Metallacycles of 1,4-bis(3-thiophenyl)-1,3-butadiyne in mixed metal clusters derived by C-C bond coupling of alkynyls

Article abstract of DOI:10.1021/om050748w

Reaction of cw-Pt(C≡CTp)₂(dppe) (Tp = thiophene) with Ru₃(CO)₁₁(CH₃CN) in refluxing toluene for 1 h resulted in head-to-head C-C bond coupling of the alkynyl ligands forming 1,4-bis(3-thiophenyl)-buta-1,3-diyne, which afforded an extraordinal 1,4-heterodimetalla[5,6-b]thienopentalene, [PtRu₃{μ ₄η¹:η¹:η¹: η¹:η⁴:η⁴C₄H ₂S-C=CC(H)=CTp}(μ-CO)₂(CO)₆(dppe)] (1) (Tp = 3-thiophene), in 54% yield. Its crystal structure shows that a hydrogen shift occurs from the thiophene substituent to an end carbon atom of the 1,3-diyne, transforming 1,4-bis(3-thiophenyl)buta-1,3-diene, which results in formations of PtC₄ and RuC₄ rings, both with metallacyclopenta-2,4- diene. The Ru₃(μ-CO)₂(CO)₆ moiety conforms to an open cluster, and its central ruthenium atom forms a RuCp ring whose carbon atoms bond to two ruthenium atoms by eight Ru-C π-bonds. Reactions of the acetylides with single metal media, Fe(CO)₅, gave rise to annealation of alkynyls via both cyclic and acyclic dimerization processes, affording extraordinal metallacycles of 1,3-diyne, a platinacyclobutene consisting of a cyclone, [FePt{μ₂η¹: η¹:η⁴ (C₄Tp₂-CO)-CO}(CO) ₃(dppe)] (2), and a 1,2-heterodimetallacyclo-3-penten-5-one, [FePt(μ₂-η¹:η¹:η ²TpCCCCTp-CO)(μ-CO)(CO)₂](dppe)] (3), in 15 and 16% yields, respectively.

Full text of DOI:10.1021/om050748w

Organometallics 2006, 25, 849-853
849
Metallacycles of 1,4-Bis(3-thiophenyl)-1,3-butadiyne in Mixed Metal
Clusters Derived by C-C Bond Coupling of Alkynyls
Shinsaku Yamazaki,*,† Zenei Taira,‡ Toshiaki Yonemura,§ and Anthony J. Deeming
Chemistry Laboratory, Kochi Gakuen College, 292 Asahi Tenjin-cho, Kochi 780-0955, Japan, Department
of Pharmaceutical Sciences, Tokushima Bunri UniVersity, 180 Boji, Nishihama, Ymashiro-cho, Tokushima
770-8055, Japan, Department of Material Sciences, Faculty of Sciences, Kochi UniVersity,
2-1-5 Akebono-cho, Kochi 780-8520, Japan, and Christopher Ingold Laboratory, Department of Chemistry,
UniVersity College London, 20 Gordon Street, London WC1H OAJ, U.K.
ReceiVed August 31, 2005
Reaction of cis-Pt(CtCTp)2(dppe) (Tp ) thiophene) with Ru3(CO)11(CH3CN) in refluxing toluene
for 1 h resulted in head-to-head C-C bond coupling of the alkynyl ligands forming 1,4-bis(3-thiophenyl)-
buta-1,3-diyne, which afforded an extraordinal 1,4-heterodimetalla[5,6-b]thienopentalene, [PtRu3{µ4-
η1:η1:η1:η1:η4:η4-C4H2S-CdCC(H)dCTp}(µ-CO)2(CO)6(dppe)] (1) (Tp ) 3-thiophene), in 54% yield.
