Osmium-bismuth complexes from the reaction of Os3(CO) 11(NCMe) with BiPh3

Article abstract of DOI:10.1021/ic100994t

Five new compounds were obtained from the reaction of Os ₃(CO)₁₁(NCMe), 1, with BiPh₃ in hexane solution at reflux. These have been identified as Os₂(CO)₈(μ- BiPh), 2, Os(CO)₄Ph₂, 3, Os₄(CO) ₁₄(μ-η³-O - CC₆H₅) (μ₄-Bi), 4, Os₄(CO)₁₅Ph(μ₄-Bi) , 5, and Os₅(CO)₁₉Ph(μ₄-Bi), 6. Cleavage of the phenyl groups from the BiPh₃ was the dominant reaction pathway. Fragmentation of the original triosmium cluster was accompanied by reaggregation processes that were facilitated by the naked bismuth to yield the higher nuclearity osmium cluster complexes containing spiro-bridging bismuth ligands. Compound 6 was photo-decarbonylated to yield the compound HOs ₅(CO)₁₈(μ-η²-C₆H ₄)(μ₄-Bi), 7, formed by ortho-CH activation of the σ-bonded phenyl ring in 6 to form a bridging η²-benzyne ligand. Compounds 2- 7 were each characterized structurally by a single-crystal X-ray diffraction analysis.

Full text of DOI:10.1021/ic100994t

7170 Inorg. Chem. 2010, 49, 7170–7175
DOI: 10.1021/ic100994t
Osmium-Bismuth Complexes from the Reaction of Os3(CO)11(NCMe) with BiPh3
Richard D. Adams* and William C. Pearl Jr.
Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208
Received May 18, 2010
Five new compounds were obtained from the reaction of Os3(CO)11(NCMe), 1, with BiPh3 in hexane solution at reflux. These
have been identified as Os2(CO)8(μ-BiPh), 2, Os(CO)4Ph2, 3, Os4(CO)14(μ-η3-OdCC6H5)(μ4-Bi), 4, Os4(CO)15-
Ph(μ4-Bi), 5, and Os5(CO)19Ph(μ4-Bi), 6. Cleavage of the phenyl groups from the BiPh3 was the dominant reaction pathway.
Fragmentation of the original triosmium cluster was accompanied by reaggregation processes that were facilitated by the naked
bismuth to yield the higher nuclearity osmium cluster complexes containing spiro-bridging bismuth ligands. Compound 6 was
photo-decarbonylated to yield the compound HOs5(CO)18(μ-η2-C6H4)(μ4-Bi), 7, formed by ortho-CH activation of the
σ-bonded phenyl ring in 6 to form a bridging η2-benzyne ligand. Compounds 2- 7 were each characterized structurally by a
single-crystal X-ray diffraction analysis.
Introduction
for the ammoxidation of 3-picoline to 3-cyanopyridine,
a precursor to niacin, also known as vitamin B3, under
unusually mild conditions, eq 3.8
Whitmire et al. have prepared and characterized a number of
interesting antimony and bismuth- transition metal cluster
compounds over the years.1-5 We have recently reported the
synthesis and characterization of a number of new rhenium
carbonyl complexes containing phenylantimony and phenyl-
bismuth ligands from the reactions of Re2(CO)8[μ-η2-C-
(H)dC(H)Bun](μ-H) with SbPh3 and BiPh3. The products of
these reactions contain bridging SbPh2 and BiPh2 ligands
formed by the facile cleavage of phenyl groups from the SbPh3
and BiPh3 reagents, eqs 16-27.
We have now turned some of our attention to the chemistry
of osmium carbonyl cluster complexes containing antimony
and bismuth. Leong et al. have investigated the thermal trans-
formations of the osmium-antimony compound Os3(CO)11-
(SbPh3).9 The products of those thermal transformations were
formed by cleavage of phenyl rings from the SbPh3 ligand. A
variety of osmium carbonyl cluster complexes containing
SbPh2, SbPh, and naked Sb ligands were obtained. Ang et al.
obtained three osmium-bismuth cluster complexes: H3Os3-
(CO)9(μ-Bi), Os3(CO)9Bi2, and Os4(CO)12Bi2 in low yields
from the reaction of Os3(CO)12 with NaBiO3.10 We have
now investigated the reaction of Os3(CO)11(NCMe), 1, with
BiPh3. Several new osmium-bismuth complexes have been
obtained including the first organobismuth-osmium carbonyl
complex Os2(CO)8(μ-BiPh), 2. The results of these studies are
reported herein.
We have also shown that some of these new rhenium-
antimony and rhenium-bismuth complexes are pre-
cursors to effective heterogeneous nanoscale catalysts
Experimental Section
*To whom correspondence should be addressed. E-mail: adams@mail.
chem.sc.edu.
General Data. All the reactions were performed under a
nitrogen atmosphere using the standard Schlenk techniques,
unless otherwise stated. Reagent grade solvents were dried by
(1) Whitmire, K. H. J. Cluster Sci. 1991, 2, 231–258.
