Synthesis and structural characterisation of novel nickelaindenyl and nickelafluorenyl compounds: Differences in the bonding modes of nickelacyclic rings

Article abstract of DOI:10.1016/j.jorganchem.2006.06.013

New binuclear nickelacyclic compounds 1 (η⁵-pentamethylcyclopentadienyl)(η³-(1-(η⁵-pentamethylcyclopentadienyl))-1-nickelafluorenyl)nickel and 2 (η⁵-pentamethylcyclopentadienyl)(η³-(1-(η⁵-p

Full text of DOI:10.1016/j.jorganchem.2006.06.013

Journal of Organometallic Chemistry 691 (2006) 4080–4085
www.elsevier.com/locate/jorganchem
Synthesis and structural characterisation of novel nickelaindenyl
and nickelafluorenyl compounds: Differences in the bonding modes
of nickelacyclic rings
a,
a
a
a
Piotr Buchalski *, Andrzej Kozioł , Stanisław Pasynkiewicz , Antoni Pietrzykowski ,
b
a
´
Kinga Suwinska , Monika Zdziemborska
a
Warsaw University of Technology, Faculty of Chemistry, Koszykowa 75, 00-662 Warsaw, Poland
Institute of Physical Chemistry of the Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
b
Received 13 March 2006; received in revised form 17 May 2006; accepted 9 June 2006
Available online 20 June 2006
Abstract
New binuclear nickelacyclic compounds 1 (g5-pentamethylcyclopentadienyl)(g3-(1-(g5-pentamethylcyclopentadienyl))-1-nickelafluor-
enyl)nickel and 2 (g5-pentamethylcyclopentadienyl)(g3-(1-(g5-pentamethylcyclopentadienyl))-2-phenyl-3-ethyl-1-nickelaindenyl)nickel
were synthesised in reactions of dilithioorganic compounds with Cp*Ni(acac) and characterised by high resolution mass spectrometry,
magnetic moment determination and X-ray single crystal analysis. The bonding mode of the central nickel atom to the nickelaindenyl
and nickelafluorenyl ligands was not g5 like in the previously described analogues of nickelocene but half way between g3 and g5.
ꢀ 2006 Elsevier B.V. All rights reserved.
Keywords: Nickel; Organolithium compounds; Clusters; Cyclopentadienyl; Metallacyclic compounds
1. Introduction
bridization of the indenyl p-system which increased the
aromatic character of the benzene ring but also disrupted
the aromatic character of the five-membered ring [4a]
The well known structure of nickelocene reveals that
both cyclopentadienyl rings are flat and parallel to each
other [1], and they are bonded to the nickel atom in g5
manner. It is still the same in derivatives of nickelocene
in which one or both rings are substituted by various
ligands [2] no matter if the nickelocene molecule is neutral
or cationic [3]. The exceptions are indenyl [4] and indacenyl
[5] complexes, in which the slippage of the ring occurs and
the coordination mode of the nickel atom changes from g5
to g3. The consequence of it is also that the five-membered
rings in these compounds are not flat. Taylor and Marder
suggested that the relative ease of the ring slippage for
indenyl complexes should had been attributed to the rehy-
Such disruption would be a higher energy process for
cyclopentadienyl ligands therefore in the cyclopentadienyl
complexes the rings are flat and bonded to nickel atom in
g5 manner
*
We have recently described the synthesis of analogues of
nickelocene possessing nickelaindenyl ring [6]. In these
Corresponding author. Tel.: +48 22 660 7859; fax: +48 22 660 5462.
E-mail address: pjb@ch.pw.edu.pl (P. Buchalski).