Its crystal structure shows that a hydrogen shift occurs from the thiophene substituent to an end carbon
atom of the 1,3-diyne, transforming 1,4-bis(3-thiophenyl)buta-1,3-diene, which results in formations of
PtC4 and RuC4 rings, both with metallacyclopenta-2,4-diene. The Ru3(µ-CO)2(CO)6 moiety conforms to
an open cluster, and its central ruthenium atom forms a RuCp ring whose carbon atoms bond to two
ruthenium atoms by eight Ru-C π-bonds. Reactions of the acetylides with single metal media, Fe(CO)5,
gave rise to annealation of alkynyls via both cyclic and acyclic dimerization processes, affording
extraordinal metallacycles of 1,3-diyne, a platinacyclobutene consisting of a cyclone, [FePt{µ2-η1:η1:η4-
(C4Tp2-CO)-CO}(CO)3(dppe)] (2), and a 1,2-heterodimetallacyclo-3-penten-5-one, [FePt(µ2-η1:η1:η2-
TpCCCCTp-CO)(µ-CO)(CO)2](dppe)] (3), in 15 and 16% yields, respectively.
pally through the C-C bond coupling of alkynyls have been
recently applied toward use as a single-source precursor of
chemical vapor deposition of ceramic thin films.4
Introduction
A number of metallacyclic compounds have recently been
investigated as important intermediates of metal-catalyzed
oligomerization of alkynes1 and syntheses of hetero- and
carbocyclic organic molecules.2 In these studies, five-membered
metallacycles that undergo complexation have intriguing bond-
ing features,3 whose bond multiplicity has been proposed as an
intermediate of bond scission of C-C single bond of the 1,3-
diyne.2e,13,14 Mixed dimetallic compounds thus derived princi-
Four-membered metallacycles (A in Figure 1), the first [(η5-
C5H5)Co{(R1CdCR2)CdNR3}(PPh3)] (R1 ) Ph, R2 ) CO2-
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* To whom correspondence should be addressed. Tel: 81-088-840-1121.
Fax: 81-088-840-1123. E-mail: yamazaki@kochi-gc.ac.jp.
† Kochi Gakuen College.
‡ Tokushima Bunri University.
§ Kochi University.
An Emeritus Professor, University College London.
(1) Farona, M. F.; Thanedar, S.; Famili, A. J. Polym. Sci. 1986, 24,
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10.1021/om050748w CCC: $33.50 © 2006 American Chemical Society
Publication on Web 01/14/2006

850 Organometallics, Vol. 25, No. 4, 2006
Yamazaki et al.
Figure 2.
Scheme 1
We have extended the syntheses of the five-membered
metallacycles by using acetylides with thiophene substituents.
Reactions of cis-Pt(CtCTp)2(dppe) (Tp ) 3-thiophene) with
metal-carbonyls, Ru3(CO)11(CH3CN) and Fe(CO)5, were per-
formed in refluxing toluene for 45 min, which led to the isola-
tion of an extraordinal dimetallapentalene G, [PtRu3{µ4-
η1:η1:η1:η1:η4:η4-C4H2S-CCC(H)CTp}(µCO)2(CO)6(dppe)] (1),
and metallacyclobutene H, consisting of condensed ring A with
a cyclone ring, [FePt{µ4-η1:η1:η4-(C4Tp2-CO)-CO}(CO)3(dppe)]
(2), both of which underwent complexation. Despite the many
recent studies on π-pentalene complexes,6 metallapentalene is
elusive, except for iridapentalene F,7 in which the metal occupies
a bridge-head position (Figure 1).
Figure 1.
Me; R3 ) p-MeC6H4),5a [(η5C5H5)Rh{κ(C,C)-C(dNMe)-
CPhdCPh}(SbiPr3)],5b and [(η5C5H5)Co(PPh3){η1:η1CHCO2-
Et(SiMe3)CdC(SO2Ph)}],5c were all isolated in incoporation
processes of isocyanide, SbiPr3, and diazoacetate into the
corresponding π-alkyne complexes, respectively.