(2) Luo, S. F.; Whitmire, K. H. J. Organomet. Chem. 1991, 30, 2788–2795.
(3) Cassidy, J. M.; Whitmire, K. H. Inorg. Chem. 2009, 48, 9519–9525.
(4) Bachman, R. E.; Whitmire, K. H. Inorg. Chem. 1995, 34, 1542–1551.
(5) Whitmire, K. H.; Evelan, J. R., Jr. J. Chem. Soc., Chem. Commun.
1994, 1335–1336.
(8) Raja, R.; Adams, R. D.; Blom, D. A.; Pearl, W. C., Jr.; Gianotti, E.;
Thomas, J. M. Langmuir 2009, 25, 7200–7204.
(6) Adams, R. D.; Captain, B.; Pearl, W. C., Jr. J. Organomet. Chem.
2008, 693, 1636–1644.
(7) Adams, R. D.; Pearl, W. C., Jr. Inorg. Chem. 2009, 48, 9519–9525.
(9) Leong, W. K.; Chen, G. Organometallics 2001, 20, 2280–2287.
(10) Ang, H. G.; Hay, C. M.; Johnson, B. F. G.; Lewis, J.; Raithby, P. R.;
Whitton, A. J. J. Organomet. Chem. 1987, 330, C5–C11.
r
pubs.acs.org/IC
Published on Web 07/08/2010
2010 American Chemical Society

Article
Inorganic Chemistry, Vol. 49, No. 15, 2010 7171
the standard procedures and were freshly distilled prior to use.
Infrared spectra were recorded on an AVATAR 360 FT-IR
spectrophotometer. 1H NMR spectra were recorded on Varian
Mercury 400 and 300 spectrometers operating at 399 and 300
MHz, respectively. Mass spectrometric measurements per-
formed by direct exposure probe using electron impact ioniza-
tion (EI) were made on a VG 70S instrument. Triphenylbismuth
(BiPh3) was purchased from STREM and was used without
further purification. Os3(CO)11NCMe, 1, was prepared accord-
ing to a previously published procedure.11 Product separations
were performed by thin layer chromatography (TLC) in air on
Conversion of 4 to 5. A 12.3 mg portion of 4 was dissolved in
10 mL of hexane and refluxed for 2 h. The solvent was removed in
vacuo, and the products were separated by TLC by using a 4:1
hexane/methylene chloride mixture to yield in order of elution an
orange band of unreacted 4, 2.6 mg (21%), and a red band of 5,
1.2 mg (10%).
Photoconversion of 6 to 7. A 6.0 mg portion of 6 was dissolved
in 10 mL of hexane, and the flask was placed in an ice bath while
photolyzing for 1 h using a 1000W UV lamp. The solvent was then
removed in vacuo, and the products were separated by TLC using a
4:1 hexane/methylene chloride mixture to yield in order of elution a
yellow band of Os3(CO)12, 3.5 mg (68% yield), an orange band of 7,
0.7 mg (12% yield), and a red band of unreacted 6, 0.6 mg (10%).
Carbonylation of 7. A 14.0 mg portion of 7was dissolved in 5 mL
of hexane and placed in a high pressure reactor under an atmosphere
of CO (250 psi) and heated at 60 °C for 1.5 h. After cooling, the
solvent was removed in vacuo, and the products were separated by
TLC by using a 4:1 hexane/methylene chloride (v/v) solvent mixture
to give 1.5 mg of Os4(CO)12(μ-Bi2)10 and 1.0 mg of 6 (7% yield).
Crystallographic Structural Analyses. Yellow single crystals
of 2, colorless crystals of 3, and red crystals of each of 4-7
suitable for X-ray diffraction analysis were obtained by slow
evaporation of solvent from solutions in methylene chloride/hexane
solvent at -25 °C. Each data crystal was glued onto the end of a thin
glass fiber. X-ray intensity data were measured by using a Bruker
SMART APEX CCD-based diffractometer by using Mo KR
˚
Analtech 0.50 mm silica gel 60 A F254 glass plates.
