Synthesis and structural characterization of group 10 metal-carboryne complexes

Article abstract of DOI:10.1021/om100669x

A series of group 10 metal-carboryne complexes were prepared from an equimolar reaction of MCl₂(PR₃)₂ with Li ₂C₂B₁₀H_10-nX_n (M = Ni, Pd, Pt; X = Br, I, Ph; n = 0, 1, 2). They were fully characterized by various spectroscopic techniques, elemental analyses, and X-ray diffraction studies. These complexes have similar solid-state structures, in which the metal atom is bonded to two cage carbon atoms and coordinated to two phosphorus atoms in a planar geometry. The coordinated phosphines are labile and can be replaced by other Lewis bases. The bonding interactions between the metal and the carboryne unit can be described as a resonance hybrid of both the M-C σ- and M-C π-bonding forms. These complexes can be viewed as 16e species.

Full text of DOI:10.1021/om100669x

Organometallics 2010, 29, 4541–4547 4541
DOI: 10.1021/om100669x
Synthesis and Structural Characterization of Group 10
Metal-Carboryne Complexes
†
Zaozao Qiu, Liang Deng, Hoi-Shan Chan, and Zuowei Xie*
†
†
,†,‡
†
Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong,
‡
People’s Republic of China, and State Key Laboratory of Elemento-Organic Chemistry, Nankai University,
Tianjin, People’s Republic of China
Received July 9, 2010
A series of group 10 metal-carboryne complexes were prepared from an equimolar reaction of
MCl (PR ) with Li C B H
X (M = Ni, Pd, Pt; X = Br, I, Ph; n = 0, 1, 2). They were fully
n
2
3 2
2
2
10 10-n
characterized by various spectroscopic techniques, elemental analyses, and X-ray diffraction studies.
These complexes have similar solid-state structures, in which the metal atom is bonded to two cage
carbon atoms and coordinated to two phosphorus atoms in a planar geometry. The coordinated
phosphines are labile and can be replaced by other Lewis bases. The bonding interactions between the
metal and the carboryne unit can be described as a resonance hybrid of both the M-C σ- and M-C
π-bonding forms. These complexes can be viewed as 16e species.
Introduction
1 equiv of alkenes to generate alkenylcarborane coupling
6
products, and undergo three-component [2þ2þ2] cyclotri-
Carboryne (1,2-dehydro-o-carborane), a three-dimensional
relative of benzyne, was first reported in 1990 as a very reactive
merization with 1 equiv of activated alkene and 1 equiv of
7
alkyne to give dihydrobenzocarboranes. The reaction of car-
1
intermediate. Subsequent reactivity studies showed that it can
boryne with alkynes can also proceed in a catalytic manner using
8
react with alkenes, dienes, alkynes, and aromatics in [2þ2] and
Ni species as catalyst. In contrast, the zirconium-carboryne
2
[
4þ2] cycloaddition and ene-reaction patterns, similar to that
precursor Cp Zr(μ-Cl)(μ-C B H )Li(OEt ) reacts with only
2
2
10 10
2 2
3
9
1 equiv of alkynes or polar unsaturated organic substrates such
as isonitrile, nitrile, and azide to give monoinsertion products
of benzyne. These carboryne reactions are usually complicated
and not in a controlled manner. On the other hand, metal-
carboryne complexs can react efficiently with various unsatu-
rated molecules to produce organic and organometallic com-
pounds incorporating a carboranyl unit. For example,
10
even in the presence of excess substrates.
The aforementioned results suggest that the reactivity
patterns of metal-carboryne complexes are largely depen-
dent upon the nature of the transition metals. Although one
2
4
nickel-carboryne complex (η -C B H )Ni(PPh ) can
2
10 10
3 2
4
11,12
undergo regioselective [2þ2þ2] cycloaddition reactions
Ni-carboryne and several Zr-carboryne complexes
5
with 2 equiv of alkynes to afford benzocarboranes, react with
have been structurally characterized, other transition metal-
carboryne complexes are either unknown or partially char-
1
3
*
To whom correspondence should be addressed. Fax: (852)26035057.
Tel: (852)26096269. E-mail: zxie@cuhk.edu.hk.
1) Gingrich, H. L.; Ghosh, T.; Huang, Q.; Jones, M., Jr. J. Am.
Chem. Soc. 1990, 112, 4082.
2) (a) Ghosh, T.; Gingrich, H. L.; Kam, C. K.; Mobraaten, E. C. M.;
Jones, M., Jr. J. Am. Chem. Soc. 1991, 113, 1313. (b) Huang, Q.; Gingrich,
H. L.; Jones, M., Jr. Inorg. Chem. 1991, 30, 3254. (c) Cunningham, R. T.;
Bian, N.; Jones, M., Jr. Inorg. Chem. 1994, 33, 4811. (d) Ho, D. M.;
Cunningham, R. J.; Brewer, J. A.; Bian, N.; Jones, M., Jr. Inorg. Chem.
acterized without NMR data. As an ongoing project, we
are interested in the effects of cage substituents, co-ligands,
and the nature of transition metals on the formation,
structure, and stability of metal-carboryne complexes. We
report here the synthesis and structural characterization
of a variety of group 10 metal-1,2-o-carboryne complexes
(
(
1
995, 34, 5274. (e) Barnett-Thamattoor, L.; Zheng, G.; Ho, D. M.; Jones, M.,
(7) Qiu, Z.; Xie, Z. J. Am. Chem. Soc. 2009, 131, 2084.
(8) Qiu, Z.; Wang, S. R.; Xie, Z. Angew. Chem., Int. Ed. 2010, 49,
4649.
(9) (a) Ren, S.; Chan, H.-S.; Xie, Z. J. Am. Chem. Soc. 2009, 131,
3862. (b) Ren, S.; Chan, H.-S.; Xie, Z. Organometallics 2009, 28, 4106.
(10) Deng, L.; Chan, H.-S.; Xie, Z. J. Am. Chem. Soc. 2005, 127,
13774.
Jr.; Jackson, J. E. Inorg. Chem. 1996, 35, 7311. (f) Atkins, J. H.; Ho, D. M.;
Jones, M., Jr. Tetrahedron Lett. 1996, 37, 7217. (g) Jeon, J.; Kitamura, T.;
Yoo, B.-W.; Kang, S. O.; Ko, J. Chem. Commun. 2001, 2110. (h) Lee, T.;
Jeon, J.; Song, K. H.; Jung, I.; Baik, C.; Park, K.-M.; Lee, S. S.; Kang, S. O.;
Ko, J. Dalton Trans. 2004, 933. (i) Wang, S. R.; Qiu, Z.; Xie, Z. J. Am.
Chem. Soc. 2010, 132, 9988.