0022-328X/$ - see front matter ꢀ 2006 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2006.06.013

P. Buchalski et al. / Journal of Organometallic Chemistry 691 (2006) 4080–4085
4081
compounds the X-ray studies proved that the central nickel
atom was bonded to the cyclopentadienyl ring and to the
flat, metalated indenyl ring. The bonding mode of the
nickel atom to the nickelaindenyl ring was g5. Such struc-
ture is quite different from the structures of the known
indenyl nickel complexes where the ring is bent and g3
bonded to the central nickel atom [4]
CpNi
R
R = Me, Et
Ph
Ni
Cp
In this work we present synthesis and structure of two
new compounds, derivatives of decamethylnickelocene,
with nickelaindenyl and nickelafluorenyl rings. The influ-
ence of pentamethylcyclopentadienyl ligands on the bond-
ing mode of the central nickel atom to the nickelacyclic
rings is shown.
2. Results
Fig. 1. ORTEP view of the molecular structure of 1 showing the atom
numbering scheme. Thermal ellipsoids drawn at 30% probability level.
Hydrogen atoms were omitted for the clarity.
Pentamethylcyclopentadienylnickelacetylacetonate was
reacted with 2,20-dilithiobiphenyl in diethyl ether at
ꢀ30 ꢁC for 1 h and then at room temperature overnight.
The reaction mixture was chromatographed on neutral alu-
mina deactivated with 5% of water. Only one red-brown
fraction was collected which after evaporation of solvents
gave brown solid characterised as 1 (yield 96%)
˚
uated in one plane while nickel atom is deviated by 0.378 A
˚
(molecule A) and 0.492 A (molecule B) from this plane.
The hinge angle, defined as the dihedral angle between
the planes C1–C6–C6–C1 and C1–Ni1–C1 is 15.4ꢁ in mol-
ecule A and 20.0ꢁ in molecule B. The central nickel atom
(Ni2) is bonded to the pentamethylcyclopentadienyl ring
and the nickelacyclic ring. To define a bonding mode of
the central nickel atom (Ni2) to the nickelafluorenyl ring,
we have determined the degree of slip-fold distortion, using
parameters as described in [4a]. The slip parameter defined
Cp*Ni
Et2O
+ 2Cp*Ni(acac)
Ni
Cp*
Li Li
˚
as DM–C = avgd(Ni2–C1) ꢀ avgd(Ni2–C6) is 0.253 A in
1
˚
molecule A and 0.324 A in molecule B. These values show
that the coordination mode of the nickelacyclic ring to the
EIMS spectrum of 1 showed the parent ion at m/e 538
nickel atom (Ni2) is in between g3 and g5.
(58Ni calc.) with an isotopic pattern characteristic for two
1
The compound 2 was synthesised in the reaction of pen-
tamethylcyclopentadienylnickelacetylacetonate with (E)-1-
lithio-1-phenyl-2-(2-lithiophenyl)ethane in diethyl ether at
ꢀ30 ꢁC for 1 h and then at room temperature overnight.
The reaction mixture was chromatographed on neutral alu-
mina deactivated with 5% of water. One brown fraction
was collected which after evaporation of solvents gave
brown solid characterised as 2 (isolated yield 16%)
nickel atoms in the molecule. H NMR (C6D6) spectrum
of 1 revealed four broad signals at 19 ppm, 11 ppm,
ꢀ82 ppm and ꢀ108 ppm. Magnetic moment of 1 in toluene
solution at 295 K is 2.786 lB, what indicates that the com-
pound is paramagnetic with two unpaired electrons per
molecule. There were no signals in EPR spectrum of 1 nei-
ther at room temperature nor at 77 K, neither in solid state
nor in benzene solution.