Reaction of 1 with BiPh3. A 100 mg portion (0.227 mmol) of
BiPh3 was added to a solution of 52.7 mg (0.0570 mmol) of 1
dissolved in 70 mL of hexane. The solution was then refluxed
for 3 h. After cooling, the solvent was removed in vacuo, and the
products were then separated by TLC using 4:1 hexane/methylene
chloride (v/v) solvent mixture to give in order of elution: a yellow
band of Os2(CO)8(μ-BiPh), 2, 3.5 mg (5% yield); a colorless band of
Os(CO)4Ph2, 3, 2.8 mg (5% yield); an orange band of Os4(CO)14(μ-
η2-OdCPh)(μ4-Bi), 4, 2.0 mg (3% yield); a red band of Os4-
(CO)15Ph(μ4-Bi), 5, 2.3 mg (4% yield); and an orange band of
Os5(CO)19Ph(μ4-Bi), 6, 1.6 mg (3% yield). Spectral data for 2 (νCO
cm-1 in hexane): 2112(w), 2069(s), 2035(vs), 2028 (vs), 2016 (m),
2004(m), 1990(w). 1H NMR (300 MHz, CD2Cl2, 25 °C, TMS) δ =
7.1-7.7 (m, 5H, Ph). Mass Spec. EI/MS m/z. 892 (Mþ), 864
(Mþ-CO), 836 (Mþ-2CO), 808 (Mþ-3CO). The isotope dis-
tribution pattern is consistent with the presence of one bismuth and
two osmium atoms. Spectral data for 3 (νCO cm-1 in hexane):
˚
radiation (λ = 0.71073 A). The raw data frames were integrated
with the SAINTþ program by using a narrow-frame integration
algorithm.12 Corrections for Lorentz and polarization effects were
also applied with SAINTþ. An empirical absorption correction
based on the multiple measurement of equivalent reflections was
applied for each analysis by using the program SADABS. All
structures were solved by a combination of direct methods and
difference Fourier syntheses, and refined by full-matrix least-squares
on F2 using the SHELXTL software package.13 All non-hydrogen
atoms were refined with anisotropic thermal parameters. Hydrogen
atoms on the ligands were placed in geometrically idealized positions
and included as standard riding atoms during the least-squares
refinements. Crystal data, data collection parameters, and results of
the refinements are listedinTable1. Compounds2and 4crystallized
in the triclinic crystal system. The space group P1 was assumed for
each and was confirmed by the successful solution and refinement of
the structures. In the crystal of 2, there is one complete independent
molecule of the complex in the asymmetric crystal unit. For 4, there
are two complete independent molecules in the asymmetric crystal
unit. Compound 3 crystallized in the orthorhombic crystal system.
The space group P212121 was confirmed on the basis of the
systematic absences observed in the data. Compound 3 contains
one independent molecule in the asymmetric crystal unit. Com-
pounds 5-7 all crystallized in the monoclinic crystal system. The
space group P21/n was confirmed for all three of these compounds
on the basis of the systematic absences observed in the data. The
crystal of 7 contains one formula equivalent of the complex in the
asymmetric crystal unit. The crystal of compound 6 contains one
independent molecule of the complex together with one molecule of
methylene chloride from the crystallization solvent in the asym-
metric crystal unit. The crystal of 7 contains one formula equivalent
of the complex in the asymmetric crystal unit. The hydrido ligand in
7 was located and refined on its positional parameters and an
isotropic thermal parameter.
1
2140(w), 2059(vs), 2027(s). H NMR (300 MHz, CDCl3, 25 °C,
TMS) 7.1-7.5(m, Ph, 10H), MassSpec. EI/MSm/z. 458 (Mþ), 402
(Mþ-2CO), 374 (Mþ-3CO). The isotope distribution pattern is
consistent with the presence of only one osmium atom. Spectral
data for 4 (νCO cm-1 in hexane): 2122(w), 2084(s), 2063(s),
2047(vs), 2031(m), 2021(w), 2005(w), 1992(m), 1984(w), 1971(vw),
1964(vw). 1H NMR (300 MHz, CD2Cl2, 25 °C, TMS) δ = 7.4-7.6
(m, 5H, Ph). Mass Spec. EI/MS m/z. 1468 (Mþ). The isotope
distribution pattern is consistent with the presence of one bismuth
and four osmium atoms. Spectral data for 5 (νCO cm-1 in hexane):
2124(w), 2090(m), 2084(s), 2069(vw), 2057(vs), 2047(m), 2041(s),
2034(m), 2025(m), 2022(m), 2016(m), 2004(vw), 1997(w), 1980(w).
1H NMR (300 MHz, CD2Cl2, 25 °C, TMS) δ = 7.3-7.8 (m, 5H,
Ph). Mass Spec. EI/MS m/z. 1468 (Mþ), 1440 (Mþ-CO). The
isotope distribution pattern is consistent with the presence of one
bismuth and four osmium atoms. Spectral data for 6 (νCO cm-1 in
hexane): 2123(w), 2098(s), 2078(vs), 2074(vs), 2057(m), 2042(w),
2038(m), 2031(m), 2017(s), 2010(w), 2004(w), 1990(w), 1984(w),
1971(vw). 1H NMR (300 MHz, CDCl3, 25 °C, TMS) δ = 6.9-7.7
(m, 5H, Ph). Mass Spec. EI/MS m/z. 1770 (Mþ), 1742 (Mþ-CO).
The isotope distribution pattern is consistent with the presence of
one bismuth and five osmium atoms.