(
3) (a) Dyke, A. M.; Hester, A. J.; Lloyd-Jones, G. C. Synthesis 2006, 24,
093. (b) Pellissier, H.; Santelli, M. Tetrahedron 2003, 59, 701. (c) Hoffmann,
R. W. Dehydrobenzene and Cycloalkynes; Academic Press: New York, 1967.
d) Franzen, V.; Joschek, H. I. Ann. 1967, 703, 90. (e) Jones, M., Jr.; Levin, R. H.
J. Am. Chem. Soc. 1969, 91, 6411.
4) Only the X-ray structure was reported and no NMR data were
(11) Wang, H.; Li, H.-W.; Huang, X.; Lin, Z.; Xie, Z. Angew. Chem.,
Int. Ed. 2003, 42, 4347.
(12) Ren, S.; Deng, L.; Chan, H.-S.; Xie, Z. Organometallics 2009, 28,
5749.
2 10 n 3
(13) (C B H10)ML (M = Pd, Pt, L = PPh , n = 2; M = Co, L =
bipy, n = 1) were reported without NMR data; see: (a) Zakharkin, L. I.;
Kovredov, A. I. Izv. Akad. Nauk. SSSR, Ser. Khim. 1975, 2619. (b)
Ol'dekop, Yu. A.; Maier, N. A.; Erdman, A. A.; Prokopovich, V. P. Zh.
Obshch. Khim. 1982, 52, 2256. (c) Ol'dekop, Yu. A.; Maier, N. A.; Erdman,
A. A.; Prokopovich, V. P. Dokl. Akad. Nauk. SSSR 1981, 257, 647.
4
(
(
available; see: Sayler, A. A.; Beall, H.; Sieckhaus, J. F. J. Am. Chem.
Soc. 1973, 95, 5790.
(
(
5) Deng, L.; Chan, H.-S.; Xie, Z. J. Am. Chem. Soc. 2006, 128, 7728.
6) Qiu, Z.; Xie, Z. Angew. Chem., Int. Ed. 2008, 47, 6572.
r 2010 American Chemical Society
Published on Web 09/23/2010
pubs.acs.org/Organometallics

4
542 Organometallics, Vol. 29, No. 20, 2010
Qiu et al.
Scheme 1. Synthesis of Group 10 Metal-Carboryne Complexes
Scheme 2. Synthesis of B-Substituted Nickel-Carboryne
Complexes
carboranes and the Ni(0) species in refluxing THF. It is
suggested that both 3-phenyl and the sterically demanding
PPh ligands contribute to the exceptional stability of 10.
3
Complexes 1-10 are highly soluble in THF and slightly
soluble in ether and toluene.
All complexes were fully characterized by various spectro-
with different cage B-substituents or different phosphine
ligands.
1
13
scopic techniques and elemental analyses. The H and
C
NMR spectra, which displayed only the signals of cage
substituents and phosphine ligands, do not give much
information on the solution structures. The cage carbons were
Results and Discussion
Synthesis. Salt metathesis between Li C B H and metal
2
2 10 10
11
halides is a useful method for the preparation of metal-
not observed for all complexes. The B NMR spectra exhi-
bited 2:4:4, 2:1:3:4, 3:4:3, 2:2:6, 2:2:6, 3:6:1, 2:6:2, 1:1:3:1:2:2,
1:1:1:2:5, and 1:1:1:3:4 patterns for 1-10, respectively. In
addition, one singlet at -22.9 ppm corresponding to the BI
vertex in 6 and one resonance at -21.6 ppm assignable to the
carboryne complexes. Treatment of Li C B H with
1
2
2 10 10
equiv of MCl (PPh ) in THF or diethyl ether at 0 °C gave,
2
3 2
2
after workup, (η -C B H )M(PPh ) (M = Ni (1), Pd (2),
2
10 10
3 2
Pt (3)) as red or yellow crystals in 60-72% isolated yields
4
,13
2
1
11
(
Scheme 1). In a similar manner, complexes (η -C B H )-
two BI vertices in 7 were observed in their H coupled B NMR
spectra. The BBr signal of 8 was observed as a singlet at -11.6
ppm. The BPh signal was exhibited as a singlet at -3.8 and -0.8
2
10 10
2
Ni(PMe ) (4) and (η -C B H )Ni(dppe) (5) (dppe = 1,2-
3
2
2 10 10
bis(diphenylphosphino)ethane) were also synthesized as yellow
crystals from the interaction of Li C B H with 1 equiv of
3
1
ppm in 9 and 10, respectively. The P NMR spectra showed
one singlet at ca. -9 ppm for PMe ligands in 4, 8, and 9, one
singlet at ca. 30 ppm for PPh ligands in 1, 2, 6, 7, and 10, one
2
2 10 10
NiCl (L) (L = PMe , n = 2; L = dppe, n = 1) in diethyl ether
2
3
n
3
at 0 °C in 83% and 45% isolated yields, respectively (Scheme 1).
To gain information on the effects of cage substituents on the
formation, structure, and stability of metal-carboryne com-
plexes, several B-substituted carboranes were selected as the
starting materials. Treatment of 9-I-1,2-C B H or 9,12-I2-
3
singlet at 63 ppm for the dppe ligand in 5, and satellite peaks
(1:5:1) at 19.7 ppm with a JP-Pt coupling constant of 1788 Hz
for 3.
Displacement of PPh
various phosphines were examined in order to gain information
on the lability of PPh ligands in 1. These reactions were closely
in 1. NMR reactions of 1 with
2
10 11
3
1
,2-C B H with 2 equiv of n-BuLi in THF at 0 °C, followed
2
10 10
by reaction with 1 equiv of NiCl (PPh ) at room temperature,
2
3
2
3 2
11
31
afforded (η -9-I-1,2-C B H )Ni(PPh ) (6) as a yellow solid in
monitored by B and P NMR spectra. The results showed
that the PPh ligands in 1can be completely substituted by dppe,
P(OEt)Ph , and P(OEt)
10)Ni(dppe) (5), (η -C
2
10
9
3 2
2
5
5% isolated yield or (η -9,12-I -1,2-C B H )Ni(PPh ) (7) as
3
2
2
10
8
3 2
2
yellow crystals in 72% isolated yield, respectively. No inter-
molecular interactions were observed between the Ni center and
the B-I unit of the second molecule (vide infra). Under the same
reaction conditions, reaction of 3-Br-1,2-Li -1,2-C B H with
2
at room temperature to give (η -
3
2
C B
2
H
B
H
10
10)Ni[P(OEt)Ph
(12), respectively. However,
the substitution reaction between 1 and 4 equiv of PCy was
10)Ni(PPh )-
in a molar ratio of
] (11),
10
2
2 2
2
and (η -C B H10)Ni[P(OEt) ]
2 10 3 2
2
2
10
9
3
2
1
carboryne complex; rather, 3-Br-1,2-C B H and Ni(0) spe-
equiv of NiCl (PPh ) did not produce the expected Ni-
not complete, giving a mixture of (η -C
2
B
H
10
3
2
3 2
2
(PCy ) (13) and (η -C B H10)Ni(PCy )
2
10 11
3 2 10 3 2
31
cies were generated probably due to the decomposition of the
Ni-carboryne at room temperature. However, if NiCl (PMe )
1:0.11 as measured by P NMR spectrum. X-ray-quality
crystals of 13 were obtained from the NMR solution, and its
molecular structure was characterized by X-ray analyses (vide
infra). The above reactions are outlined in Scheme 3. These
2
3 2
2
was used as the starting material, the expected complex (η -3-
Br-1,2-C B H )Ni(PMe ) (8) was isolated as yellow crystals in
2
10
9
3 2
31% isolated yield. These results suggested that steric factors
results indicated that the PPh ligands in 1 are very labile, which
3
play a role in the formation and stability of the Ni-carboryne
complexes, and the fewer steric interactions between 3-Br and
can be displaced by other Lewis bases. Steric factors play a role
14
in these substitution reactions. This is consistent with our early
observations that 1 cannot mediate the reaction of highly bulky
PMe moieties lead to the successful isolation of 8. In the case of
3
2
t
alkynes such as BuCtC Bu and TMSCtCTMS.