Five-membered MC4 metallacycles of alkyne and 1,3-diyne
molecules are intriguing in their structures and bondings,8 since
small cyclic alkynes are unstable owing to ring strain.9 1-Met-
allacyclopenta-2,3,4-triene C and 1-metallacyclo-3-pentyne D
recently isolated in electron-poor transition metal compounds
of titanocene and zirconocene10-12 are all planar. On electron-
rich transition metals, another intriguing five-membered met-
allacycle of dicarbene structure has been known. Cp*RuCl(d
C(Ph)-CHd)2 E has recently been isolated from reaction of
Cp*RuCl(COD) with a 2-fold amount of phenylacetylene, which
further reacts with phenylacetylene to afford a cationic cyclo-
trimerized product.15e However, on clusters of electron-rich
transition metals, there are only a few reports of five-membered
metallcycles of 1,3-diyne.15a
We have recently established a new type of dimetallacycles
of 1,3-diyne unusually interacting with cluster nuclei, which
have been prepared by cross-coupling of alkynyls induced by
metal-carbonyl,16 as shown in I and J in Figure 2. I is a cluster
with isomers in which all atoms of the RuC4 ring of the
ruthenacyclopentadiene12 undergo complexation to three metals
by a (δ:η1:η1:η4)-bond. The stable cluster J is another extra-
ordinal type of five-membered metallacycle with 1-metallacy-
clocumulene, whose structure includes a hybrid resonance of
metallacyclo-3-pentyne (J-A).
Results and Discussion
A head-to-head cross-coupling of alkynyls in cis-Pt(CCTp)2-
(dppe) (Tp ) 3-thiophene) was induced by Ru3(CO)11(CH3-
CN) and proceeded to afford a mixed metal compound of 1,3-
diyne, [PtRu3(C2C4H3S)2(CO)8(dppe)] (1) (Tp ) 3-thiophene),
in 54% yield (Scheme 1). The crystal structure of 1, in Figure
3, shows that a hydrogen shift occurs from a ring carbon atom
of the substituted thiophene to an end carbon atom of 1,3-diyne,
resulting in the formation of 1,4-heterodimetalla[5,6-b]thieno-
pentalene (Scheme 1), consisting of RuC4 and PtC4 rings both
with metallacyclopentadiene. Four carbon atoms in the RuCp
ring bond to two ruthenium atoms by eight Ru-C π-bonds
{bond lengths Ru1-C3 2.303(8) Å, Ru1-C 42.303(9) Å, Ru1-
C1 Ru2-C3 2.333(8) Å, Ru1-C2 2.328(9) Å, Ru2-C1 2.342-
(9) Å, Ru2-C3 2.292(9) Å, Ru2-C2 2.313(9), and Ru2-C4
2.317(8) Å: mean bond length 2.316 Å} in opposite directions,
and the Ru3(µ-CO)2(CO)6 group conforms to an open cluster
{atomic distance Ru1-Ru2 3.7515(11) Å and bond angle Ru1-
Ru3-Ru2 88.71(3)°}. Bond lengths Ru3-C3 2.212(8) Å and
Ru3-C4 2.202(9) Å in the RuCp ring are comparable with
2.216(4)-2.219(4) Å found for the alkyne-dimerized com-
pounds [Ru3(C4Ph4)(CO)8]17a and [Ru3(CH3CCiPr)2(CO)8]17c and
the alkyne-trimerized product [Ru3(HCCtBu)3(CO)8].17b In the
present case, the C-C double-bond lengths, C1-C3 1.446(11)
and C2-C4 1.458(13) Å, are elongated from those of metal-
lacyclopentadiene, and they are longer than the bond length C1-
(15) (a) Sappa, E.; Lanfredi, A. M. M.; Tiripicchio, A. Inorg. Chim. Acta
1980, 42, 255. (b) Rosenberg, E.; Aime S.; Milone, L.; Sappa, E.;
Tiripicchio, A.; Lanfredi, A. M. M. J. Chem. Soc., Dalton Trans. 1981,
2023. (c) Bruce, M. I.; Zaitzeva, N. N.; Skelton, B. W.; White, A. H. J.
Organomet. Chem. 1997, 536. (d) Low, P. J.; Enright, G. D.; Carty, A. J.
J. Organomet. Chem. 1998, 565, 279-282. (e) Ernst, C.; Walter, O.; Dinjus,
E.; Arzberger, S.; Go¨rls, H. J. Prakt. Chem. 1999, 341, 801.
(16) (a) Yamazaki, S.; Taira, Z.; Yonemura, T.; Deeming, A. J.; Nakao,
A. Chem. Lett. 2002, 1174. (b) Yamazaki, S.; Taira, Z.; Yonemura, T.;
Deeming, A. J. Organometallics 2005, 24, 20.