Reaction of 1 with 2. A 5.2 mg portion (0.00582 mmol) of 2
was added to 5.5 mg (0.00595 mmol) of 1 dissolved in 5 mL of
hexane and refluxed for 45 min. The solvent was then removed in
vacuo, and the products were separated by TLC using 4:1 hexane/
methylene chloride (v/v) solvent mixture to give products in order
of elution, a yellow band of unreacted 2, 1 mg, an orange band of
HOs5(CO)18(μ-η2-C6H4)(μ4-Bi), 7, 1 mg (10%) and a red band of
6, 1.1mg(11%). Spectraldatafor7(νCO cm-1 in hexane): 2121(w),
2092(s), 2082(vs), 2078(s), 2061(w), 2045(vw), 2040(s), 2028(m),
2021(m), 2016(w), 2012(w), 2006(m), 1990(w), 1987(w). 1H NMR
(300 MHz, CDCl3, 25 °C, TMS) δ = 7.6 (d, Ph, 1H), 7.4 (d, Ph,
1H), 7.1 (t, Ph, 1H), 6.9 (t, Ph, 1H), -18.8 (s, hydride, 1H). Mass
Spec. EI/MS m/z. 1742 (Mþ), 1712 (Mþ-CO), 1686 (Mþ-2CO).
The isotope distribution pattern is consistent with the presence of
one bismuth and five osmium atoms.
Results
Five new compounds Os2(CO)8(μ-BiPh), 2, (5% yield), Os-
(CO)4Ph2, 3, (5% yield), Os4(CO)14(μ-η3-OdCC6H5)(μ4-Bi), 4,
(12) SAINTþ, Version 6.2a; Bruker Analytical X-ray System, Inc.: Madison,
WI, 2001.
(13) Sheldrick, G. M. SHELXTL, Version 6.1; Bruker Analytical X-ray
Systems, Inc.: Madison, WI, 1997.
(11) Johnson, B. F. G.; Lewis, J.; Pippard, D. A. J . Chem. Soc., Dalton
Trans. 1981, 407–412.

7172 Inorganic Chemistry, Vol. 49, No. 15, 2010
Adams and Pearl
Table 1. Crystallographic Data for the Structural Analyses of Compounds 2-7
2
3
4
5
6
7
empirical formula
formula weight
crystal system
Os2BiO8C14H5
890.56
triclinic
OsO4C16H10
456.44
orthorhombic
Os4BiO15C21H5
1467.03
triclinic
Os4BiO15C21H5
1467.03
monoclinic
Os5BiO19C25H5 CH2Cl2
1854.20
monoclinic
Os5BiO18C24H4
1740.25
monoclinic
3
lattice parameters
˚
˚
b (A)
˚
c (A)
a (A)
9.5596(8)
10.0335(8)
10.7117(9)
94.491(2)
106.687(2)
104.987(2)
937.67(13)
P1
2
3.154
22.913
294(2)
57.06
3548
226
0.970
0.001
0.0328; 0.0663
1.000; 0.403
7.7405(3)
12.6633(5)
15.6545(6)
90.00
90.00
90.00
1534.46(10)
P212121
4
1.976
8.321
294(2)
56.66
3396
190
1.018
0.001
0.0265; 0.0513
1.000/0.736
12.953(3)
15.314(4)
15.976(4)
71.752(4)
80.406(4)
88.175(5)
2966.8(12)
P1
4
3.284
23.046
294(2)
52.74
6345
739
0.942
0.001
0.0668; 0.1323
0.322/1.000
10.8919(4)
17.0759(6)
16.1745(6)
90.00
103.3050(10)
90.00
2927.53(18)
P21/n
4
3.328
23.355
294(2)
56.72
5599
370
1.015
0.001
0.0299; 0.0613
1.000/0.568
16.9824(6)
9.7637(3)
23.9049(8)
90.00
100.6750(10)
90.00
3895.1(2)
P21/n
4
3.162
20.957
294(2)
52.74
6803
478
1.069
0.002
0.0493; 0.1547
1.000/0.228
9.6781(4)
21.3846(8)
15.9979(6)
90.00
94.4480(10)
90.00
3301.0(2)
P21/n
4
3.502
24.558
294(2)
56.88
5585
433
1.050
0.001
0.0497; 0.0727
1.000/0.513
R (deg)
β (deg)
γ (deg)
3
˚
V (A )
space group
Z value
F
calc (g/cm3)
μ (Mo KR) (mm-1
temperature (K)
2Θmax (deg)
)
no. obs. (I > 2σ(I))
no. parameters
goodness of fit
max. shift in cycle
residualsa: R1; wR2
absorption correction,
max/min
largest peak in final
1.371
0.870
2.381
1.961
3.341
1.775
-
3
diff. map (e /A )
˚
P
P
P
P
P
a R1 = hkl(||Fobs| - |Fcalc||)/ hkl|Fobs|; wR2 = [ hklw(|Fobs| - |Fcalc|)2/ hklwFobs
]
2 1/2, w = 1/σ2(Fobs); GOF = [ hklw(|Fobs| - |Fcalc|)2/(ndata - nvari)]1/2
.
Figure 2. ORTEP diagram of the molecular structure of Os(CO)4Ph2, 3
showing 30% probability thermal ellipsoids. The hydrogen atoms on the
˚
ligands are omitted for clarity. Selected interatomic bond distances (A)
and angles (deg) are as follow: Os(1)-C(7) = 2.175(5), Os(1)-C(1) =
2.182(5), Os(1)-C(15) = 1.945(6), Os(1)-C(13) = 1.947(6), Os(1)-C-
(14) = 1.957(6), Os(1)-C(16) = 1.967(7); C(7)-Os(1)-C(1) = 90.6(2).