n
5
7
3
-Ph-1,2-C B H , both complexes (η -3-C H -1,2-C B H )-
2
10 11
6
5
2
10
9
2
Ni(PMe3)2 (9) and (η -3-C H -1,2-C B H )Ni(PPh ) (10)
Structure. The solid-state structures of 2-5 and 7-10 were
further confirmed by single-crystal X-ray analyses. A better
6
5
2
10
9
3 2
were isolated as yellow or orange crystals in 42% or 76%
isolated yields from an equimolar reaction of 3-C H -1,2-Li -
4
resolution of the molecular structure of 1 was also obtained
6
5
2
1
,2-C B H with NiCl (PMe ) or NiCl (PPh ) in THF
3 2
and is included in the discussion. Complexes 1-3 are iso-
structural, and their representative structure of 2 is shown in
Figure 1. Molecular structures of 4, 5, and 7-10 are shown in
Figures 2-7, respectively. As illustrated in the figures, the
2
10
9
2
3 2
2
(
Scheme 2).
Complexes 1-9 are sensitive to moisture and air, whereas
0 is air- and moisture-stable in both solid state and solution.
1
Complex 10 is also very thermally stable, and no decomposi-
tion is observed even after prolonged heating in THF.
However, complexes 1-9 decompose partially into neutral
(
14) Sun, Y.; Chan, H.-S.; Dixneuf, P. H.; Xie, Z. Organometallics
2004, 23, 5864.

Article
Organometallics, Vol. 29, No. 20, 2010 4543
2
Figure 2. Molecular structure of (η -C
2
B
10
H
10)Ni(PMe
3
)
2
(4).
2
Figure 1. Molecular structure of (η -C
2 10 3 2
B H10)Pd(PPh ) (2).
Scheme 3. Phosphine Exchange Reactions of 1
2
Figure 3. Molecular structure of (η -C B H )Ni(dppe) (5).
2
10 10
than group 10 metals to donate its d electrons to the π* orbital
1
6
of the carboryne ligand, resulting in much longer C(cage)-
C(cage) bond distances observed in Zr-carboryne com-
In other words, the interactions between the group 10
11,12
plexes.
metal atom and carboryne have more π character than those
observed in Zr-carboryne complexes.
˚
metal atom in all structures is bonded to two cage C atoms
and coordinated to two phosphorus atoms in an essentially
planar geometry. Selected bond distances and angles around
the metal atoms are listed in Table 1 for comparison.
The C(cage)-C(cage) bond distances (1.52-1.57 A) found in
all structures are generally shorter than those observed in the
The M-P distances are in the range 2.15-2.32 A (Table 1),
2
17
˚
which compare well with the 2.200(1) A in (η -C
H
)Ni(PCy
CH PCy
)Ni(PPh ) ,
3 2
) ,
6
4
3 2
2
18
˚
2.140(1) and 2.152(1) A in (η -C
H
)Ni(Cy
PCH
2.151(2) and 2.176(2) A in (η -PhCtCSiMe
),
2
6
4
2
2
2
2
19
˚
3
2
17
˚
˚
2.328(1) and 2.342(1) A in (η -C
H
)Pd(PCy
)
3
,
2.290(1) and
and 2.264(1) and
B(6)/B(3)
6
4
2
2
20
˚
2.281(1) A in (η -PhCtCPh)Pt(PPh ) ,
3 2
2 21
1
1,12
˚
˚
Zr-carboryne complexes (1.61-1.71 A)
and in o-carborane
2.271(1) A in (η -cyclohexyne)Pt(PPh
distances in 1-5 and 7-10 fall in the region 2.58-2.81 A. These
values are significantly longer than those observed in Ni (CO)
(2.261(11) A), 1,3,6-{Pd(dppe)}-
-2-Ph-closo-1,2-MnCB (2.257(5) and
) .
3 2
The M 3 3 3
˚
˚
(
1.63 A). The average Ni-C(cage) distances fall in the range
˚
1
.91-1.94 A. It is interesting to note that the shortest C(cage)-
2
-
2
5
22
˚
C(cage) distance of 1.523(3) A observed in 10 is associated with
˚
(η -2,7-Me
-2,7-C B H )
2 2 9 9 2
˚
the longest Ni-C(cage) distance of 1.937(2) A in 10, which is
consistent with that observed in metal-alkyne(alkene) π
3,6-(μ-H) -1,1,1-(CO)
2
3
H
9 7
15
complexes. This suggests some π interactions between the Ni
atom and carboryne unit in Ni-carboryne complexes. These
observations can be explained using a resonance hybrid bond-
ing mode of both the M-C σ- and M-C π-bonding forms
(16) Crabtree, R. H. The Organometallic Chemistry of the Transition
Metals; Wiley: NJ, 2005; Chapter 2, p 47.
(
17) Retbøll, M.; Edwards, A. J.; Rae, A. D.; Willis, A. C.; Bennett,
M. A.; Wenger, E. J. Am. Chem. Soc. 2002, 124, 8348.
18) Bennett, M. A.; Hambley, T. W.; Roberts, N. K.; Robertson,
(
(
Chart 1) proposed on the basis of DFT calculations on the
G. B. Organometallics 1985, 4, 1992.
(19) Bartlk, T.; Happ, B.; Iglewsky, M.; Bandmann, H.; Boese, R.;
Heimbach, P.; Hoffmann, T.; Wenschuh, E. Organometallics 1992, 11, 1235.