Crystals of 1 appropriate for X-ray diffraction studies
were grown from hexane solution. The molecular structure
of 1 is presented in Fig. 1. Selected bond lengths and angles
are shown in Table 2. Crystal data, data collection and
refinement parameters are given in Table 1. The compound
crystallises in orthorhombic crystal system. There are two
independent molecules (A and B) in an asymmetric unit
Cp*Ni
Et
Et
Et2O
+ 2 Cp*Ni(acac)
Ph
Ph
Ni
Cp*
Li Li
2
˚
cell. The Ni–Ni bond (2.4 A) is within the range of
EIMS spectrum of 2 showed the parent ion at m/e 592
(58Ni calc.) with an isotopic pattern characteristic for two
nickel–nickel single bonds. Carbon atoms (C1, C1, C6,
C6) and nickel atom (Ni1) form a five-membered heterocy-
clic ring. This ring is not planar. Four carbon atoms are sit-
1
nickel atoms in a molecule. H NMR (C6D6) spectrum of
2 revealed seven broad signals at 14 ppm, 13 ppm, 8 ppm,

4082
P. Buchalski et al. / Journal of Organometallic Chemistry 691 (2006) 4080–4085
Table 1
Crystal data and structure refinement parameters for 1 and 2
1
2
Empirical formula
Crystal size (mm)
Crystal system
C32H38Ni2
C36H44Ni2
0.4 · 0.3 · 0.3
Monoclinic
P21/c
0.4 · 0.3 · 0.2
Orthorhombic
Pnma
Space group
Unit cell dimensions
˚
a (A)
21.3622(2)
16.3400(2)
15.6996(3)
90
90
90
17.2540(5)
17.0855(5)
20.1488(6)
90
97.983(2)
90
˚
b (A)
˚
c (A)
a (ꢁ)
b (ꢁ)
c (ꢁ)
3
˚
Volume (A )
5480(1)
8
5882(4)
8
Z
Formula weight
Density (calculated) (Mg mꢀ3
Temperature (K)
Absorption coefficient (mmꢀ1
F(000)
540.03
1.291
294(2)
1.391
2228
594.13
1.342
150(2)
1.303
)
)
2528
˚
Radiation
Mo Ka (k = 0.71073 A, graphite monochromator)
h Range for data collection (ꢁ)
Scan type
2.97–27.49
x–2h
2.91–27.51
x–2h
Index ranges
ꢀ27 6 h 6 27,
ꢀ21 6 k 6 21,
ꢀ20 6 l 6 20
43,084/6493 (0.0280)
Full-matrix least-squares on F2
6493/0/357
ꢀ22 6 h 6 22,
ꢀ22 6 k 6 20,
ꢀ26 6 l 6 26
36,054/13,442 (0.0671)
Reflections collected/unique (Rint
Refinement method
Data/restraints/parameters
Goodness-of-fit on F2
)
13,442/0/708
0.950
1.030
Final R indices [I > 2r(I)]
P
P
R1 = (Fo ꢀ Fc)/ Fo
R1 = 0.0461
wR2 (refined) = 0.1171
R1 = 0.0530
wR2 (refined) = 0.0944
wꢀ1 ¼ r2ðF 2oÞ þ ð0:0463PÞ þ 0:0000P
P
P
2
2
1=2
wR2 ¼ f ½wðF 2o ꢀ F c2Þ ꢁ= ½wðF 2oÞ ꢁg
2
2
Weighting scheme
wꢀ1 ¼ r2ðF 2oÞ þ ð0:0668PÞ þ 2:7186P
where P ¼ ðF 2o þ 2F c2Þ=3
R1 = 0.0710; wR2 = 0.1259
0.486 and ꢀ0.342
R indices (all data)
Largest difference in peak and hole (e A
R1 = 0.1323; wR2 = 0.1163
0.639 and ꢀ0.656
ꢀ3
˚
)
Table 2
Crystals of 2 appropriate for X-ray diffraction studies
were grown from hexane solution. The molecular structure
of 2 is presented in Fig. 2. Selected bond lengths and angles
are shown in Table 3. Crystal data, data collection and
refinement parameters are given in Table 1. The compound
crystallises in monoclinic crystal system. There are two
independent molecules (A and B) in the unit cell. The
˚
Selected interatomic distances (A) and angles (ꢁ) for 1
Molecule A
Molecule B
Ni1–Ni2
Ni1–C1
C1–C6
C6–C6
Ni2–C1
Ni2–C6
2.4003(7)
1.922(3)
1.421(4)
1.464(6)
2.162(3)
2.415(3)
2.391(1)
1.932(3)
1.416(4)
1.460(6)
2.162(3)
2.486(3)
˚
Ni–Ni bond is long (2.48 A) but still in the range of
nickel–nickel single bonds [7]. Four carbon atoms (C1,
C6, C7, C8) and nickel atom (Ni1) form the five-membered
non-planar nickelacyclic ring which is fused to the six-
membered carbocyclic ring. The hinge angle, defined as
the dihedral angle between planes Ni1–C7–C8 and Ni1–
C1–C6–C7 is 5.11ꢁ in molecule A and 3.78ꢁ in molecule
B. The central nickel atom (Ni2) is bonded to the penta-
methylcyclopentadienyl ring and the nickelacyclic ring.