˚
Os(1)-Os(2)=2.9512(5) A, is slightly longer than that found in
Os3(CO)12, 2.877(3) A.14 The Os-Bi distances, Os(1)-Bi(1)=
˚
Figure 1. ORTEP diagram of the molecular structure of Os2(CO)8-
(μ-BiPh), 2, showing 30% probability thermal ellipsoids. The hydrogen
atoms on the ligands are omitted for clarity. Selected interatomic bond
˚
˚
2.8305(4) A, Os(2)-Bi(1) = 2.8270(5) A, are slightly longer
than Os-Bi distances to the triply bridging Bi ligand in H3Os3-
˚
˚
˚
distances (A) and angles (deg) are as follow: Os(1)-Os(2) = 2.9512(5),
(CO)9(μ-Bi), 2.800(2) A; Bi(l)-Os(2), 2.807(l) A; Bi(l)-Os(3),
2.799(2) A.10 The bridging monophenylbismuth ligand serves a
Os(1)-Bi(1)=2.8305(4), Os(2)-Bi(1) = 2.8270(5), Bi(1)-C(1)=2.269(7);
Bi(1)-Os(1)-Os(2)=58.500(12), Bi(1)-Os(2)-Os(1)=58.614(11), C(1)-
Bi(1)-Os(2) = 106.79(19), C(1)-Bi(1)-Os(1) = 99.83(18).
˚
two electron donor to the osmium atoms in 2 and with an
Os-Os bond each of the osmium atoms achieves an 18 electron
configuration. The BiPh ligand has been observed previously in
(3% yield), Os4(CO)15Ph(μ4-Bi), 5, (4% yield), and Os5(CO)19-
Ph(μ4-Bi), 6, (3% yield) were obtained all in low yields from the
reaction of 1 with BiPh3 in a hexane solution at reflux (68 °C)
over a 3 h period. All five compounds were characterized by a
combination of IR, NMR, mass spec and single crystal X-ray
diffraction analyses. An Oak Ridge thermal ellipsoid plot
(ORTEP) diagram of the molecular structure of 2 is shown in
Figure 1. Compound 2contains two osmium atoms, eight linear
terminal carbonyl ligands, and a BiPh ligand that bridges the
osmium-osmium bond. The osmium-osmium bond distance,
the complexes Re2(CO)8(μ-BiPh)2 and Fe2(CO)8(μ-BiPh)2.2
7
The former complex has a metal-metal bond while the latter
complex does not.
An ORTEP diagram of the structure of the coproduct 3 is
shown in Figure 2. The molecule contains one osmium atom,
two σ-bonded phenyl rings and four linear terminal carbonyl
groups. The six ligands exhibit an octahedral-type coordina-
tion geometry with the two phenyl rings in cis-related
sites. The angle between the phenyl rings is very close to
90°, C(7)-Os(1)-C(1) = 90.6(2)o. As expected, the Os-C
˚
distances to the phenyl rings, Os(1)-C(7)=2.175(5) A and
(14) Churchill, M. R.; DeBoer, B. G. Inorg. Chem. 1977, 16, 878.

Article
Inorganic Chemistry, Vol. 49, No. 15, 2010 7173
Figure 3. ORTEP diagram of the molecular structure of Os4(CO)14(μ-η3-OCC6H5)(μ4-Bi), 4, showing 30% probability thermal ellipsoids. The hydrogen
˚
atoms on the ligands are omitted for clarity. Selected interatomic bond distances (A) and angles (deg) are as follow: Os(1)-Os(2) = 2.8238(14), Os(3)-
Os(4) = 2.9691(14), Os(1)-Bi(1) = 2.7230(14), Os(2)-Bi(1) = 2.7065(13), Os(3)-Bi(1) = 2.7531(15), Os(4)-Bi(1) = 2.7514(13), Os(1)-C(1) = 2.06(2),
Os(2)-O(1) = 2.133(15); C(1)-Os(1)-Bi(1) = 79.2(7), C(1)-Os(1)-Os(2) = 66.6(7), Bi(1)-Os(1)-Os(2) = 58.38(3), O(1)-Os(2)-Bi(1) = 82.0(4),
O(1)-Os(2)-Os(1) = 69.4(4), Bi(1)-Os(2)-Os(1) = 58.95(3), Bi(1)-Os(3)-Os(4) = 57.33(3), Bi(1)-Os(4)-Os(3) = 57.39(3).