11
Zr-carboryne model complex. Zr(II) has a higher tendency
(
20) Harris, K. J.; Bernard, G. M.; McDonald, C.; McDonald, R.;
(
15) (a) Elschenbroich, C.; Salzer, A. Organometallics. A Concise
Ferguson, M. J.; Wasylishen, R. E. Inorg. Chem. 2006, 45, 2461.
(21) Robertson, G. B.; Whimp, P. O. J. Am. Chem. Soc. 1975, 97, 1051.
(22) Carr, N.; Mullica, D. F.; Sappenfield, E. L.; Stone, F. G. A.
Inorg. Chem. 1994, 33, 1666.
Introduction; VCH: New York, 1992; Chapter 15, p 256. (b) Jemmis, E. D.;
Roy, S.; Burlakov, V. V.; Jiao, H.; Klahn, M.; Hansen, S.; Rosenthal, U.
Organometallics 2010, 29, 76.

4
544 Organometallics, Vol. 29, No. 20, 2010
Qiu et al.
2
Figure 6. Molecular structure of (η -3-C H -1,2-C B H )Ni-
6
5
2
10
9
(
3 2
PMe ) (9).
2
Figure 4. Molecular structure of (η -9,12-I -1,2-C B H )Ni-
2
2
10
8
(
3 2
PPh ) (7).
2
Figure 5. Molecular structure of (η -3-Br-1,2-C
PPh ) (8).
2 10 9
B H )Ni-
2
Figure 7. Molecular structure of (η -3-C H -1,2-C B H )Ni-
6
5
2
10
9
(
3
2
(
PPh
3 2
) (10).
2
3
˚
2
1
.356(5) A), 3,6-{Pt(dppe)}-3,6-(μ-H) -1,1,1-(CO) -2-Ph-closo-
2 3
23
˚
solid-state IR spectra (KBr) exhibited only one very strong and
broad νB-H stretching band at about 2500 cm . These experi-
mental data suggest that there are very weak or no obvious
B-H M interactions in complexes 1-10. Therefore, they are
best described as 16e species. The relatively short M B dis-
tances observed in the above structures might also partially result
from crystal packing forces. It is noteworthy that as all B-H
hydrogen atoms are in calculated positions, a detailed discussion
of the B-H distances is not warranted.
,2-MnCB H (2.205(7) and 2.365(7) A), 1,3-{Pt(dppe)}-3-(μ-
9 7
24
H)-1,1,1-(CO) -2-Ph-closo-1,2-ReCB H (2.266(11) A), and
η -Me C B H )MoPt(CO) (PPh ) (2.313(8) A), in which
2 2 10 10 4 3
-1 27
˚
3
9 8
6
25
˚
(
the B-H M interactions have been identified. On the other
3 3 3
3
3 3
1
hand, neither a high-field signal in the H NMR spectra nor
3 3 3
significantly reduced J values or a very deshielded signal in
BH
the B NMR spectra was observed in complexes 1-10. The
11
26
(
23) Du, S.; Jeffery, J. C.; Kautz, J. A.; Lu, X. L.; McGrath, T. D.;
Miller, T. A.; Riis-Johannessen, T.; Stone, F. G. A. Inorg. Chem. 2005,
4, 2814.
24) Du, S.; Kautz, J. A.; McGrath, T. D.; Stone, F. G. A. Organo-
metallics 2003, 22, 2842.
25) Dossett, S. J.; Mullica, D. F.; Sappenfield, E. L.; Stone, F. G. A.;
Went, M. J. J. Chem. Soc., Dalton Trans. 1993, 281.
26) The B-H M interactions in late transition metal complexes
Conclusion
4
(
Salt metathesis between dilithiocarborane and metal
halides has proved to be a general method for the prepara-
tion of metal-carboryne complexes. A series of group 10
metal-carboryne complexes are thus synthesized and struc-
turally characterized. The phosphine ligands in these metal
complexes are labile and can be displaced by other Lewis
bases, which is important for their possible applications in
organometallic reactions. This work shows that the bonding
interactions between the transition metal and carboryne
have more π character in group 10 metal complexes than
group 4 metal ones probably due to a strong back-donation
(
(
3
3 3
1
1
usually lead to a significantly reduced JBH value, a very deshielded
B
1
signal, and a very high-field H resonance; see: (a) Brew, S. A.; Stone,
F. G. A. Adv. Organomet. Chem. 1993, 35, 135. (b) Franken, A.; McGrath,
T. D.; Stone, F. G. A. J. Am. Chem. Soc. 2006, 128, 16169. (c) McGrath,
T. D.; Du, S.; Hodson, B. E.; Lu, X. L.; Stone, F. G. A. Organometallics 2006,
5, 4444. (d) McGrath, T. D.; Du, S.; Hodson, B. E.; Stone, F. G. A.
Organometallics 2006, 25, 4452. (e) Hodson, B. E.; McGrath, T. D.; Stone,
F. G. A. Organometallics 2005, 24, 3386.
2
(
27) Crowther, D. J.; Borkowsky, S. L.; Swenson, D.; Meyer, T. Y.;
Jordan, R. F. Organometallics 1993, 12, 2897.

Article
Organometallics, Vol. 29, No. 20, 2010 4545
Table 1. Selected Bond Distances (A) and Angles (deg)
˚
compd (M)
C
cage-Ccage
av M-Ccage
M
3 3 B(3)
M
3 3 3 B(6)
av M-P
C
cage- M-Ccage
P-M-P
3
1
2
3
4
5
(Ni)
(Pd)
(Pt)
(Ni)
1.556(5)
1.564(5)
1.572(6)
1.576(4)
1.553(6)
1.561(5)]
1.550(6)
1.595(14)
1.565(5)
1.576(4)]
1.523(3)
1.551(4)
1.923(4)
2.085(4)
2.090(5)
1.913(3)
1.915(5)
[1.922(4)]
1.922(4)
1.918(6)
1.923(3)
[1.926(3)]
1.937(2)
1.931(3)
2.628(5)
2.780(5)
2.800(6)
2.622(7)
2.618(6)
[2.635(6)]
2.647(6)
2.628(5)
2.809(5)
2.810(6)
2.626(6)
2.616(6)
[2.632(5)]
2.626(6)
2.721(20)
2.631(4)
[2.583(4)]
2.581(3)
2.623(3)
2.195(1)
2.323(1)
2.283(2)
2.153(1)
2.160(1)
[2.155(1)]
2.202(1)
2.169(2)
2.168(1)
[2.164(1)]
2.218(1)
2.212(1)
47.7(2)
44.1(2)
44.2(2)
48.7(1)
47.8(2)
[47.9(2)]
47.6(2)
49.1(4)
48.1(1)
[48.3(1)]
46.3(1)
47.4(1)
108.9(1)
104.0(1)
102.6(1)
112.1(1)
89.8(1)
[89.8(1)]
110.0(1)
110.8(1)
104.4(1)
[107.5(1)]
111.7(1)
107.2(1)
a
(Ni)
[
[
7
8
9
(Ni)
(Ni)
(Ni)
a
1
1
0 (Ni)
3 (Ni)
2.680(3)
a
Numbers in brackets are those of a second molecule.