(17) (a) Capparelli, M. V.; Sanctis, Y. De.; Arce, A. J. Acta Crystallogr.
1995, C51, 1819. (b) Sappa, E.; Lanfredi, A. M. M.; Tiripicchio, A. Inorg.
Chim. Acta 1980, 42, 255. (c) Rosenberg, E.; Aime, S.; Milone, L.; Sappa,
E.; Tiripicchio, A.; Lanfredi, A. M. M. J. Chem. Soc., Dalton Trans. 1981,
2023.

Metallacycles of 1,4-Bis(3-thiophenyl)-1,3-butadiyne
Organometallics, Vol. 25, No. 4, 2006 851
Figure 3. ORTEP plot (50% probability thermal ellipsoids) of [PtRu3(TpCCC(H)CC4H2S)2(dppe)(µ-CO)2(CO)6], 1. Phenyl rings of dppe
are omitted for clarity. Selected bond distances (Å) and angles (deg): PT(1)-C(1) 2.078(8), C3-C151 1.483(11), Pt1-C154 2.054(9),
C151-C154 1.396(13), PT(1)-C(154) 2.054(10), Ru1-C3 2.303(8) Ru1-Ru3 2.6865(12), Ru1-C4 2.303(9), Ru(2)-Ru(3) 2.687(2),
Ru1-C1 2.333(8), C1-C2 1.438(11), Ru1-C2 2.328(9), C1-C3 1.466(11), Ru2-C1 2.342(9), C2-C4 1.458(13), Ru2-C2 2.313(9),
Ru3-C3 2.212(8), Ru2-C3 2.292(9), Ru3-C4 2.202(9), Ru2-C4 2.317(8), Ru(2)-C(9) 1.891(13), Ru1-Ru3-Ru2 88.71(3), C1-Pt1-
C154 78.2(3), Ru3-C3-C1 119.3(5), Pt1-C154-C151 118.6(6), Ru3-C4-C2 117.9(6), C3-C151-C154 114.8(7), C2-C1-C3 112.7-
(7), C1-C3-C151 111.3(7), C1-C2-C4 116.3(8), Pt1-C1-C3 117.0(5), C3-Ru3-C4 73.8(3), Ru3-C4-C2 117.9(6).
Scheme 2
C2 1.438(11) Å, owing to the eight Ru-C π-bonds, whose
length is rather similar to those of metallacyclopentyne. The
PtC4 ring in the present compound is retained as a 1-metalla-
cyclobuta-2,4-diene, and bond lengths Pt1-C1 2.078(8) and
Pt1-C154 2.054(9) Å are consistent with a pure Pt-C σ-bond,
while the bond length C151-C154 1.396(13) Å in the PtC4
ring is shortened from the corresponding bond length C1-C3
1.466(11) Å in the RuC4 ring, but it is in the range of carbon-
carbon double-bond lengths. Three rings of thiophene, the
platinacycle, and the ruthenacycle are in good planarity and
almost in coplanarity {torsion angles are C1-C3-C141-C144
2.8(11)°, C3-C141-C144-Pt -2.7(11)°, C141-C142-C143-
S1 8(11)°, C144-C141-C142-C143-6(12)°; C3-C141-
C142-C143 176.1(9)°, Ru3-C3-C141-C142 5.7(15)°, Pt-
C1-C2-C4 178.1(16)°}. The hydrogen at the C2 atom was
fixed in the X-ray analysis.
Reactions of the acetylides with single metal media, Fe(CO)5,
in refluxing touene resulted in both cyclic and acyclic dimer-
izations through an analogous cross-coupling of alkynyls and
succeeding C-C bond coupling of the 1,3-diyne with carbon
monoxide from Fe(CO)5. These annealation reactions of 1,3-
diyne afforded unusual platinacyclobutenes, the cyclone
[FePt{µ2-η1:η1:η4-(C4Tp2-CO)-CO}(CO)3(dppe)] (2) and the
1,2-heterodimetallacyclo-3-pentene-5-one [FePt(µ2-η1:η1:η2-
TpCCCCTp-CO)(µ-CO)(CO)2] (dppe)] (3), in 14 and 16%
yields, respectively, as shown in Scheme 2.