The slip parameter defined as DM–C = avgd(Ni2–C1,
Ni1–C1–C6
C1–C6–C6
C1–Ni1–C1
Ni1–Ni2–Cg
Ni2–Ni1–Cg
113.4(2)
111.9(2)
113.01(17)
84.14(17)
151.35(3)
152.47(3)
113.50(16)
84.10(17)
152.39(3)
152.39(3)
ꢀ28 ppm, ꢀ38 ppm, ꢀ42 ppm and ꢀ53 ppm. The com-
pound 2 is paramagnetic. Magnetic moment of 2 in toluene
solution at 293 K is 3.85 lB. The total number of valence
electrons and the value of the magnetic moment suggested
that there are 2 or 4 unpaired electrons per molecule. There
were no signals observed in EPR spectrum of 2 neither at
room temperature nor at 77 K, neither in solid state nor
in benzene solution.
˚
Ni2–C6) ꢀ avgd(Ni2–C7, Ni2–C8) is 0.299 A in molecule
˚
A and 0.305 A in molecule B. These values show that the
coordination mode of the nickelacyclic ring to the central
nickel atom (Ni2) is in between g3 and g5, the same as in
compound 1.

P. Buchalski et al. / Journal of Organometallic Chemistry 691 (2006) 4080–4085
4083
In these complexes the central nickel atom had 20 VE,
the same as the nickel atom in nickelocene. Contrary to
bis-indenylnickel, where ring slippage occurred and nickel
atom was bonded to indenyl ring in the g3 manner, the
donor properties of nickelaindenyl ring in the complex 3
were decreased due to the replacement of one carbon atom
by nickel atom, what allowed the central nickel atom to be
bonded to all five atoms of the flat nickelacyclic ring. At the
same time aromatic character of the benzene ring was
reduced. Similar structures were previously reported for
analogues of metalocenes of other than nickel metals with
metalaindenyl [8] or metalafluorenyl [9] rings. The bonding
mode of the central metal atom to the metalacycle in these
compounds was g5.
We decided to synthesise complexes similar to the com-
pound 3 in the reactions of 2,20-dilithiobiphenyl and (E)-1-
lithio-1-phenyl-2-(20-lithiophenyl)ethane with pentame-
thylcyclopentadienylnickelacetylacetonate (Cp*Ni(acac)).
Wilke reported the reaction of 1,4-dilithio-1,2,3,4-tetraphe-
nyl-1,3-butadiene with Cp*Ni(acac) in which he obtained
complex of the type Cp*Ni(alkene)alkyl, but not the com-
pound with nickelacyclopentadienyl ring [4c]
Fig. 2. ORTEP view of the molecular structure of 2 showing atom
numbering scheme. Thermal ellipsoids drawn at 30% probability level.
Hydrogen atoms were omitted for the clarity.
Ph
Ph
Ph
Ph
Table 3
˚
Selected interatomic distances (A) and angles (ꢁ) for 2
+ 2 Cp*Ni(acac)
H
Ph
Ph
Ph
Ph
Molecule A
Molecule B
Ni
Cp*
Li Li
Ni1–Ni2
Ni1–C8
Ni1–C1
C1–C6
C8–C7
C7–C6
Ni2–C8
Ni2–C7
Ni2–C1
Ni2–C6
2.4778(6)
1.910(3)
1.924(4)
1.429(5)
1.412(5)
1.462(5)
2.027(4)
2.131(4)
2.367(4)
2.388(4)
2.4761(6)
1.898(4)
1.915(4)
1.429(5)
1.415(5)
1.463(5)
2.028(4)
2.112(4)
2.374(4)
2.376(4)
We believed that compounds with nickelacyclic ring
could be formed in similar reactions, but they could be sta-
ble if the nickelacycle was fused to one or two aromatic
rings. In fact in both investigated by us reactions nickelacy-
clic complexes were synthesised: the first one with nickela-
fluorenyl ring 1 and the second one with nickelaindenyl
ring 2. Such reactions proved to be the new and easy
method of the synthesis of nickelacycles. Contrary to com-
pound 3, the bonding mode of the central nickel atom to
the nickelacycle in complexes 1 and 2 was in between g3
and g5. Also the nickelacyclic ring was not flat but bent
and the nickel atom was moved towards three atoms of
the five-membered ring (Fig. 3).
