Bis-nickel-bridged p-terphenyl dianion - Synthesis and structures

Article abstract of DOI:10.1016/j.jorganchem.2015.04.037

In this paper we present the synthesis and characterisation of novel bisnickelacyclic complexes. We carried out the reaction between 2,2′,2″,5′-tetralithio-1,1′,4′,1″-terphenyl and nickelocene in which bisnickelacyclic-dilithium complex was formed. It rep

Full text of DOI:10.1016/j.jorganchem.2015.04.037

Journal of Organometallic Chemistry 789-790 (2015) 40e45
Contents lists available at ScienceDirect
Journal of Organometallic Chemistry
journal homepage: www.elsevier.com/locate/jorganchem
Bis-nickel-bridged p-terphenyl dianion e Synthesis and structures
,
Piotr Buchalski a *, Roman Pacholski a, Jan Gustowski a, Włodzimierz Buchowicz a,
a
b
c
ꢀ
Karol Molga , Aleksander Shkurenko , Kinga Suwinska
a Warsaw University of Technology, Faculty of Chemistry, Koszykowa 75, 00-662 Warsaw, Poland
b Institute of Physical Chemistry of the Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
c
ꢀ
Faculty of Mathematics and Natural Sciences, Cardinal Stefan Wyszynski University in Warsaw, K. Woycickiego 1/3, 01-938 Warszawa, Poland
a r t i c l e i n f o
a b s t r a c t
Article history:
In this paper we present the synthesis and characterisation of novel bisnickelacyclic complexes. We
carried out the reaction between 2,20,200,50-tetralithio-1,10,40,100-terphenyl and nickelocene in which bis-
nickelacyclicedilithium complex was formed. It represented the contact ion pair that consisted of
nickelacyclic dianion (the first of it's kind) and lithium cations. Exchange of solvent from diethyl ether to
DME (1,2-dimethoxyethane) afforded solvent separated ionic pair. Both of these complexes exhibited
paramagnetic behaviour, so structural investigations had to be carried out by means of X-ray diffraction.
DFT calculations were employed for better understanding of electronic structure of these complexes.
© 2015 Elsevier B.V. All rights reserved.
Received 9 December 2014
Received in revised form
9 April 2015
Accepted 16 April 2015
Available online 5 May 2015
Keywords:
Nickel
Lithium
Cyclopentadienyl ligands
DFT
X-ray diffraction
Introduction
Results and discussion
Although several analogues of fluorenyllithium or fluorenyl-
alkali metal complexes containing main group elements have
been reported so far [1] there are still only a few examples of
metallafluorenyllithium complexes containing transition metals.
The only examples are the compounds of zirconium [2] and nickel
[3]. Such complexes can be useful in organic syntheses [2b], or can
act as a donor of metallafluorenyl ligand to other metal atoms
[4e6].
Our goal was to synthesize the compound which can act as a
donor of metallafluorenyl ligand with two coordination centers and
can act as a building block for organonickel oligomers or polymers.
Such organometallic polymers are recently of general interest
[7e12].
The syntheses of 2,20,200,50-tetrabromo-1,10,40,100-terphenyl, our
starting material, was reported earlier [13]. Because we were not
able to obtain the product with satisfactory yield, we decided to
modify the conditions of Suzuki cross-coupling. The best results
were obtained for the catalytic system that is described in the
experimental part. This system worked very well for other cross-
coupling reactions we have carried out, especially when
substituted phenylboronic acids were used.
The reaction between 2,20,200,50-tetralithio-1,10,40,100-terphenyl
and nickelocene has been carried out in a diethyl ether at room
temperature.
From a dark red-brown solution red crystals of 1 appropriate for
X-ray diffraction studies were grown. The molecular structure of 1
is presented in Fig. 1. Crystal data, data collection and refinement
parameters are given in Table 1. As far as we know compound 1 is
the first example of the organometallic complex with two five-
membered metallacyclic rings which forms the dianion. The com-
pound crystallises in a triclinic crystal system. Four diethyl ether
molecules are coordinated to two lithium atoms. The molecule
contains two planar five-membered nickelacycles for which the
maximum deviation from the mean plane defined by the C1, C6, C7,
In this paper we report the synthesis, characterization and
properties of the first organometallic complexes with two five-
membered metallacyclic rings which form the dianions.