Chart 1. Bonding Interactions between Metal and Carboryne
of divalent group 4 metal species over group 10 metals. The
results also indicate that there are very weak or no obvious
B-H M interactions in group 10 metal-carboryne com-
3
3 3
plexes. Thus, they are best described as 16e species.
Experimental Section
General Procedures. All experiments were performed under
an atmosphere of dry dinitrogen with the rigid exclusion of air
and moisture using standard Schlenk or cannula techniques, or
in a glovebox. All organic solvents (except CH Cl ) were
2
2
refluxed over sodium benzophenone ketyl for several days and
freshly distilled prior to use. CH Cl was refluxed over CaH for
several days and distilled immediately before use. All chemicals
were purchased from either Aldrich or Acros Chemical Co. and
2
2
2
2
Figure 8. Molecular structure of (η -C B10H10)Ni(PPh )-
2
3
(PCy ) (13).
3
2
8
used as received unless otherwise noted. NiCl (PPh
2
3 2
) , 3-bromo-
29
30
o-carborane, 9-iodo-o-carborane, 9,12-diiodo-o-carborane,
and 3-phenyl-o-carborane were prepared according to literature
methods. Infrared spectra were obtained from KBr pellets pre-
pared in the glovebox on a Perkin-Elmer 1600 Fourier transform
spectrometer. H NMR spectra were recorded on either a Bruker
DPX 300 spectrometer at 300 MHz or a Bruker DPX 400 spectro-
meter at 400 MHz. C{ H} NMR spectra were recorded on
either a Bruker DPX 300 spectrometer at 75 MHz or a Bruker
31
2 2 10
resulting Li C B H10 suspension was then cooled to 0 °C, to
which was added NiCl (PPh ) (654 mg, 1.0 mmol). The reac-
tion mixture was then stirred for 0.5 h at room temperature,
giving a deep red solution. After removal of the solvent, the deep
brown residue was extracted with hot toluene (10 mL ꢀ 2). The
combined toluene solutions were concentrated to 10 mL. Com-
32
2
3 2
1
1
3
1
plex 1 was obtained as red crystals after this solution stood at
1
-
30 °C overnight (522 mg, 72%). H NMR (CD
2
Cl
2
): δ 7.36 (m,
Cl ): δ
= 45.3 Hz), 130.0,
C-P
1
1
DPX 400 spectrometer at 100 MHz. B NMR spectra were
recorded on either a Bruker DPX 300 spectrometer at 96 MHz
or a Bruker DPX 400 spectrometer at 128 MHz. All chemical
shifts were reported in δ units with references to the residual
solvent resonances of the deuterated solvents for proton and
13
1
6
1
1
H, C
6
H
5
), 7.26 (m, 24H, C
H
6 5
). C{ H} NMR (CD
2
2
2
33.2 (t, J
1
= 6.0 Hz), 131.3 (d, J
C-P
3
28.0 (t, JC-P = 4.8 Hz), the cage carbons were not observed.
B NMR (CD
11
2 2
Cl ): δ -3.9 (d, J = 153.6 Hz, 2B), -13.0 (d, J =
31
1
66.4 Hz, 4B), -15.1 (br, unresolved, 4B). P NMR (162 MHz,
carbon chemical shifts, to external BF
3
OEt
boron chemical shifts, and to external 85% H
2
(0.00 ppm) for
PO (0.00 ppm)
-1
3
CD Cl ): δ 33.3. IR (KBr, cm ): ν 2559 (vs). This is a known
2 2 BH
4
3
4
complex, but no NMR data were reported.
for phosphorus chemical shifts. Elemental analyses were
performed by the Shanghai Institute of Organic Chemistry,
CAS, China.
2
Preparation of (η -C
of n-BuLi in n-hexane (1.30 mL, 2.1 mmol) was slowly added to a
stirring solution of o-C 12 (144 mg, 1.0 mmol) in diethyl
ether (20 mL) at 0 °C, and the mixture was stirred at room
temperature for 1 h. The resulting Li 10 suspension was
then cooled to 0 °C, and PdCl (PPh ) (700 mg, 1.0 mmol) was
2 10 3 2
B H10)Pd(PPh ) (2). A 1.6 M solution
2 10
B H
2
Preparation of (η -C
2
B
10
H
10)Ni(PPh
3
)
2
(1). A modified pro-
cedure was used. A 1.6 M solution of n-BuLi in n-hexane (1.30
4
2 2 10
C B H
mL, 2.1 mmol) was slowly added to a stirring solution of
o-C B H12 (144 mg, 1.0 mmol) in THF (10 mL) at 0 °C, and
2 10
the mixture was stirred at room temperature for 1 h. The
2
3 2
added. The reaction mixture was then stirred for 0.5 h at room
temperature, giving a yellow suspension. After filtration, the
residue was further extracted with diethyl ether (10 mL ꢀ 2). The
diethyl ether solutions were combined and concentrated to
20 mL. Complex 2 was obtained as yellow crystals after this
solution stood at room temperature overnight (464 mg, 60%).
(28) Venanzi, L. M. J. Inorg. Nucl. Chem. 1958, 8, 137.
(29) Li, J.; Jones, M., Jr. Inorg. Chem. 1990, 29, 4162.
(30) Andrew, J. S.; Zayas, J.; Jones, M., Jr. Inorg. Chem. 1985, 24,
3
715.
31) Barber
n~ as, C. Inorg. Chem. 2008, 47, 7309.
32) Ohta, K.; Goto, T.; Endo, Y. Inorg. Chem. 2005, 44, 8569.
1
H NMR (CD Cl ): δ 7.35 (m, 6H, C H ), 7.21 (m, 24H, C H ).
ꢀ
a, G.; Vaca, A.; Teixidor, F.; Sillanp €a €a , R.; Kivek €a s, R.;
2
2
6
2
5
6
5
(
1
1
3
1
C{ H} NMR (CD
2 2
Cl ): δ 133.3 (t, JC-P = 6.8 Hz), 131.6 (d,
3
JC-P = 42.9 Hz), 130.1, 128.2 (t, JC-P = 5.1 Hz), the cage
Vi
(

4
546 Organometallics, Vol. 29, No. 20, 2010
Table 2. Crystal Data and Summary of Data Collection and Refinement for 1-5
Qiu et al.