Ni1–C1–C6
C1–C6–C7
C7–C8–Ni1
C8–Ni1–C1
Ni1–Ni2–Cg
Ni2–Ni1–Cg
113.77(25)
112.28(31)
114.15(25)
84.75(15)
147.08(3)
150.58(3)
113.69(25)
112.36(30)
114.36(26)
85.13(15)
146.82(3)
151.32(2)
The inductive effect of methyl groups in pentamethylcy-
clopentadienyl ring increased the electron density of both
nickel atoms. This caused the slippage and folding of nick-
elaindenyl ring in the complex 2 and the bonding mode of
central nickel atom (Ni2) changed from g5 to half way
between g3 and g5. Additionally the aromatic character
of the benzene ring was increased.
Similar situation arose in compound 1. The nickel
atom (Ni2) was bonded to only three atoms of nickelaflu-
orenyl ring. The higher electron density on the central
nickel atom pushed it away from the two carbon atoms
(C6). Steric hindrances between two pentamethylcyclopen-
tadienyl ligands caused that the second nickel atom
moved out of the plane defined by four carbon atoms
(C1, C1, C6, C6).
3. Discussion
We have recently reported the synthesis of analogues of
nickelocene in which one of the cyclopentadienyl rings was
replaced with nickelaindenyl ring [6]. We have found that
the reactions of dilithioorganic compounds with nickelo-
cene are the excellent method of the synthesis of complexes
with five-membered nickelacyclic ring [6b]
NiCp
Et
Et
Et2O
2Cp2Ni +
* 2 TMEDA
Ph
Ph
Ni
Li Li
Cp
3

4084
P. Buchalski et al. / Journal of Organometallic Chemistry 691 (2006) 4080–4085
Crystals appropriate for X-ray measurements were grown
from hexane solution. EIMS (70þeV) m/e (rel. int.) (58Ni):
538 (M+, 100%), 404 (C22H24Ni , 38%), 382 (C20H26Niþ,
2
2
60%), 248 (C10H12Niþ, 15%), 212 (C12H10Ni+, 11%), 192
2
(C10H14Ni+, 9%), 152 (C12Hþ, 11%), 133 (C10Hþ , 10%),
8
13
119 (C9Hþ11, 13%). EI HR MS: Observed: 538.16614, Calcu-
lated for C32H3858Ni2: 538.16805. 1H NMR (C6D6) d (ppm):
19, 11, ꢀ82 and ꢀ108 (broad signals). Magnetic moment in
toluene solution at 295 K was 2.786 lB.
4.2. Reaction of pentamethylcyclopentadienylnickelacetyl-
acetonate with (E)-1-lithio-1-phenyl-2-(20-lithiophenyl)-
ethene
Fig. 3. View of the bonding mode between the central nickel atom and
nickelacyclic ring.
(E)-1-lithio-1-phenyl-2-(20-lithiophenyl)ethene (1.5 g, 3.32
mmol) and 70 cm3 of diethyl ether were placed in a Schlenk
flask and cooled to ꢀ30 ꢁC. The solution of pentamethylcy-
clopentadienylnickelacetylacetonate (1.95 g, 6.68 mmol) in
20 cm3 of diethyl ether was added. The reaction was stirred
for 1 h at ꢀ30 ꢁC, and then at room temperature overnight.