* Corresponding author. Tel.: þ48 22 234 78 59; fax: þ48 22 234 54 62.
E-mail address: pjb@ch.pw.edu.pl (P. Buchalski).
http://dx.doi.org/10.1016/j.jorganchem.2015.04.037
0022-328X/© 2015 Elsevier B.V. All rights reserved.

P. Buchalski et al. / Journal of Organometallic Chemistry 789-790 (2015) 40e45
41
spectrum of what could be dissolved from dry 1 there were no
signals other than solvent's, in the range between ꢀ120e120 ppm
e most probably the compound is paramagnetic.
Behaviour of
1
is somehow similar to the 9-
nickelafluorenyllithium complex [3] which after drying under
vacuum turned into a yellow powder, which was not soluble again
in diethyl ether.
Similarly to nickelafluorenyllithium, compound 1 forms com-
plex 2 with DME.
After drying compound 2 most probably looses 4 molecules of
DME and becomes a contact ion pair 2a, which most probably has
only one DME molecule co-ordinated to each lithium ion, as it was
for 9-nickelafluorenyllithium complex [3]. We cannot verify this
assumption because the complex is paramagnetic and so far we
were not able to obtain crystals appropriate for X-ray
measurements.
In 1H NMR spectrum of 2 there were no signals other than
solvent's, in the range between ꢀ120 e 120 ppm both at 20 ꢁC and
at 60 ꢁC. Magnetic moment of 2 in DME solution at 295 K is 3.05 mB
,
what indicates that the compound is paramagnetic. The total
number of valence electrons and the value of the magnetic moment
suggested that there are 2 unpaired electrons per molecule. In the
EPR spectrum of 2 in the solid state at 77 K there is an anisotropic
single line of rhombic symmetry. The parameters of the signal are:
Fig. 1. ORTEP view of the molecular structure of 1 showing atom numbering scheme.
Thermal ellipsoids drawn at 30% probability level. Selected distances [Å] and angles
[ꢁ]: C1eNi1 1.893 (3), C8eNi1 1.895 (3), Li2eNi1 2.576 (6), C1eLi2 2.804 (7), C6eLi2
2.902 (8), C7eLi2 2.645 (7), C8eLi2 2.347 (7); C1eNi1eC8 84.60 (13), C8eLi2eNi1
44.99 (13).
g1 ¼ 2.253, g2 ¼ 2.111, g3 ¼ 2.043,
D
H1 ¼ 140 G,
D
H2 ¼ 100 G,
D
H3 ¼ 80 G. Relatively large shift of g value from the g value for free
electron suggests that the paramagnetic centre is located on the
nickel atom.
C8 and Ni atoms is 0.0072 Å for C7. In fact all carbon atoms of
benzene rings and two nickel atoms form a plane for which the
maximum deviation is 0.0413 Å for C9. The average length of the Ni
e C1 and Ni e C8 bonds is 1.89 Å which is in the range of nickel-
ecarbon single bond and identical to the distances in 9-
nickelafluorenyllithium complex [3]. Complex 1 forms a contact
ion pair in which lithium cation interacts with two members of the
nickelacyclic ring (C8 and Ni). The similar interaction occurs in 9-
nickelafluorenyllithium complex [3].
The compound 1 is difficult to handle because after drying un-
der vacuum it is quite difficult to dissolve it again in diethyl ether
most probably due to its partial decomposition. This is the reason
why it could be identified only by X-ray diffraction. In 1H NMR
Crystals of 2 appropriate for X-ray diffraction studies were
grown from DME solution at room temperature. The molecular
structure of 2 is presented in Fig. 2. Crystal data, data collection and
refinement parameters are given in Table 1. Compound 2 represents
a
solvent separated ion pair which is similar to the 9-
nickelafluorenyllithium complex [3]. The bis-nickel-bridged p-ter-
phenyl forms a dianion. All carbon atoms of benzene rings and two
nickel atoms form a plane for which the maximum deviation is
0.0588 Å for C1. Each lithium cation of 2 is bonded to three DME
molecules and the average lithiumenickel distance is 6.08 Å which
is shorter than the distance in 9-nickelafluorenyllithium complex
(6.50 Å).

42
P. Buchalski et al. / Journal of Organometallic Chemistry 789-790 (2015) 40e45
Table 1
Crystal data and structure refinement.