1
2
3
4
5
formula
fw
space group
C
725.45
P2 /n
14.767(3)
16.511(3)
16.039(3)
90
92.85(3)
90
3906(1)
4
1.234
0.71073
0.606
0.049
38
H
40
B
10NiP
2
C
773.14
P(-1)
38
H
40
B
10PdP
2
C
861.83
P(-1)
38
H
40
B
10PtP
2
C
353.05
Pnma
11.306(2)
15.471(2)
11.253(2)
90
90
90
8
H
28
B
10NiP
2
28 34 2
C H B10NiP
599.30
P(-1)
1
˚
a, A
11.561(1)
11.766(1)
16.043(1)
111.35(1)
98.55(1)
102.89(1)
1916.6(3)
2
11.538(1)
11.733(1)
16.028(1)
68.574(1)
71.865(1)
77.144(1)
1905.0(1)
2
11.812(1)
15.698(2)
17.794(2)
89.94(1)
84.81(1)
74.48(1)
3165.1(7)
4
˚
b, A
˚
c, A
R, deg
β, deg
γ, deg
3
˚
V, A
Z
1968.2(5)
4
3
Dcalcd, Mg/m
1.340
1.502
1.191
0.71073
1.131
0.043
0.098
1.258
˚
radiation (λ), A
0.71073
0.596
0.048
0.71073
3.795
0.032
0.71073
0.733
0.061
-1
μ, mm
R1
wR2
a
a
0.117
0.113
0.077
0.124
P
P
P
P
a
2
2 2
2 2 1/2
) ]]
R1 =
F
o
| - |F
c
/
|F
o
|; wR2 = [ [w(F
o
- F
c
) ]/ [w(F
o
.
Table 3. Crystal Data and Summary of Data Collection and Refinement for 7-10 and 13
7
8
9
10
10NiP
801.54
P2 /n
12.958(1)
21.107(1)
15.398(1)
90
92.682(1)
90
4188.9(4)
4
1.271
0.71073
0.572
0.031
13
formula
fw
space group
C
38
H
38
977.23
B
10
I
2
NiP
2
C
431.96
Ama2
8
H
27
B
10BrNiP
2
C
14
H
32
B
10NiP
2
C
44
H
44
B
2
38 58 2
C H B10NiP
743.59
P2 /n
18.276(3)
11.582(2)
20.716(3)
90
108.34(1)
90
4162.5(30)
4
1.187
0.71073
0.126
0.048
429.15
P2
8.937(1)
15.886(1)
17.545(2)
90
104.205(2)
90
2414.9(4)
4
1.180
P(-1)
1
1
1
˚
a, A
12.597(2)
12.615(2)
14.992(2)
71.936(3)
78.406(3)
71.484(2)
2133.9(5)
2
15.253(2)
11.484(2)
11.858(2)
90
˚
b, A
˚
c, A
R, deg
β, deg
γ, deg
90
90
3
˚
V, A
Z
2077.0(5)
4
3
Dcalcd, Mg/m
1.521
1.381
0.71073
2.998
0.055
0.149
˚
radiation (λ), A
0.71073
2.004
0.041
0.71073
0.934
0.033
-1
μ, mm
R1
wR2
a
a
0.098
0.084
0.081
0.089
P
P
P
P
a
2
2 2
2 2 1/2
) ]]
R1 =
F
o
| - |F
c
/
|F
o
|; wR2 = [ [w(F
o
- F
c
) ]/ [w(F
o
.
1
carbons were not observed. B NMR (CD
1
2
Cl
2
): δ -3.9 (d, J =
for C
H, 7.68.
Preparation of (η -C
2 2 10
prepared as red crystals from Li C B H
8
H
28
B
2
10NiP (4): C, 27.22; H, 7.99. Found: C, 27.69;
1
36.7 Hz, 2B), -12.2 (br, unresolved, 1B), -14.2 (d, J = 146.2
31
2
Hz, 3B), -15.6 (d, J = 174.5 Hz, 4B). P NMR (162 MHz,
2
B
10
H10)Ni(dppe) (5). This complex was
-
1
CD
complex, but no NMR data were reported.
2
Cl
2
): δ 30.5. IR (KBr, cm ): νBH 2566 (vs). This is a known
10 (1.0 mmol) and
13a
NiCl (dppe) (526 mg, 1.0 mmol) in diethyl ether (30 mL) using
2
2
1
the same procedure reported for 2: yield 269 mg (45%). H
Preparation of (η -C B H )Pt(PPh ) (3). This complex was
2
10 10
3 2
prepared as yellow crystals from Li
o-C 12 (144 mg, 1.0 mmol) and n-BuLi (1.30 mL, 2.1 mmol,
.6 M in hexane)] and PtCl (PPh ) (789 mg, 1.0 mmol) in diethyl
2
C
2
B
10
H
10 [prepared in situ from
NMR (benzene-d
6
): δ 7.56 (m, 8H, C
6
H
5
), 6.93 (m, 12H, C
). C{ H} NMR (benzene-d ): δ 133.0 (d,
= 11.2 Hz), 131.2 (d, J = 42.4 Hz), 130.5, 129.7 (d,
C-P C-P
6 5
H ),
1
3
1
2 10
B H
1.76 (m, 4H, CH
2
6
2
1
1
J
J
2
3 2
3
1
ether (30 mL) using the same procedure reported for 2: yield 586 mg
68%). X-ray-quality crystals of 3 were grown from a saturated
C-P = 10.0 Hz) (PC
6
H
5
), 26.8 (d, JC-P = 38.0 Hz) (PCH
2
),
1
1
(
THF solution at room temperature. H NMR (CD
the cage carbons were not observed. B NMR (benzene-d
6
): δ
1
2
Cl
2
): δ 7.48 (m,
-1.4 (d, J = 112.6 Hz, 2B), -9.9 (d, J = 124.2 Hz, 2B), -13.0
13
1
2H, C H ), 7.23 (m, 18H, C H ). C{ H} NMR (CD Cl ):
31
1
(br, unresolved, 6B). P NMR (benzene-d ): δ 63.00. IR (KBr,
6
5
6
5
2
2
6
2
1
-1
δ 133.5 (d, JC-P =12.8 Hz), 131.5 (d, JC-P=54.9 Hz), 130.5,
cm ): νBH 2553 (vs). Anal. Calcd for C28
56.12; H, 5.72. Found: C, 56.48; H, 5.86.
H
34
B
10NiP
2
(5): C,
3
11
B
1
28.2 (d, JC-P=9.2 Hz), the cage carbons were not observed.
NMR (CD Cl ): δ -3.2 (d, J = 146 Hz, 3B), -9.6 (br, unresolved,
B), -14.6 (d, J = 139 Hz, 3B). P NMR (CD Cl ): δ 19.73
2
2
2
Preparation of (η -9-I-1,2-C
plex was prepared from 1,2-Li -9-I-C B H (prepared in situ
2 2 10 9
B
2 10
H
9
)Ni(PPh
3
)
2
(6). This com-
3
1
4
2
2
-
1
(
J
P-Pt = 1788 Hz). IR (KBr, cm ): νBH 2557 (vs). This is a known
from 9-I-1,2-C
2
B
10
H11 (135 mg, 0.5 mmol) and n-BuLi (0.63 mL,
1
3a
complex, but no NMR data were reported.