After the reaction was completed, the solvent was removed
and the residue was extracted with 60 cm3 of toluene. Extract
was filtered through the alumina layer and then the solvent
was evaporated. The residue was dissolved in 10 cm3 of hex-
ane and chromatographed on neutral alumina (deactivated
with 5% of water). One brown band was collected (hexane/
toluene 10:1). The solvent was removed and brown solid com-
pound 2 was obtained (0.16 g, 0.27 mmol, 16%). Crystals
appropriate for X-ray measurements were grown from hex-
ane solution. EIMS (70 eV) m/e (rel. int.) (58Ni): 592 (M+,
100%), 456 (C26H28Niþ, 58%), 384 (C20H28Niþ, 21%), 324
4. Experimental details
All reactions were carried out in an atmosphere of dry
argon or nitrogen using Schlenk tube techniques. Solvents
1
were dried by conventional methods. H and 13C NMR
spectra were measured on a Varian Mercury 400 MHz
instrument. Mass spectra were recorded on an AMD-604
spectrometer. EPR spectra were measured on Bruker ESP
300 spectrometer in X-band. Magnetic susceptibility was
determined by NMR measurements at 298 K according
to Evans method [10], from differences in chemical shifts
of methyl group protons of toluene used as the solvent
and as the external standard. The magnetic moment was
calculated from the measurements of magnetic susceptibil-
ity. (E)-1-lithio-1-phenyl-2-(20-lithiophenyl)ethene was syn-
thesised from diphenylacetylene and ethyllithium as it was
described for n-butyl derivative [11]; 2,20-dibromobiphenyl
was synthesised according to [12] and pentamethylcyclo-
pentadienylnickelacetylacetonate according to [13]. 2,20-
Dilithiobiphenyl was synthesised from lithium and 2,
20-dibromobiphenyl in diethyl ether.
2
2
(C16H16Niþ, 13%), 266 (C16H16Ni+, 16%), 191 (C10H13Ni+,
2
20%), 133 (C10H1þ3, 12%), 119 (C9H1þ1, 16%). EI HR MS:
Observed 592.21373, Calculated for C36H4458Ni2 592.21500.
1H NMR (C6D6) d (ppm): 14, 13, 8, ꢀ28, ꢀ38, ꢀ42 and
ꢀ53 (broad signals). Magnetic moment in toluene solution
at 293 K is 3.85 lB.
4.3. Crystal structure determination of 1
4.1. Reaction of pentamethylcyclopentadienylnickelacetyl-
acetonate with 2,20-dilithiobiphenyl
The crystal was sealed in a glass capillary under nitrogen
stream. Unit cell from 6768 reflections 2.91ꢁ < h < 27.48ꢁ.
X-ray data were collected on a Nonius KappaCCD diffrac-
tometer. Data collected with subsequent u and x scans (213
frames, rotation per frame 1.5ꢁ, exposure per frame 60 s)
43,084 reflections collected, 6493 unique, 4797 above
threshold [I > 2r(I)]. Diffractometer control program COL-
LECT [14], unit cell parameters and data reduction with
Denzo and Scalepak [15], structure solved by direct meth-
ods SHELXS-97 [16] and refined on F2 by full-matrix least-
squares with SHELXL-97 [17]. Two independent molecules
were found in asymmetric unit, each molecule lies on crys-
tallographic mirror plane. In molecule B one of the penta-
methylocyclopentadiene ligands is highly disordered at
several positions and it was extremely difficult to find
appropriate model for it. Due to the above difficulties only
carbon atoms with approximate s.o.f. and isotropic thermal
Pentamethylcyclopentadienylnickelacetylacetonate (0.97 g,
3.32 mmol) and 20 cm3 of diethyl ether were placed in a
Schlenk flask and cooled to ꢀ30 ꢁC. The solution of 2,20-
dilithiobiphenyl in diethyl ether (17 cm3, 0.105 mol/dm3,
1.79 mmol) was added. The reaction was stirred for 1 h at
ꢀ30 ꢁC, and then at room temperature overnight. After
the reaction was completed, the solvent was removed and
the residue was extracted with 40 cm3 of toluene. Extract
was filtered through the alumina layer and then the solvent
was evaporated. The residue was dissolved in 10 cm3 of hex-
ane and chromatographed on neutral alumina (deactivated
with 5% of water). One red-brown band was collected (hex-
ane/toluene 4:1). The solvents were removed and brown
solid compound 1 was obtained (0.86 g, 1.6 mmol, 96%).