1
2
Empirical formula
Formula weight
Temperature/K
Crystal system
Space group
a/Å
C44H60Li2Ni2O4
784.22
100(2)
triclinic
P-1
8.8339(5)
9.4887(5)
12.9468(7)
78.324(5)
85.111(4)
76.157(5)
1031.1(1)
1
C26H40LiNiO6
514.23
100.0(2)
triclinic
P-1
9.4927(2)
11.6032(3)
14.1981(3)
67.075(2)
89.858(2)
72.910(2)
1365.55(6)
2
b/Å
c/Å
ꢁ
ꢁ
ꢁ
/
a
/
b
/
g
Volume/Å3
Z
rcalcmg/mm3
1.263
0.952
1.251
0.746
m
/mmꢀ1
F(000)
418.0
550.0
Crystal size/mm3
Radiation
0.656 ꢂ 0.242 ꢂ 0.158
0.18 ꢂ 0.14 ꢂ 0.12
MoK
a
(
l
¼ 0.71073)
MoK
a
(
l
¼ 0.71073)
2
Q
range for data collection
6.4188e58.7584ꢁ
5.828e53.564ꢁ
Index ranges
ꢀ12 ꢃ h ꢃ 12, ꢀ12 ꢃ k ꢃ 12, ꢀ13 ꢃ l ꢃ 17
0 ꢃ h ꢃ 12, ꢀ13 ꢃ k ꢃ 14, ꢀ17 ꢃ l ꢃ 17
Reflections collected
Independent reflections
Data/restraints/parameters
Goodness-of-fit on F2
8687
20897
4909 [Rint ¼ 0.0582, Rsigma ¼ 0.0446]
4909/0/239
1.028
5786 [Rint ¼ 0.0489, Rsigma ¼ 0.0307]
5786/0/313
1.185
Final R indexes [I ꢄ 2
s
(I)]
R1 ¼ 0.0603, wR2 ¼ 0.1468
R1 ¼ 0.0756, wR2 ¼ 0.1593
1.39/ꢀ0.76
R1 ¼ 0.0521, wR2 ¼ 0.1310
R1 ¼ 0.0602, wR2 ¼ 0.1356
0.64/ꢀ0.41
Final R indexes [all data]
Largest diff. peak/hole/e Åꢀ3
Due to the differences between magnetic properties of 9-
nickelafluorenyllithium (which is diamagnetic) and complex 2,
we tried to investigate its electronic structure with DFT methods.
Results obtained using this approach turned out to be inconsistent
with the experimental results. Diamagnetic singlet configuration
of nickelacyclic dianion turned out to be 113 kJ/mol lower than
paramagnetic triplet state. Addition of thermal corrections to
electronic energy resulted in 105 kJ/mol Gibbs free energy differ-
ence between singlet and triplet state at 298 K. Mulliken popu-
lation analysis [14] of triplet state shows the presence of unpaired
electrons on one of the nickel atoms. We were not able to locate
the antiferromagnetic singlet state. 2 forms solvent separated ionic
pairs in the solid state so we can assume that 2 is fully dissociated
in the solution. The reason for this inconsistency is unclear. This
result may lead to two possible conclusions. The first one is that
the used level of theory is insufficient for given compounds. The
second one is that some intermolecular effects take place in the
solution.
The concept of the synthesis of 1 was to obtain a building block
for oligomers containing metallacycles. In order to check weather 1
is suitable for this purpose we carried out the reaction between 1
and Cp*Ni(acac).
Earlier reactions between 9-nickelafluorenyllithium complex
and Cp*Ni(acac) or Cp*Co(acac) resulted in analogues of
Fig. 2. ORTEP view of the molecular structure of 2 showing atom numbering scheme. Thermal ellipsoids drawn at 30% probability level. Methyl carbon atoms of DME are omitted
for clarity. Selected distances [Å] and angles [ꢁ]: C1eNi1 1.889 (3), C8eNi1 1.903 (3), Li1eNi1 5.953 (7); C1eNi1eC8 84.46 (13).

P. Buchalski et al. / Journal of Organometallic Chemistry 789-790 (2015) 40e45
43
nickelocene [5] or cobaltocene [6] with one metallacycle as main or
the only products.
which form the dianions. We have examined the reaction be-
tween 1 and Cp*Ni(acac) and isolated new nickelacyclic com-
pounds with two or four nickel atoms in molecules. These
compounds may be used as catalysts in Suzuki cross-coupling
reactions.