1.0 mmol, 1.6 M in hexane)) and NiCl (PPh (327 mg, 0.5 mmol)
2
3 2
)
2
Preparation of (η -C B H )Ni(PMe ) (4). This complex
in THF (10 mL) using the same procedure reported for 1. Recrys-
tallization from toluene gave 6 0.5toluene as a yellow solid after the
2
10 10
3 2
was prepared as yellow crystals from Li C B H [prepared
2
2
10 10
3
1
solution stood at room temperature for 2 days (247 mg, 55%). H
in situ from o-C
mL, 2.1 mmol, 1.6 M in hexane)] and NiCl
.0 mmol) in diethyl ether (20 mL), using the same procedure
2
B
10
H
12 (144 mg, 1.0 mmol) and n-BuLi (1.30
2
(PMe (282 mg,
3
)
2
6 6 5
NMR (benzene-d ): δ 7.28 (m, 24H, PC H ), 7.11 (m, 3H, toluene),
1
7.02 (m, 2H, toluene), 6.86 (m, 36H, PC H ), 2.10 (s, 3H, toluene).
6
2
5
1
13
1
reported for 2: yield 293 mg (83%). H NMR (CD
2
Cl
Cl
d, JC-P = 28.4 Hz), the cage carbons were not observed.
2
): δ 1.34
C{ H} NMR (benzene-d
6
): δ 133.7 (d, JC-P = 11.5 Hz, PC
131.9 (d, JC-P=44.5 Hz, PC ), 130.6 (PC ), 129.3 (toluene),
6 5
128.7 (d, JC-P=6.1 Hz, PC H ), 128.6 (toluene), 125.7 (toluene),
6 5
H ),
1
3
1
1
(
(
s, 9H), 1.32 (s, 9H) (PCH
3
). C{ H} NMR (CD
2
2
): δ 16.7
6
H
5
6 5
H
1
11
3
B
11
NMR (CD Cl ): δ -4.1 (d, J = 140.0 Hz, 2B), -12.5 (d, J =
the cage carbons were not observed. B NMR (benzene-d ): δ -1.1
2
2
6
3
1
1
41.6 Hz, 2B), -15.5 (d, J = 156.7 Hz, 6B). P NMR
(br, unresolved, 3B), -13.9 (br, unresolved, 6B), -22.9(s, 1B) (B-I).
): δ -6.8. IR (KBr, cm- ): νBH 2550 (vs). Anal. Calcd
1
31
-1
(
CD
2
Cl
2
6
P NMR (benzene-d ): δ 33.9. IR (KBr, cm ): νBH 2578 (vs).

Article
Organometallics, Vol. 29, No. 20, 2010 4547
Anal. Calcd for C83
4.83. Found: C, 55.68; H, 5.06.
H
86
B
20Ni
2
P
4
I
2
(6þ0.5toluene): C, 55.54; H,
7.18 (m, 14H, BC
6
H
5
and PC
): δ 135.3, 134.0 (m, JC-P unresolved),
= 44.2 Hz), 130.5, 128.6 (m, J unresolved),
6 5 6 5
H ), 7.06 (m, 12H, PC H ).
1
3
1
2 2
C{ H} NMR (CD Cl
2
1
Preparation of (η -9,12-I -1,2-C B H )Ni(PPh ) (7). A 1.6
131.9 (d, J
C-P
2
2
10
8
3 2
C-P
1
1
M solution of n-BuLi in n-hexane (0.63 mL, 1.0 mmol) was
slowly added to a stirring solution of 9,12-I -1,2-C H10 (198
2 2
128.1, the cage carbons were not observed. B NMR (CD Cl ):
2
2
B
10
δ -0.8 (s, 1B) (B-Ph), -1.0 (d, J = 124.8 Hz, 1B), -7.7 (d, J =
132.8 Hz, 1B), -11.9 (d, J = 124.8 Hz, 3B), -13.4 (d, J = 153.6
mg, 0.5 mmol) in THF (10 mL) at 0 °C, and the mixture was
3
1
-1
stirred at room temperature for 1 h. The resulting 1,2-Li -9,12-
I
Hz, 4B). P NMR (CD Cl ): δ 29.6. IR (KBr, cm ): ν 2557
2
2
2
BH
2
-1,2-C
2
B
10
H
8
suspension was then cooled to 0 °C, and NiCl
(327 mg, 0.5 mmol) was added. The reaction mixture
2
-
(vs). Anal. Calcd for C44
Found: C, 66.12; H, 5.54.
H
44
B10NiP
2
(10): C, 65.93; H, 5.53.
(
PPh
3
)
2
was then stirred for 0.5 h at room temperature, giving a brown
solution. After removal of the solvent, the deep brown residue
was extracted with CH Cl (20 mL). The brown filtrate was
2 2
Reactions of 1 with Phosphines. An NMR tube was loaded
with 1 (25 mg, 0.035 mmol) and THF (0.5 mL). Phosphine (0.138
mmol) was then added to the NMR tube at room temperature in a
11
31
concentrated to 3 mL. Complex 7 was obtained as yellow
crystals after this solution stood at -30 °C overnight (352 mg,
glovebox. These reactions were monitored by B and P NMR
spectra at room temperature. P NMR spectra indicated the quan-
31
1
2%). H NMR (CD
2
2
7
2
Cl
2
): δ 7.40 (m, 6H, C
6
H
5
), 7.25 (m, 24H,
titative formation of (η -C
2
B
10
H
10)Ni(dppe) (5), (η -C
10)Ni[P(OEt) (12) after one
) (13) was observed as a major
2 10
B H10)Ni-
1
3
1
). C{ H} NMR (CD
2
2
C
H
6 5
Cl
2 2
): δ 133.1 (t, JC-P = 6.0 Hz),
[P(OEt)Ph
hour. (η -C
2
]
2
(11), and (η -C
2
B
10
H
3 2
]
1
3
2
1
31.8 (d, JC-P = 37.1 Hz), 130.3, 128.2 (t, JC-P = 4.9 Hz), the
2
B
10
H
10)Ni(PPh )(PCy
3
3
1
1
11
cage carbons were not observed. B NMR (CD Cl ): δ -0.5 (d,
product. For 11: B NMR (THF): δ -2.8 (2B), -11.2 (2B), -14.1
2
2
31 11
J = 140.8 Hz, 2B), -14.0 (br, unresolved, 6B), -21.6 (s, 2B)
(6B). P NMR (THF): δ 134.6. For 12: B NMR (THF): δ -2.8
31
-1
31
(
(
B-I). P NMR (CD
vs). Anal. Calcd for C H B NiP I (7): C, 46.70; H, 3.92.