P. Buchalski et al. / Journal of Organometallic Chemistry 691 (2006) 4080–4085
4085
ꢀ3
˚
(c) M. Herker, F.H. Kohler, M. Schwaiger, B. Weber, J. Organomet.
Chem. 658 (2002) 266;
displacement parameters at the peaks >1 e A in Fourier
difference maps were introduced into final refinement. No
attempt was made to attach hydrogen atoms to the methyl
groups in this ligand. All the reminding hydrogen atoms
were placed in calculated positions and refined using a rid-
ing model. Three methyl groups C(12a), C(16a) and C(10b)
appeared to be disordered in two positions due to the crys-
tallographic mirror plane. Final R = 0.046 (0.071 for all
reflections), wR = 0.117 (0.126 for all reflections).
(d) M.P. Castellani, S.J. Geib, A.L. Rheingold, W.C. Trogler,
Organometallics 6 (1987) 1703;
(e) P.R. Sharp, K.N. Raymond, J.C. Smart, R.J. McKinney, J. Am.
Chem. Soc. 103 (1981) 753;
(f) E.E. Bunel, L. Valle, N.L. Jones, P.J. Carroll, M. Gonzales, N.
Munoz, J.M. Manriquez, Organometallics 7 (1988) 789;
(g) W.T. Scroggins, M.F. Rettig, R.M. Wing, Inorg. Chem. 15 (1976)
1381.
[3] (a) J.L. Priego, L.H. Doerrer, L.H. Rees, M.L.H. Green, Chem.
Commun. (2000) 779;
(b) L.D. Field, T.W. Hambley, Taian He, P.A. Humphrey, C.M.
Lindall, A.F. Masters, Aust. J. Chem. 49 (1996) 889;
(c) E. Dubler, M. Textor, H.-R. Oswald, A. Saltzer, Angew. Chem.
86 (1974) 125.
4.4. Crystal structure determination of 2
The crystal was sealed in a glass capillary under nitrogen
stream. Unit cell from 10,777 reflections 2.91ꢁ < h < 27.48ꢁ.
X-ray data were collected on a Nonius KappaCCD diffrac-
tometer. Data collected with u scans (121 frames, rotation
per frame 1.5ꢁ, exposure per frame 45 s) 36,054 reflections
collected, 13,442 unique, 7242 above threshold [I > 2r(I)].
Diffractometer control program COLLECT [14], unit cell
parameters and data reduction with Denzo and Scalepak
[15], structure solved by direct methods SHELXS-97 [16] and
refined on F2 by full-matrix least-squares with SHELXL-97
[17]. All the hydrogen atoms were placed in calculated posi-
tions and refined using a riding model. Final R = 0.053,
wR = 0.094.
[4] (a) S.A. Westcott, A.K. Kakkar, G. Stringer, N.J. Taylor, T.B.
Marder, J. Organomet. Chem. 394 (1990) 777;
(b) O.N. Babkina, T.A. Bazhenova, N.M. Bravaya, M.Yu. Antipin,
K.A. Lysenko, Izv. Akad. Nauk SSSR, Ser. Khim. (1996) 1529;
(c) U. Denninger, J.J. Schneider, G. Wilke, R. Goddard, R. Kro¨mer,
C. Kruger, J. Organomet. Chem. 459 (1993) 349.
¨
[5] J.M. Manriquez, M.D. Ward, W.M. Reiff, J.C. Calabrese, N.L.
Jones, P.J. Carroll, E.E. Bunel, J.S. Miller, J. Am. Chem. Soc. 117
(1995) 6182.