A single crystal of 2 was obtained from CH3CN-hexane at
253 K, and X-ray analyses were performed.18 It crystal structure
is shown in Figure 2. One carbon monoxide liberated from Fe-
(CO)5 now couples with an end carbon atom of the 1,3-diyne,
affording a π-cyclone compound,19 while another carbon
monoxide of the residual Fe(CO)4 group newly inserted into
the Pt-C bond, forming a metallacyclobutene ring.
The ring carbon atoms of the cyclone bond to the Fe(CO)3
group by the four Fe-C π-bonds, and the mean distance of the
(18) Crystal structure data of C42H29FeO5P2PtS2, 2: A single crystal was
obtained from a CH3CN-hexane solution; monoclinic, space group P21/n,
a ) 11.4350(3) Å, b ) 18.3300(7) Å, c ) 20.6730(10) Å, R ) 89.9980-
(20)°, â ) 82.6960(10)°, γ ) 90.00120(10)°, V ) 4298(2) Å3, Z ) 4, Dc
) 1.551 g‚cm-3, R1 ) 0.1060, wR2 ) 0.3447, Goof (S) ) 1.5810, for 9827
independent reflections, in the range 0° < 2θ < 51.54° with Fo > 4σ(Fo),
refining 7211 parameters. Selected bnond lengths (Å) and angles (deg):
C1-C2 1.491(19), C1-C3 1.46(2), C2-C4 1.38(2), C4-C10 1.55(2), C3-
C10 1.556(18), C11-O5 1.210(17), Pt1-C2 2.0752, C1-C11 1.48(2), Pt1-
C11 2.0739, Fe2-C1 2.041(15), Fe2-C2 2.135(14), Fe2-C3 2.137(16),
Fe2-C4 2.129(17), Fe2-C10 2.421(15), C2-Pt1-C11 67.97, C1-C2-
C4 105.6(13), C2-C1-C3 112.8(12), C1-C3-C10 103.5(12), C2-C4-
C10 110.9(14), C3-C10-C4 102.9(12), Pt1-C11-C1 94.80, Pt1-C2-
C1 94.31, C2-C1-C11 102.8(12), C2-Pt1-C11 67.97.
(19) (a) Best, W.; Fell, B.; Schmitt, G. Chem. Ber. 1976, 109, 2914. (b)
Yamazaki, S.; Taira, Z. J. Organomet. Chem. 1999, 578, 61.

852 Organometallics, Vol. 25, No. 4, 2006
Yamazaki et al.
Scheme 4
C4Tp2)(dppe)], as has been evidenced for the formation of an
analogue, [FePt{µ2-η1:η1:η2-C(O)C4Ph2}(CO)3(PPh3)2].16b In the
present case, the bond length Fe1-C1 2.052(10) Å is consider-
ably shorter than the bond length Fe1-C3 2.192(12) Å and
rather approaches 2.0151(24) and 2.021(3) Å of the Fe-C
σ-bond.20 The bond length C1-C3 1.381(17) Å corresponds to
a double-bond length8,16b and is much shorter than the corre-
sponding bond length of 1.441(14) Å in [FePt{µ2-η1:η1:η2-
C(O)C4Ph2}(CO)3(PPh3)2]. This may suggest that dimetallacy-
clopentenone 3 may still consist of resonance structures of a
bridging carbene with a ketene substiutuent and an allylic bond,
as shown in Scheme 4.
Figure 4. ORTEP plot (50% probability thermal ellipsoids) of
[PtFe{µ2-η1:η1:η4-(TpCCCCTp-CO)-CO}(CO)3(dppe)], 2. Phenyl
rings of dppe are omitted for clarity.
Scheme 3
It should be noted that 2 and 3 were obtained only when the
reactions were performed using an excess amount of Fe(CO)5,
while neither 2 nor 3 could be obtained when an equivalent
amount of Fe(CO)5 was used. This may indicate that the
dangling triple bond of an intermediate complex or compound
3 may interact with the iron-carbonyl.