To our surprise in the reaction between 1 and two equivalents of
Cp*Ni(acac) a mixture of products was obtained. The products were
separated by column chromatography on neutral alumina deacti-
vated with 5% of water. We have collected three main fractions,
although we could see that the compounds slowly decompose
during chromatography. Especially purification of the mixture of 4
and 5 was very difficult and only very small amounts of pure
products could be isolated.
Experimental section
All reactions were carried out in an atmosphere of dry argon or
nitrogen using Schlenk tube techniques. Solvents were dried by
Compound 3 was formed most probably due to the decompo-
sition of 5. It is a nickelocene with one cyclopentadienyl ring and
one pentamethylcyclopentadienyl ring.
conventional methods. 1H and 13C NMR spectra were measured on
a Varian Mercury 400 MHz instrument. Mass spectra were recorded
on an AMD-604 spectrometer. Magnetic susceptibility was deter-
mined by NMR measurements at 298 K according to Evans method
[16], from differences in chemical shifts of methyl group protons of
DME used as the solvent and as the external standard. Diamagnetic
corrections were calculated using Pascal's constants [17]. (2-
bromophenyl)boronic acid [18], 1,4-dibromo-2,5-diiodobenzene
[19] and Pd(PPh3)4 [20] were prepared according to the literature
procedures.
Compounds 4 and 5 are brown solids. In the 1H NMR spectra of 4
and 5 there were no signals other than solvent's, in the range
between ꢀ120 e 120 ppm most probably due to the paramagnetic
properties of these complexes. They were characterized by EIMS
spectra. EIMS spectrum of 4 showed the parent ion at m/e 544 (58Ni
calc.) with an isotopic pattern characteristic for two nickel atoms in
the molecule. EIMS spectrum of 5 showed the parent ion at m/e 858
(
58Ni calc.) with an isotopic pattern characteristic for four nickel
Synthesis of 2,20,200,50-tetrabromo-1,10,40,100-terphenyl
atoms in the molecule. Attempts of growing monocrystals of both
compounds has so far failed.
Organonickel compounds are known to be efficient catalysts in
the formation of carbonecarbon bonds [15]. We have checked the
catalytic activity of 2 and the mixture of 4 and 5 (because isolation
of pure compounds proved to be very difficult) in Suzuki and
Kumada cross-coupling reactions.
A 1 L three-necked flask equipped with an effective magnetic
stirrer and reflux condenser with a balloon was charged with 1,2-
dibromo-4,5-diiodobenzene (14.64 g, 30 mmol), (2-bromophenyl)
boronic acid (13.25 g, 66 mmol, 2.2 equiv.), K2CO3 (24.52 g, 0.18 mol,
6 equiv.), BnNMe3Cl (1.114 g, 6 mmol, 0.2 equiv) and Pd(PPh3)4
While in Kumada reaction between phenylmagnesium bromide
and 3-bromotoluene the product was obtained with moderate yield
(64% for 2 and 57% for the mixture of 4 and 5), in the cross-coupling
of 4-bromoacetophenone with phenylboronic acid, 4-
acetylbiphenyl was isolated with a very good yield (96% for 2 and
93% for the mixture of 4 and 5).
(2.08 g, 1.8 mmol, 0.06 equiv.). Oxygen free water (90 mL), n-pentyl
alcohol (90 mL) and toluene (300 mL) were added. The flask was
placed in oil bath preheated to 100ꢁ and vigorously stirred for 24 h.
After cooling to room temperature 200 mL of water and 400 mL of
dichloromethane were added. The mixture was filtered over Celite
pad to remove small amount of palladium black. Organic phase was
separated, washed with 100 mL of brine, dried over MgSO4 and
dried. Remaining residue was dissolved in 70 mL of hot THF. The
product was precipitated with 250 mL of hexane, filtered and dried
under vacuum. 11.5 g (21 mmol, 70%) of white powder was ob-
tained. 1H NMR was in agreement with the literature data. 1H NMR
Conclusions
We have described the synthesis of first organometallic
complexes (1 and 2) with two five-membered metallacyclic rings

44
P. Buchalski et al. / Journal of Organometallic Chemistry 789-790 (2015) 40e45
(acetone-d6) (20 ꢁC)
d
(ppm): 7.39e7.45 (m, 4H), 7.53 (tt, 2H), 7.66
Reaction of 1 with Cp*Ni(acac)
(d, 2H), 7.77 (dd, 2H).