˚
Os(1)-C(1)=2.182(5) A, are significantly longer than the
complexes containing bridging bismuth atoms in the spiro-
coordination form. Johnson et al. reported the pentaruthenium
complex HRu5(CO)18(μ4-Bi), 8, which contains a spiro-μ4-Bi
bridging a Ru2(CO)8 group and HRu3(CO)11 group.17 Leong
has reported some osmium carbonyl cluster complexes contain-
ing spiro-Sb atoms.9
˚
Os-C distances to the CO ligands, Os(1)-C(15)=1.945(6) A,
˚
˚
Os(1)-C(13)=1.947(6) A, Os(1)-C(14)=1.957(6) A, Os-
˚
(1)-C(16) = 1.967(7) A. There are no previous reports of
structural characterizations of bis-arylosmium tetracarbonyl
complexes, but there is a report of a bis-(pentafluorobenzyl)-
osmium tetracarbonyl complex, Os(CO)4(CH2C6F5)2, which
has a similar structure.15 There are number of related di-σ-
alkylosmium tetracarbonyl complexes.16
An ORTEP diagram of the structure of 4 is shown in
Figure 3. This compound contains four osmium atoms con-
tained in two groups of two that are linked by a spiro-bridging
bismuth atom, Bi(1). One of the pair of osmium atoms is an
Os2(CO)8 group that contains an Os-Os bond, Os(3)-
˚
An ORTEP diagram of the structure of 5 is shown in
Figure 4. This compound is similar to 4. It contains four osmium
atoms contained in two groups of two that are also linked by a
spiro-bridging bismuth atom, Bi(1). One of the pair of the
osmium atoms is a Os2(CO)8 group that contains an Os-Os
bond that is very similar in length to that found in 4, Os(3)-
Os(4)=2.9691(14) A. The other group is an Os2(CO)6 group
˚
that has an Os-Os bond, Os(1)-Os(2)=2.8238(14) A, and a
bridging benzoyl ligand that is C-coordinated to one osmium
˚
atom, Os(1)-C(1) = 2.06(2) A, and O-coordinated to the
˚
other osmium atom, Os(2)-O(1)=2.133(15) A. The osmium-
bismuth bonds are significantly shorter, Os(1)-Bi(1) =
˚
˚
˚
Os(4)=2.9734(4) A. The second Os2 group is an Os2(CO)7Ph
2.7230(14) A, Os(2)-Bi(1) = 2.7065(13) A, Os(3)-Bi(1) =
˚
˚
group that contains a σ-bonded phenyl group in an axial site on
one of the metal atoms. The Os-C distance, Os(1)-C(1) =
2.7531(15) A, Os(4)-Bi(1)=2.7514(13) A, than the osmium-
bismuth bonds in 2. The Os-Bi bonds to the Os2(CO)6-
(μ-O=CPh) group are significantly shorter than those to the
Os2(CO)8 group. The spiro μ4-Bi atom serves as a 5-electron
donor to the metal atoms. With a proper distribution of those
five electrons, each of the osmium atoms achieves an 18-
electron configuration. There are very few examples of metal
˚
2.178(7) A, is very similar to those in 3. There is also an Os-Os
bond in this Os2 group that is very similar in length, Os(1)-
˚
Os(2)=2.9759(4) A, to that in the Os2(CO)8 group. The Os-Bi
distances are similar to those in 4, Os(1)-Bi(1) = 2.7159(3),
Os(2)-Bi(1) = 2.7596(4), Os(3)-Bi(1) = 2.7635(4), Os(3)-
Os(4) =2.9734(4), Os(4)-Bi(1) = 2.7705(4). Each of the os-
mium atoms in 5 has a formal 18-electron configuration.
(15) Aleksandrov, G. G.; Zolnikov, G. P.; Kritskaya, I. I.; Struchkov,
Y. T. Koord. Khim. 1980, 6, 629.
(16) Lindner, E.; Ayasse, C. S.; Eichele, K.; Steinmann, M. Organome-
tallics 2002, 21, 4217–4225.
(17) Johnson, B. F. G.; Lewis, J.; Raithby, P. R.; Whitton, A. J. J. Chem.
Soc., Chem. Commun. 1988, 401–402.

7174 Inorganic Chemistry, Vol. 49, No. 15, 2010
Adams and Pearl
Figure 6. ORTEP diagram of the molecular structure of HOs5(μ-C6H4)-
(μ4-Bi)(CO)18, 7, showing 30% probability thermal ellipsoids. The hydrogen
atoms on the ligands are omitted for clarity. Selected interatomic bond dis-
˚
tances (A) and angles (deg) are as follow: Os(1)-C(2) = 2.110(11), Os(1)-
Bi(1)=2.7914(6), Os(1)-Os(2)=3.1457(6), Os(1)-H(1)=1.78(70), Os(2)-
C(1)=2.132(12), Os(2)-Os(3) =2.9753(7),Os(2)-H(1) = 1.67(7), Os(3)-
Bi(1) = 2.8130(6), Os(4)-Bi(1) = 2.8178(6), Os(4)-Os(5) = 2.9643(7),
Os(5)-Bi(1) = 2.7682(6); C(2)-Os(1)-Bi(1) = 79.1(3), C(2)-Os(1)-Os-
(2) = 65.9(3), Bi(1)-Os(1)-Os(2) = 79.615(16), C(2)-Os(1)-H(1) =
89(2), Bi(1)-Os(1)-H(1) = 81(2), Os(2)-Os(1)-H(1) = 23(2), C(1)-Os-
(2)-Os(3)=93.1(3), C(1)-Os(2)-Os(1)=65.9(3), Os(3)-Os(2)-Os(1) =
91.646(17), Os(3)-Os(2)-H(1)=87(2), Os(1)-Os(2)-H(1)=25(2), Bi(1)-
Os(3)-Os(2) = 82.298(17), Bi(1)-Os(4)-Os(5) = 57.140(15), Bi(1)-
Os(5)-Os(4)=58.765(15), Os(5)-Bi(1)-Os(1)=124.76(2), Os(5)-Bi(1)-
Os(3) = 123.01(2), Os(1)-Bi(1)-Os(3) = 103.176(19), Os(5)-Bi(1)-
Os(4) = 64.095(17), Os(1)-Bi(1)-Os(4) = 119.302(19), Os(3)-Bi(1)-
Os(4)=119.41(2).