Fe-C bond (2.11 Å) is slightly shorter than 2.21-2.24 Å of
the corresponding cyclone compound, [Ru(η4-C(O)R1C2R2 )-
2
Concluding Remarks
(CO)2(PPh3)] (R1 ) Ph, R2 ) CtCPh).19b A possible polarized
and charge-separated structure is depicted in Scheme 3.
The bond length C1-C2 1.47(3) Å of 2 is noticeably
elongated from those of the other two cobalta- and rhodacycles,
as shown in Figure 5, which may be due to an electron-
delocalized and polarized structure of the π-cyclone moiety.
The crystal structure of [FePt(µ2-η1:η1:η2-TpCCCCTp-CO)-
(µ-CO)(CO)2](dppe)] (3) is shown in Figure 6, in which an end
carbon atom of the 1,3-diyne undergoes C-C bond coupling
with one carbon monoxide from the Fe(CO)4 group, and the
other carbon atom of the bonding alkyne group links the
platinum atom by a pure Pt-C σ-bond {bond distance Pt-C1
2.090(12) Å}, forming a 1,2-dimetalla-3-penten-5-one com-
pound with a metal-metal bond (Pt1-Fe1) of 2.605(2) Å and
bridging carbonyl. 3 is evidently formed by incoporation of a
Fe(CO)4 group into a π-1,3-diyne in the 16 e- species [Pt(η2-
The present work is the first study of the preparation of the
unusual heterodimetallapentalene 1 and metallacyclobutene 2
condensed with a cyclone ring that underwent complexation. 1
is formed by the head-to-head cross-coupling of the acetylide.
A subsequent C-H bond activation of the thiophene ring
accompanied a conversion of the 1,3-diyne into 1,4-bis-
(thiophenyl)buta-1,3-diene, which newly forms the PtCp and
RuCp rings both with 1-metallacyclo-2,4-pentadiene. Cross-
coupling of the acetylides was also induced by single-metal
media, Fe(CO)5, and succeedingly C-C bond coupling of the
1,3-diyne with carbon monooxide from Fe(CO)5 also proceeded
to form 2 and 3. We have previously established that the acyclic
dimerizations of the acetylides with an aryl substituent proceeded
via a reductive elimination, first affording a 16-electron
species.16b Therefore, in the present case, compound 3 may
Figure 5. Bond lengths of the metallacyclobutene ring for CpCo{PhSO2CdC(SiMe3)C(dNCH3)}(PMe3) (A-1), [CpRh{PhCdCPh-C(d
NCH3)}(SbiPr3)] (A-2), and compound 2 (A-3).

Metallacycles of 1,4-Bis(3-thiophenyl)-1,3-butadiyne
Organometallics, Vol. 25, No. 4, 2006 853
give dark orange products, which were separated by TLC (SiO2)
using CH2Cl2. From the eluent of the main dark orange band in
CH2Cl2, followed by recrystallization from toluene and CH2Cl2,
red crystals were obtained (170 mg, 0.13 mmol: 54% yield/platinum
atom). Anal. Found: C, 40.58; H, 2.25. Calc for C46H30O8P2-
PtRu3S2‚1/2(CH2Cl2): C, 40.54; H, 2.27. IR (Nujol mull): ν˜ (cm-1),
2049s {ν(CO)}, 2009vs {ν(CO)}, 1974vs {ν(CO)}, 1956vs {ν-
(CO-Ru)}, 1854s {ν(CO)b}, 1838s {ν(CO)b}. 31P NMR (CDCl3):
δ (ppm) 49.4 (JPt,P ) 3855 Hz), 37.9 (JPt,P ) 3642 Hz). 13C NMR
(CDCl3): δ (ppm) 200.4 (Ru-CO), 199.5 (Ru-CO), 198.1, 196.9
(Ru-CO), 193.3 (Ru-CO), 166 (d, JP,C ) 8.3 Hz), 165.0, 151.2.