[6] (a) P. Buchalski, A. Pietrzykowski, S. Pasynkiewicz, L.B. Jer-
zykiewicz, J. Organomet. Chem. 690 (2005) 1523;
(b) P. Buchalski , S. Pasynkiewicz, A. Pietrzykowski, A. Piłka, K.
´
Suwinska, Inorg. Chem. Commun. 9 (2006) 375.
[7] J. Mu¨ller, H. Dorner, G. Huttner, H. Lorenz, Angew. Chem. 85
(1973) 1117.
[8] (a) M. King, E.M. Holt, P. Radnia, J.S. McKennis, Organometallics
1 (1982) 1718;
Acknowledgement
(b) H. Wadepohl, T. Borchert, K. Buchner, M. Herrmann, F.-J.
¨
The authors thank the Ministry of Education and Science
for financial support of this work (GrantNo. 4 T09A 012 25).
Paffen, H. Pritzkow, Organometallics 14 (1995) 3817.
[9] (a) C. Perthuisot, B.L. Edelbach, D.L. Zubris, W.D. Jones, Organo-
metallics 16 (1997) 2016;
ˇ
´
(b) S. Kumaraswamy, S.S. Jalisatgi, A.J. Matzger, O.S. Miljanic,
K.P.C. Vollhardt, Angew. Chem., Int. Ed. 43 (2004) 3711.
[10] (a) D.F. Evans, J. Chem. Soc. (1959) 2003;
Appendix A. Supplementary data
Crystallographic data for the structural analysis of 1 and
2 have been deposited with the Cambridge Crystallo-
graphic Data Centre Nos. CCDC 600976 and 600977. Cop-
ies of this information may be obtained free of charge from
The Director, CCDC, 12, Union Road, Cambridge, CB2
1EZ, (fax +44 1223 336033 or e-mail: deposit@ccdc.cam.
ac.uk or http://www.ccdc.cam.ac.uk). Supplementary data
associated with this article can be found, in the online ver-
sion, at doi:10.1016/j.jorganchem.2006.06.013.
(b) T.H. Crawford, J. Swanson, J. Chem. Educ. 48 (1971) 382;
(c) S. Braun, H.O. Kalinowski, S. Berger, 150 and More Basic NMR
Experiments, Wiley-VCH, New York, 1998.
[11] M.D. Rausch, L.P. Klemann, 1-Lithio-1-phenyl-n-butyl-2-(20-lithio-
phenyl)ethene as an intermediate for metallaindene compounds, in:
R.B. King, J.J. Eisch (Eds.), Organometallic Synthesis, vol. 3,
Elsevier, Amsterdam, 1986, p. 507.
[12] T.K. Dougherty, K.S.Y. Lau, F.L. Hedberg, J. Org. Chem. 48 (1983)
5273.
[13] M.E. Smith, R.A. Andersen, J. Am. Chem. Soc. 118 (1996)
11119.
[14] B.V. Nonius, ‘‘COLLECT’’ data collection software, 1998.
[15] Z. Otwinowski, W. Minor, Processing of X-ray diffraction data
collected in oscillation mode, in: C.W. CarterJr., R.M. Sweet (Eds.),
Methods in Enzymology, Macromolecular Crystallography, Part A,
vol. 276, Academic Press, New York, 1997, pp. 307–326.
[16] G.M. Sheldrick, SHELXS-97, Acta Crystallogr. Sect. A 46 (1990)
467.
References
[1] P. Seiler, J.D. Dunitz, Acta Crystallogr., Sect. B, Struct. Crystallogr.
Cryst. Chem. 36 (1980) 2255.
[2] (a) I.E. Zanin, M.Yu. Antipin, Kristallografiya (Russ.) (Crystallogr.
Rep.) 46 (2001) 1030;
[17] G.M. Sheldrick, SHELXL-97Program for the Refinement of Crystal
Structures, University of Go¨ttingen, Go¨ttingen, Germany, 1997.
(b) D. Vos, A. Salmon, H.-G. Stammler, B. Neumann, P. Jutzi,
Organometallics 19 (2000) 3874;