2
Cl
2
): δ 32.4. IR (KBr, cm ): νBH 2592
(2B), -10.6 (2B), -13.5 (4B), -15.0 (2B). P NMR (THF): δ
11
160.1. For 13: B NMR (THF): δ -2.8 (2B), -11.6 (2B), -13.4
3
8
38 10
2 2
31
Found: C, 47.19; H, 3.97.
(4B), -14.2 (2B). P NMR (THF): δ 42.90 (1P), 31.18 (1P).
X-ray Structure Determination. All single crystals were
immersed in Paraton-N oil and sealed under nitrogen in
thin-walled glass capillaries. Data were collected at 293 K
on a Bruker SMART 1000 CCD diffractometer using Mo KR
2
Preparation of (η -3-Br-1,2-C
complex was prepared from 1,2-Li
2
B
10
H
-3-Br-C
9
)Ni(PMe
B
10
3
)
2
(8). This
(prepared
2
2
H
9
in situ from 3-Br-1,2-C B H (112 mg, 0.5 mmol) and n-BuLi
2
10 11
(
2 3 2
0.63 mL, 1.0 mmol, 1.6 M in hexane)) and NiCl (PMe ) (141
˚
mg, 0.5 mmol) in THF (10 mL), using the same procedure
reported for 1. Complex 8 was obtained as yellow crystals after
the solution stood at room temperature for 2 days (67 mg, 31%).
radiation (0.71073 A). An empirical absorption correction
3
3
was applied using the SADABS program. All structures
were solved by direct methods and subsequent Fourier dif-
ference techniques and refined anisotropically for all non-
hydrogen atoms by full-matrix least-squares on F using the
SHELXTL program package. For the non-centrosym-
metric structures, the appropriate enantiomorph was chosen
1
13
1
H NMR (benzene-d ): δ 0.73 (br, 18H, CH ). C{ H} NMR
6 3
1
1
2
(
benzene-d
6
): δ 16.7 (t, JC-P = 14.0 Hz), 16.4 (t, JC-P = 13.0
Hz), the cage carbons were not observed. B NMR (ben-
1
1
34
zene-d ): δ -1.5 (d, J = 144.6 Hz, 1B), -8.4 (d, J = 147.6 Hz,
6
3
5
1
B), -10.8 (d, J = 159.7 Hz, 3B), -11.6 (s, 1B) (B-Br), -12.6
by refining Flack’s parameter x toward zero. All hydrogen
atoms were geometrically fixed using the riding model, so that
a detailed discussion of the B-H distances was not warranted.
Crystal data and details of data collection and structure
refinements are given in Tables 2 and 3, respectively. Further
details were included in the Supporting Information.
31
(
(
br, unresolved, 2B), -14.1 (d, J = 173.6 Hz, 2B). P NMR
-1
benzene-d ): δ -9.4. IR (KBr, cm ): ν
2551 (vs). Anal.
(8): C, 22.25; H, 6.30. Found: C,
6
BH
Calcd for C
2
H
8 27
B
10BrNiP
2
2.61; H, 6.18.
2
Preparation of (η -3-C
complex was prepared from 1,2-Li -3-C H -C B H (prepared
6
H
5
-1,2-C )Ni(PMe (9). This
2
B
10
H
9
3 2
)
2
6
5
2
10
9
in situ from 3-C
n-BuLi (0.63 mL, 1.0 mmol, 1.6 M in hexane)) and NiCl
PMe (141 mg, 0.5 mmol) in THF (10 mL), using the same
procedure reported for 1. Complex 9 was obtained as yellow
crystals after the solution stood at room temperature for 3 days
6
H
5
-1,2-C
2
B
10
H
11 (110 mg, 0.5 mmol) and
Acknowledgment. This work was supported by grants
from the Research Grants Council of the Hong Kong SAR
2
-
(
3 2
)
(Project No. 404108), The Chinese University of Hong
Kong, and State Key Laboratory of Elemento-Organic
Chemistry, Nankai University (Project No. 0314).
1
90 mg, 42%). H NMR (CD
(
(
2
Cl
2
): δ 7.82 (m, 2H, C
3
6
H
5
), 7.30
1
3
1
m, 3H, C H ), 1.16 (br, 18H, CH ). C{ H} NMR (CD Cl ): δ
6
5
2
2
1
33.6, 127.6, 126.9 (C H ), 16.5 (t, J
Note Added after ASAP Publication. In the version of this
paper published on Sep 23, 2010, the designation of group 8 was
incorrectly given in the title, abstract, and text. The correct
designation of group 10 now appears in the version published on
Oct 1, 2010.
1
= 15.6 Hz), 16.2 (t,
6
5
C-P
1
J
3
C-P = 14.4 Hz) (PCH ), the cage carbons were not observed.
1
1
2 2
B NMR (CD Cl ): δ -2.8 (d, J = 144.6 Hz, 1B), -3.8 (s, 1B)
(
B-Ph), -8.2 (d, J = 137.1 Hz, 1B), -12.2 (d, J = 143.1 Hz, 2B),
3
15.2 (d, J = 146.0 Hz, 5B). P NMR (CD
(KBr, cm ): νBH 2550 (vs). Anal. Calcd for C14
C, 39.18; H, 7.52. Found: C, 38.96; H, 7.71.
1
-
2
Cl
H
32
2
): δ -9.1. IR
10NiP (9):
-
1
B
2
Supporting Information Available: Crystallographic data in
CIF format for 1-5, 7-10, and 13. This material is available free
of charge via the Internet at http://pubs.acs.org.
2
Preparation of (η -3-C H -1,2-C B H )Ni(PPh ) (10). This
6
5
2
10
9
3 2
complex was prepared from 1,2-Li
prepared in situ from 3-C -1,2-C
and n-BuLi (0.63 mL, 1.0 mmol, 1.6 M in hexane)) and NiCl2-
PPh ) (327 mg, 0.5 mmol) in THF (10 mL), using the same
2
-3-C
6
5
H -1,2-C
2 10 9
B H
(
6
H
5
2 10
B H11 (110 mg, 0.5 mmol)
(33) Sheldrick, G. M. SADABS: Program for Empirical Absorption
Correction of Area Detector Data; University of G €o ttingen: Germany,
(
3
2
1
996.
34) Sheldrick, G. M. SHELXTL 5.10 for Windows NT: Structure
procedure reported for 1. Complex 10 was obtained as orange
crystals after the solution stood at room temperature for 3 days
(
Determination Software Programs; Bruker Analytical X-ray Systems, Inc.:
Madison, WI, USA, 1997.
(35) Flack, H. D. Acta Crystallogr. 1983, A39, 876.
1
(
BC
305 mg, 76%). H NMR (CD Cl ): δ 7.70 (d, J = 7.2 Hz, 2H,
2
2
6
H
5
), 7.45 (t, J = 7.2 Hz, 1H, BC
6
5
H ), 7.33 (m, 6H, PC
6
5
H ),