-1,2,4-trithiolane 4-S-oxide 2 (31 mg,
0.11 mmol). TLC as well as 31P NMR spectroscopy of the crude
product showed the formation of a 1:1 mixture of 6 and 7. In anal-
ogy to 5 the sulfenato thiolato complex 7 was isolated by
chromatography and subsequent crystallization. Yellow crystals.
Yield: 35 mg (52%). M.p. 222 °C dec. 1H NMR (200 MHz,
2
3JC,P = 8.5, JC,Pt = 45 Hz), 27.4 ppm. 31P{1H} NMR (81 MHz,
2
1
2
CDCl3): δ = 28.2 (d, JP,P = 16, JP,Pt = 4600 Hz), 27.0 (d, JP,P
=
1
16, JP,Pt = 2838 Hz) ppm. IR (KBr): ν = 3052, 2921, 2844, 1964
˜
(w), 1626 (br.), 1479, 1434 (s), 1183, 1094 (s), 1027, 1014, 998, 742,
695 (s), 542/521/511/497 (PC3) cm–1. MS (FAB): m/z (%) = 719 (1)
[M – (S=C(CH2)5)]+. C42H40P2PtS (833.86): calcd. C 60.49, H 4.83,
S 3.85; found C 60.19, H 4.82, S 3.67.
Crystal Structure Determination: The intensity data for the com-
CDCl3): δ = 7.50–7.18 (m, 30 H), 1.98–1.3 (m, 10 H) ppm. 31P{1H} pounds were collected on a Nonius KappaCCD diffractometer by
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Eur. J. Inorg. Chem. 2007, 5627–5632

Oxidation of Spirocyclohexyl-1,2,4-trithiolane and Complexation with Pt
using graphite-monochromated Mo-Kα radiation. Data were cor-
rected for Lorentz and polarization effects and for absorption ef-
fects.[21–23] The structures were solved by direct methods
(SHELXS[24]) and refined by full-matrix least-squares techniques
[1]
a) G. S. Nielsen, L. M. Larsen, L. Poll, J. Agric. Food Chem.
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2
against Fo (SHELXL-97[25]). All hydrogen atoms of the structures
were included at calculated positions with fixed thermal param-
eters. With the exception of the carbon atom C1 in compound 8,
all non-disordered, non-hydrogen atoms were refined anisotropi-
cally.[25] The oxygen atom in complex 8 had a 50:50 occupancy
disorder over two positions, we therefore will not discuss the S–O
bond length for the compound. Ortep-3 for Windows[26] was used
for the structure representations.
[2] a) K. Okuma, Sulfur Rep. 2002, 23, 209–241; b) G. Mloston,
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and Properties (Eds.: O. A. Attanasi; D. Spinelli) , Italian Soci-
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Chem. 2001, 113, 401–404; Angew. Chem. Int. Ed. 2001, 40,
393–396.
Crystal Data for 5: C42H40P2PtS2, Mr = 865.89 gmol–1, colourless
prism, size 0.02ϫ0.02ϫ0.02 mm, triclinic, space group P1, a =
¯
10.4720(2), b = 11.4799(3), c = 16.6495(3) Å, α = 75.337(1), β =
[4]
a) R. Huisgen, J. Rapp, Tetrahedron 1997, 53, 939–960; b) G.
Maier, H. P. Reisenauer, J. Romanski, H. Petzold, G. Mloston,
Eur. J. Org. Chem. 2006, 3721–3729.
73.691(1), γ = 82.905(1)°, V = 1855.49(7) Å3, T = –90 °C, Z = 2,
ρcalcd. = 1.550 gcm–3, µ(Mo-Kα) = 40.09 cm–1, multiscan, transmin
:
[5] J. Windhager, H. Görls, H. Petzold, G. Mloston, G. Linti, W.
Weigand, Eur. J. Inorg. Chem. 2007, 4462–4471.
[6] a) L. C. Song, Z. Y. Yang, Y. J. Hua, H. T. Wang, Y. Liu, Q.-
M. Hu, Organometallics 2007, 26, 2106–2110; b) J. Windhager,
M. Rudolph, S. Braeutigam, H. Goerls, W. Weigand, Eur. J.
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[8] H. Petzold, S. Bräutigam, H. Görls, W. Weigand, U. Uhlem-
ann, R. Geßner, W. Kiefer, J. Popp, A. Majchrzak, G. Mloston,
Inorg. Chim. Acta 2004, 357, 1897–1908.
[9] a) W. Weigand, R. Wünsch, C. Robl, G. Mloston, H. Nöth,
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G. Mloston, Chem. Eur. J. 2006, 12, 8090–8095.
0.5208, transmax: 0.6615, F(000) = 864, 13452 reflections in h(–13/
13), k(–14/14), l(–21/20), measured in the range 2.11°ՅΘՅ27.31°,
completeness Θmax = 98.9%, 8262 independent reflections, Rint
0.0189, 7656 reflections with Fo Ͼ 4σ(Fo), 424 parameters, 0 re-
straints, R1obs = 0.0233, wR2obs = 0.0560, R1all = 0.0269, wR2all
=
=
0.0579, GOOF = 1.015, largest difference peak and hole: 0.968/–
1.061 eÅ–3.