2,20,200,50-tetrabromo-1,10,40,100-terphenyl. (273 mg, 0.5 mmol)
and 80 mL of diethyl ether were placed in a Schlenk flask. Then
2.5 mmol of n-butyllithium (solution in hexane) was added at 0 ꢁC.
Reaction was stirred 1 h at 0 ꢁC, warmed to room temperature and
stirred for further 4 h. The solvent was removed under vacuum. The
pale-yellow precipitate was washed 3 times with 50 mL of hexane
and dried under vacuum. Then 100 mL of diethyl ether and 189 mg
(1 mmol) of nickelocene were added to the Schlenk flask. The re-
action was carried out for 12 h at room temperature. Then the
precipitate was allowed to settle and the clear solution of 1 was
transferred to another Schlenk flask. The solution of Cp*Ni(acac)
(293 mg, 1 mmol) in 20 mL of diethyl ether was added. The reaction
was carried out for 24 h at room temperature. Solvents were
removed under vacuum. The solid residue was extracted with two
portions (30 mL) of toluene. The combined extracts were filtered
and concentrated to approximately 10 mL. Alumina was added and
the solvent was removed under vacuum. The products, absorbed on
alumina, were placed at the top of the column and chromato-
graphed on alumina (deactivated with 5% water) with hexane/
toluene mixtures as eluents. There were several colored bands, but
three main were separated and collected. The first, green fraction
(hexane) after evaporation to dryness gave solid identified as 3
(yield 0.080 g, 0.31 mmol, ca. 62%). EIMS (70 eV) m/e (rel int) (58Ni):
258 (100%, Mþ), 192 (43%, C10H14Niþ), 176 (17%, C9H10Niþ). Anal.
Calcd for C15H20Ni: C, 69.56, H, 7.78. Found: C, 69.28; H, 7.65. The
second brown fraction (hexane/toluene, 3:2) gave a solid identified
as 5 (yield 20 mg, 0.02 mmol, ca. 4%). EIMS (70 eV) m/e (rel int)
Synthesis of 1
2,20,200,50-tetrabromo-1,10,40,100-terphenyl (545 mg, 1 mmol) and
80 mL of diethyl ether were placed in a Schlenk flask. Then 5 mmol
of n-butyllithium (solution in hexane) was added at 0 ꢁC. Reaction
was stirred 1 h at 0 ꢁC, warmed to room temperature and stirred for
further 4 h. The solvent was removed under vacuum. The pale-
yellow precipitate was washed 3 times with 50 mL of hexane and
dried under vacuum. Then 100 mL of diethyl ether and 378 mg
(2 mmol) of nickelocene were added to the Schlenk flask. The re-
action was carried out for 12 h at room temperature. Then the
precipitate was allowed to settle and the clear red-brown solution
of 1 was transferred to another Schlenk flask. Crystals appropriate
for X-ray measurements were grown from saturated diethyl ether
solution of 1 at room temperature.
Synthesis of 2
2,20,200,50-tetrabromo-1,10,40,100-terphenyl. (545 mg, 1 mmol) and
80 mL of diethyl ether were placed in a Schlenk flask. Then 5 mmol
of n-butyllithium (solution in hexane) was added at 0 ꢁC. Reaction
was stirred 1 h at 0 ꢁC, warmed to room temperature and stirred for
further 4 h. The solvent was removed under vacuum. The pale-
yellow precipitate was washed 3 times with 50 mL of hexane and
dried under vacuum. Then 100 mL of diethyl ether and 378 mg
(2 mmol) of nickelocene were added to the Schlenk flask. The re-
action was carried out for 12 h at room temperature. Then the
precipitate was allowed to settle and the clear red-brown solution
of 1 was transferred to another Schlenk flask.
A 2 mL amount of dimethoxyethane was added to a solution of 1
in diethyl ether, and an orange precipitate was formed. The solution
was removed, the solid was washed with 5 mL of diethyl ether and
5 mL of hexane and dried. 550 mg of 2 (0.53 mmol, 53%) of dark
orange powder was obtained. Complex 2 crystallized as orange
needles from dimethoxyethane solution at room temperature.