Figure 4. ORTEP diagram of the molecular structure of Os4(CO)15
Ph(μ4-Bi), 5, showing 30% probability thermal ellipsoids. The hydro-
gen atoms on the ligands are omitted for clarity. Selected interatomic
-
˚
bond distances (A) and angles (deg) are as follow: Os(1)-C(1) =
2.178(7), Os(1)-Bi(1)=2.7159(3), Os(1)-Os(2)=2.9759(4), Os(2)-Bi(1)=
2.7596(4), Os(3)-Bi(1)=2.7635(4), Os(3)-Os(4)=2.9734(4), Os(4)-Bi(1)=
2.7705(4); C(1)-Os(1)-Bi(1)=91.15(17), C(1)-Os(1)-Os(2)=87.16(17),
Bi(1)-Os(1)-Os(2) =57.788(9), Bi(1)-Os(2)-Os(1) =56.375(9), Bi(1)-
Os(3)-Os(4)=57.612(9), Bi(1)-Os(4)-Os(3)=57.387(9), Os(1)-Bi(1)-
Os(2) = 65.838(10), Os(1)-Bi(1)-Os(3) = 141.906(13), Os(2)-Bi(1)-
Os(3) = 125.747(13), Os(1)-Bi(1)-Os(4) = 142.150(14), Os(2)-Bi(1)-
Os(4)=127.441(13), Os(3)-Bi(1)-Os(4)=65.000(10).
Os3(CO)11Ph group. The two groups are linked by a spiro-
bridging bismuth atom, Bi(1). The Os-Os bond distance in
the Os2(CO)8 group is similar in length to those found in 4
˚
and 5, Os(1)-Os(2) = 2.9625(6) A. The Os3(CO)11Ph group,
Os(3)-Os(5), is an “open” cluster. The terminal osmium
atoms Os(3) and Os(5) are bonded to the spiro-Bi atom. Os(3)
and Os(4) have four linear terminal carbonyl ligands. Os(5)
has three linear terminal carbonyl ligands and a σ-bonded
phenyl group that is coordinated trans to the Bi atom. The
Os-C distance to the σ-bonded phenyl group, Os(5)-C(1) =
˚
2.152(13) A, is similar in length to those in 3 and 5. There are
two Os-Os bonds in the Os3(CO)11Ph group, Os(3)-Os(4) =
˚
˚
2.9870(7) A, Os(4)-Os(5) = 3.0167(6) A, which are signifi-
cantly longer than those in the triangular cluster Os3(CO)12,
14
˚
˚
2.877(3) A. The Os-Bi distances, Os(1)-Bi(1)=2.8216(6) A,
˚
˚
Os(2)-Bi(1) = 2.7850(6) A, Os(3)-Bi(1) = 2.8368(6) A, and
˚
Os(5)-Bi(1) = 2.7922(6) A, are similar to those in com-
pounds 3- 5. Each of the osmium atoms in 6 formally has an
18-electron configuration. Compounds 6 and 7 were both
obtained in low yields from the reaction of 1 with 2. Com-
pound 6 was also converted to 7 upon exposure to UV-vis
irradiation.
Figure 5. ORTEP diagram of the molecular structure of Os5(CO)19Ph-
(μ4-Bi), 6, showing 30% probability thermal ellipsoids. The hydrogen atoms
on the ligands are omitted for clarity. Selected interatomic bond distances
˚
(A) and angles (deg) are as follow: Os(1)-Bi(1)=2.8216(6), Os(1)-Os(2)=
2.9625(6), Os(2)-Bi(1) = 2.7850(6), Os(3)-Bi(1) = 2.8368(6), Os(3)-Os-
(4)=2.9870(7), Os(4)-Os(5)=3.0167(6), Os(5)-C(1)=2.152(13), Os(5)-
Bi(1)=2.7922(6); Bi(1)-Os(1)-Os(2)=57.505(15), Bi(1)-Os(2)-Os(1)=
58.705(15), Bi(1)-Os(3)-Os(4) = 77.855(16), Os(3)-Os(4)-Os(5) =
94.008(17), C(1)-Os(5)-Bi(1) = 174.0(3), C(1)-Os(5)-Os(4)=96.6(3),
Bi(1)-Os(5)-Os(4) = 78.035(17), Os(2)-Bi(1)-Os(5) = 123.113(19),
Os(2)-Bi(1)-Os(1) = 63.789(16), Os(5)-Bi(1)-Os(1) = 126.943(18),
Os(2)-Bi(1)-Os(3) = 119.465(19), Os(5)-Bi(1)-Os(3) = 102.537(18),
Os(1)-Bi(1)-Os(3) = 118.663(19).