Preparation of [FePt{µ2-η1:η1:η4-(C4Tp2-CO)-CO}(CO)3-
(dppe)], 2. To Pt(CCC4H3S)2(dppe) (200 mg, 0.25 mmol) in toluene
was added Fe(CO)5 (0.18 g, 0.9 mmol), and the mixed solution
was refluxed for 45 min. The solution, after cooling, was evapo-
rated, and the products were purified by TLC (SiO2). An eluent of
the yellow band, followed by recrystallization from toluene, gave
orange crystals (37 mg, 0.037 mmol; 15% yield/platinum atom).
Anal. Found: C, 50.94; H, 3.14. Calc for C42H29FeO5P2PtS2: C,
51.46; H, 3.01. IR (CH2Cl2): ν˜ (cm-1), 2016vs, 1955vs {ν(CO)},
1719m {ν(CO)b}, 1606m {ν(CdO)}. 31P NMR (CDCl3): δ (ppm)
55.67 (JPt,P ) 2637 Hz), 50.35 (JPt,P ) 3684 Hz).
Preparation of [FePt(µ2-η1:η1:η2-TpCCCCTp-CO)(CO)-
(CO)2(dppe)], 3. In TLC separation processes of compound 2, an
eluent of another orange band, followed by recrystallization from
toluene, gave orange crystals (39 mg, 0.038 mmol; 15.2% yield/
platinum atom). Anal. Found: C, 53.39; H, 3.56. Calc for C42H30-
FeO4P2PtS2‚1/2(C6H5CH3): C, 53.48; H, 3.35. IR (CH2Cl2): ν˜
(cm-1) 2120s {ν(CtC)nonbonding}, 2016vs, 1956vs, 1819w {ν(CO)b},
1720m {ν(CdO)}, 1605m {ν(CdO)}. 31P NMR (CDCl3, δ): 55.70
(JPt,P ) 2608 Hz), 50.30 (JPt,P ) 3704 Hz). The same reaction was
carried out for 30 min, and the yield of 3 was slightly increased to
20%. 3, by leaving in toluene, CH3CN, or CH2Cl2 for several days,
at room temperature underwent decomposition.
Figure 6. ORTEP plot (50% probability thermal ellipsoids) of
FePt(µ2-η1:η1:η2-TpCCCCTp-CO)(µ-CO)(CO)2(dppe), 3. Phenyl
rings of dppe are omitted for clarity. Selected bond distances (Å)
and bond angles (deg): Pt1-Fe2 2.605(2), C3-C9 1.451(17), Pt1-
C1 2.087(12), Pt1-C10 2.346(15), C1-C2 1.454(18), Fe1-C1
2.052(10), C1-C3 1.381(17), Fe1-C3 2.192(12), O3-C9 1.232-
(18), O4-C10 1.146(18), C2-C4 1.226(19), Fe1-C9 1.935(14),
Fe1-C10 1.795(15), Fe1-Pt1-C1 50.4(3), Fe1-Pt1-C10 42.1-
(4), Pt1-Fe1-C10 61.2(5), Fe1-C9-C3 79.3(8), C1-C3-C9
108.3(10), Pt1-C1-C3 117.5(9), Pt1-C10-Fe1 76.7(5), C1-
Fe1-C3 37.8(5), C9-Fe1-C10 101.8(6).
support that compound 2 may also be formed via the intermedi-
ate of the π-complex of a 1,3-diyne, [Pt(η2-TpCtCCtCTp)-
(dppe)]. Any further details of the reactions are under further
investigation.
Crystal Structural Determinations. Intensity data were col-
lected by θ/2ω scans at 298 K using a INST_DIP2000 diffracto-
meter (Mac Science) on an imaging plate for compounds 1 and 3,
and an AFC 7 four-circle diffractometer for compound 2, with Mo
KR radiation (λ ) 0.7103 Å), and were corrected for Lorenz and
polarization effects. Structure solutions were performed by the direct
method using DIRDIF 9921 and WinGX 3.022 and by full-matrix
least squares on Fo with SHELXL.23 All non-hydrogen atoms were
refined anisotropically with H atoms in calculated positions riding
on C atoms with C-H fixed at 0.93 Å.