Crystal Data for 7: C42H40OP2PtS2, Mr = 881.89 gmol–1, colourless
¯
prism, size 0.02ϫ0.02ϫ0.01 mm, triclinic, space group P1, a =
10.5086(2), b = 11.3733(2), c = 16.6699(4) Å, α = 76.040(1), β =
74.247(1), γ = 83.006(1)°, V = 1857.50(7) Å3, T = –90 °C, Z = 2,
ρcalcd. = 1.577 gcm–3, µ (Mo-Kα) = 40.08 cm–1, multiscan, transmin
:
[11] a) T. Shigetomi, H. Soejima, Y. Nibu, K. Shioji, K. Okuma, Y.
Yokomori, Chem. Eur. J. 2006, 12, 7742–7748; b) W. Weigand,
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175; c) A. Ishii, M. Murata, H. Oshida, K. Matsumoto, J.
Nakayama, Eur. J. Inorg. Chem. 2003, 3716–3721; d) W. Wei-
gand, R. Wünsch, Chem. Ber. 1996, 129, 1409–1419; e) A. Ishii,
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[12] A. Ishii, M. Saito, M. Murata, J. Nakayama, Eur. J. Org. Chem.
2002, 979–982.
0.6680, transmax: 0.7621, F(000) = 880, 13298 reflections in h(–13/
13), k(–14/14), l(–21/20), measured in the range 2.02°ՅΘՅ27.46°,
completeness Θmax = 99.4%, 8451 independent reflections, Rint
0.0184, 8026 reflections with Fo Ͼ 4σ(Fo), 433 parameters, 0 re-
straints, R1obs = 0.0223, wR2obs = 0.0545, R1all = 0.0244, wR2all
=
=
0.0556, GOOF = 1.023, largest difference peak and hole: 0.939/–
1.383 eÅ–3.
Crystal Data for 8: C42H40OP2PtS, Mr = 849.83 gmol–1, colourless
prism, size 0.05ϫ0.05ϫ0.05 mm, orthorhombic, space group
Pbca, a = 16.0302(3), b = 16.2448(4), c = 27.5941(6) Å, V =
7185.7(3) Å3, T = –90 °C, Z = 8, ρcalcd. = 1.571 gcm–3, µ (Mo-Kα)
= 40.85 cm–1, multiscan, transmin: 0.4608, transmax: 0.5615, F(000)
= 3392, 43387 reflections in h(–20/17), k(–17/21), l(–33/35), mea-
sured in the range 2.61°ՅΘՅ27.54°, completeness Θmax = 99.2%,
8219 independent reflections, Rint = 0.1025, 4772 reflections with
Fo Ͼ 4σ(Fo), 429 parameters, 0 restraints, R1obs = 0.0528, wR2obs
= 0.0948, R1all = 0.1191, wR2all = 0.1134, GOOF = 0.987, largest
difference peak and hole: 2.072/–3.542 eÅ–3.
[13] W. Weigand, R. Wünsch, K. Polborn, G. Mloston´, Z. Anorg.
Allg. Chem. 2001, 627, 1518–1522.
[14] The 13C NMR spectrum of this isolated fraction shows two
different sets of 12 signals for each compound. The signals for
the quaternary ring carbon atoms appear at 103.5/93.1 and
91.4/86.7 ppm. Attempts to separate the two compounds were
in vain.
[15]
a) H. Oshida, A. Ishii, J. Nakayama, J. Org. Chem. 2004, 69,
1695–1703; b) H. Oshida, A. Ishii, J. Nakayama, Tetrahedron
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a) A. Shaver, R. D. Lai, P. H. Bird, W. Wickramasinghe, Can.
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Trans. 1999, 639–651.
CCDC-655294 (5), -655295 (7), and -655296 (8) contain the
supplementary crystallographic data for this paper. These data can
be obtained free of charge from The Cambridge Crystallographic
Data Centre via www.ccdc.cam.ac.uk/data_request/cif.
[17]
J. W. Gosselink, G. van Koten, K. Vrieze, B. Zwanenburg,
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419.
Supporting Information (see footnote on the first page of this arti-
cle): The IR spectra of complexes 5–8 are included.
[18]
[19]
[20]
[21]
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H. Petzold, H. Görls, W. Weigand, J. Organomet. Chem. 2007,
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H. Petzold, H. Görls, W. Weigand, J. Romanski, G. Mloston,
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1959, 627, 195–201.
COLLECT, Data Collection Software; Nonius B. V., Nether-
lands, 1998.
Z. Otwinowski, W. Minor, “Processing of X-ray Diffraction
Data Collected in Oscillation Mode” in Methods in Enzy-
Acknowledgments
Financial support for this work was provided by the Freistaat
Thüringen and DAAD (PKZ D/04/11451, H. P.). G. M. and J. R.
acknowledge financial support by the Rector of the University of
Łódz´ (Grant No. 505/712).
Eur. J. Inorg. Chem. 2007, 5627–5632
© 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
5631

H. Petzold, S. Bräutigam, H. Görls, W. Weigand, J. Romanski, G. Mloston
mology, Vol. 276, Macromolecular Crystallography, Part A [25] G. M. Sheldrick, SHELXL-97 (Release 97–2), University of
FULL PAPER
(Ed.: C. W. Carter, R. M. Sweet), Academic Press 1997, pp.
Göttingen, Germany, 1997.
[26] Ortep-3 for Windows: L. J. Farrugia, J. Appl. Crystallogr. 1997,
30, 565.
307–326.
[23] SORTAV: R. H. Blessing, Acta Crystallogr., Sect. A 1995, 51,
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Received: August 28, 2007
[24] G. M. Sheldrick, Acta Crystallogr., Sect. A 1990, 46, 467–473.
Published Online: November 13, 2007
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Eur. J. Inorg. Chem. 2007, 5627–5632