An ORTEP diagram of the structure of 7 is shown in
Figure 6. Like 6, compound 7 contains five osmium atoms
divided into two groups; one group contains two metal atoms
˚
in an Os2(CO)8 group, Os(4)-Os(5) = 2.9643(7) A, and the
other three in an Os3(CO)10(μ-η2-C6H4)(μ-H) cluster. The
Os3 cluster is open as it was in 6 and it contains a rare example
of a parallel coordinated μ-η2-C6H4 ligand across the Os(1)-
˚
Os(2) bond, Os(1)-C(2) = 2.110(11) A, Os(2)-C(1) =
˚
An ORTEP diagram of the structure of 6 is shown in
Figure 5. Compound 6 contains five osmium atoms divided
into two groups; one group contains two metal atoms in the
form of an Os2(CO)8 group, and the other three in an
2.132(12) A. The Os-Os bond is unusually long, Os(1)-
˚
Os(2) = 3.1457(6) A, because of the presence of a bridging
hydride ligand H(1) on the other side of this bond. Bridging
hydride ligands are well-known to cause lengthening of their

Article
Inorganic Chemistry, Vol. 49, No. 15, 2010 7175
Scheme 1
associated metal-metal bonds.18 The hydride ligand in 7 was
located and refined in the crystal structure analysis. As
expected, it exhibits a high-field resonance shift, δ =
confirmed in this study. It appears that 4 and 5 could be
formed from 2 in some way, but we have not yet been able
confirm this. We have been able to obtain 5 from 4 in a low
yield by a shift of the phenyl group from the CO of the benzoyl
ligand to one of the osmium atoms at the same temperature at
which the original reaction was performed, so it seems likely
that 4 is a precursor to 5 in the original reaction. Compound 6
appears to have been formed by a combination of 2 with an
additional quantity of 1 in the original reaction mixture and
that was supported by our independent synthesis of 6 and 7
from 2 and 1 under the same conditions as the original reaction
of 1 with BiPh3. The photodecarbonylation of 6 leads to an
ortho-metalation of the σ-bonded phenyl ring to form the
bridging η2-C6H4 benzyne ligand and the bridging hydride
ligand in 7. Conversely, it is possible to obtain 6 in low yield
(7%) together with a small amount of Os4(CO)12(μ-Bi2)10
from 7 by heating a solution of 6 in hexane solvent to 60 °C
under a slight pressure of CO (250 psi). It is anticipated that a
range of new osmium-bismuth carbonyl complexes will be
accessible from reactions of BiPh3 with the known family of
MeCN-labilized osmium carbonyl cluster complexes.19 Further
studies are in progress.
1
-18.8, in the H NMR spectrum of 7. The other Os-Os
bond in the trisomium group has a normal length, Os(2)-
˚
Os(3) = 2.9753(7) A, that is similar to that found in 6. The
Os-Bi distances to the spiro-bridging Bi ligand are similar
˚
to those in 4-6, Os(1)-Bi(1)=2.7914(6) A, Os(3)-Bi(1)=
˚
˚
2.8130(6) A, Os(4)-Bi(1)=2.8178(6) A and Os(5)-Bi(1)=
˚
2.7682(6) A. Each of the osmium atoms in 7 has an 18-
electron configuration.
Discussion
A summary of the reactions and products obtained in this
study are shown in the Scheme 1. The reaction of 1 with BiPh3
results in the formation of five new compounds by fragmen-
tation of the Os3 cluster of 1 and the cleavage of phenyl rings
from the BiPh3. No triosmium and no BiPh3 containing
products were obtained. Compound 2 contains two osmium
atoms and one bridging BiPh ligand while compound 3
contains only one osmium atom and two phenyl rings,
presumably the same osmium atom and the two rings that
were cleaved from the BiPh3 in the formation of 2, but this is
not certain since the mechanism of the reaction was not
Acknowledgment. This research was supported by the
USC NanoCenter and the National Science Foundation
under Grant CHE-0743190 and the USC NanoCenter.
(18) Bau, R.; Drabnis, M. H. Inorg. Chim. Acta 1997, 259, 27–50. (b)
Teller, R. G.; Bau, R. Struct. Bonding 1981, 41, 1–82.
(19) (a) Dawson, P. A.; Johnson, B. F. G.; Lewis, J.; Puga, J.; Raithby,
P. R.; Rosales, M. J. J. Chem. Soc., Dalton Trans. 1982, 233–235. (b) Choi,
Y. Y.; Wong, W. T. J. Organomet. Chem. 1997, 542, 121–129.
Supporting Information Available: CIF files for each of the
structural analyses. This material is available free of charge via
the Internet at http://pubs.acs.org.