Crystal Structure Data of C46H30O8P2PtRu3S2, 1. A single
crystal was obtained by recrystallizing from CH3CN at 253 K;
monoclinic, space group P21/c, a ) 12.8680(0) Å, b ) 15.6720(0)
Å, c ) 25.2910(0) Å, R ) 90.0000(0)°, â ) 79.6770(0)°, γ )
90.0000(0)°, V ) 5017.81(0) Å3, Z ) 4, Dc ) 1.767 g‚cm-3, R1 )
0.0512, wR2 ) 0.1727, Goof (S) ) 1.0680 for 8555 independent
reflections, in the range 0° < 2θ < 51.41° with Fo > 4σ(Fo),
refining 7115 parameters.
Experimental Section
Preparation of Pt(CtCTp)2(dppe) (Tp ) 3-thiophene). To
PtCl2(dppe) (0.33 g, 0.5 mmol) in NEt2H and CH2Cl2 (1:1) were
added 3-ethynylthiophene (0.12 g, 1.1 mmol) and CuCl (10 mg,
0.1 mmol). The solution was refluxed overnight. After evaporation
of the solution, the residue was dissolved in CH2Cl2 and washed
by H2O in a separatory funnel. The CH2Cl2 phase, after drying over
anhydrous Na2SO4 and filtering the insoluble solid off, was reduced
in volume to 10 cm3, which on addition of hexane and standing at
room temperature for several minutes gave colorless crystals (0.35
g, 0.43 mmol; 86% yield/platinum atom). Anal. Found: C, 56.48;
H, 3.74. Calc for C38H30P2PtS2: C, 56.50; H, 3.74. IR (Nujol
mull): ν˜ (cm-1) 2122s. 31P NMR (CDCl3): δ (ppm) 41.69 (JPt,P
)
2282 Hz). 13C NMR (CDCl3): δ (ppm) 103.2 {CR, JP,C(trans) )
146.2 Hz; JP,C(cis) ) 15.71 Hz, JPt,C ) 1131.5 Hz}, 106.4 {Câ,
J
P,C(trans) ) 35.5 Hz; JPt,C ) 157.2 Hz}.
Crystal Structure Data of C42H30FeO4P2PtS2, 3. A single
crystal was obtained from a CH3CN-hexane solution at 253 K;
monoclinic, space group P21/n, a ) 14.6080(50) Å , b ) 23.7690-
(50) Å, c ) 11.9860(50) Å, R ) 90.000(5)°, â ) 90.564(5)°, γ )
90.000(5)°, V ) 4161.55(24) Å3, Z ) 4, Dc ) 1.557 g‚cm-3, R1 )
0.0431, wR2 ) 0.1401, Goof (S) ) 1.1490 for 6571 independent
reflections, in the range 0° < 2θ < 51.36° with Fo > 4σ(Fo),
refining 5855 parameters.
Preparation of [PtRu3{µ4-η1:η1:η1:η1:η4:η4-C4H2SCCC(H)-
CTp}(µ-CO)2(CO)6(dppe)], 1. To Pt(CtCTp)2(dppe) (190 mg,
0.24 mmol; Tp ) 3-thiophene) in toluene was added Ru3(CO)11(CH3-
CN) {in situ prepared by treating Ru3(CO)12 (130 mg, 0.2 mmol)
with NMe3dO‚H2O and CH3CN}. The solution was refluxed for
45 min. After cooling the solution, the solvent was evaporated to
(20) Liu, L.; Chang, K.; Wen, Y. J. Chin. Chem. Soc. 1997, 44, 33.
(21) Beurskens, P. T.; Beurskens, G.; de Gelder, R.; Carcia-Granada,
S.; Gould, R. O.; Israel, R.; Smits, J. M. M. The DIRDIF-99 program system;
Crystallography Laboratory, University of Nijmengen: The Netherlands,
1999.
(22) Farrujia, L. J. J. Appl. Crystallogr. 1999, 32, 837-838.
(23) Sheldrick, G. M. SHELXL-97; University of Go¨ttingen: Germany,
1997.
Supporting Information Available: Tables giving full crystal-
lographic details, positional and thermal parameters, and bond
distances and angles for 1, 2, and 3. This material is available free
of charge via the Internet at http://pubs.acs.org.
OM050748W