Anal. Calcd for 2 C52H80Li2Ni2O12: C, 60.73, H, 7.84. Found: C, 62.93;
H, 7.18. These results were obtained after short-term drying of the
compound. They show that 2 stepwise looses coordinated DME.
First a compound with most probably 2 DME molecules per one
lithium atom is formed. Prolonged drying under vacuum at
elevated temperature most probably leads to the formation of
contact ion pair 2a which has only one DME molecule co-ordinated
to each lithium ion. Elemental analysts of the dried product gave
the result: C, 64.25, H, 6.37 The formula of hipotetical 2a is
(
58Ni): 858 (12%, Mþ), 456 (100%, C30H38Niþ), 292 (36%, C18H18Niþ),
230 (33%, C18Hþ14). Anal. Calcd for C48H50Ni4: C, 66.91, H, 5.85.
Found: C, 67.12; H, 5.71. The third, brown fraction (hexane/toluene,
1:1) gave a solid identified as 4 (yield 25 mg, 0.045 mmol, ca. 9%).
EIMS (70 eV) m/e (rel int) (58Ni): 544 (100%þ, Mþ), 478 (28%,
C
C
28H26Niþ2 ), 351 (25%, C23H17Niþ), 230 (25%, C18H14). Anal. Calcd for
33H32Ni2: C, 72.59, H, 5.91. Found: C, 72.97; H, 5.63.
Procedure for Kumada coupling
100 mg of 3-bromotoluene (1.0 eq.),1.2 mL of phenylmagnesium
bromide solution (c ¼ 0.73 M) (1.5 eq.), 3% of catalyst (mixture of 4
and 5) and 2 mL of THF were placed in round-bottom flask. The
flask was sealed with serum cap. Reaction was carried out for 21 h
at room temperature. Reaction mixture was GC tested. Yield 57%.
Procedure for Suzuki coupling
C
36H40Li2Ni2O4: and its calculated composition: C, 64.73, H, 6.04.
91 mg of phenylboronic acid (1.5 eq.), 99 mg of 4-
bromoacetophenone (1.0 eq.), 318 mg of K3PO4 and 3% of catalyst
(mixture of 4 and 5) were placed in a round-bottom flask. After-
wards 3 mL of toluene were added and the flask was sealed with
serum cap. Reaction was carried out for 3 h at 90 ꢁC. Reaction
mixture was GC tested. Yield 93%.
Procedure for Kumada coupling
100 mg of 3-bromotoluene (1.0 eq.),1.2 mL of phenylmagnesium
bromide solution (c ¼ 0.73 M) (1.5 eq.), 3% of 2 as catalyst and 2 mL
of THF were placed in round-bottom flask. The flask was sealed
with serum cap. Reaction was carried out for 21 h at room tem-
perature. Reaction mixture was GC tested. Yield 64%.
X-ray structure determination of 1
Selected crystallographic data and further details of the data
collection and refinement for crystals are summarized in Table 1. X-
ray diffraction data were collected at 100 K on Agilent SuperNova
Procedure for Suzuki coupling
100 mg of phenylboronic acid (1.5 eq.), 109 mg of 4-
bromoacetophenone (1.0 eq.), 345 mg of K3PO4 and 3% of 2 as
catalyst were placed in a round-bottom flask. Afterwards 3 mL of
toluene were added and the flask was sealed with serum cap. Re-
action was carried out for 3 h at 90 ꢁC. Reaction mixture was GC
tested. Yield 96%.
diffractometer equipped with a Mo-Ka micro-focus X-ray source.
Experimental temperatures were regulated using an Oxford Cry-
osystems open-flow nitrogen cryostat. The raw data were treated
with the CrysAlisPro [21] (version 1.171.35.15) crystallographic
package. Structures were solved by direct methods with SHELXS-97
[22] and refined against F2 with full-matrix least-squares using the

P. Buchalski et al. / Journal of Organometallic Chemistry 789-790 (2015) 40e45
45
(c) Y. Liu, D. Ballweg, T. Müller, I.A. Guzei, R.W. Clark, R. West, J. Am. Chem.
Soc. 124 (2002) 12174;
(d) Y. Liu, T.C. Stringfellow, D. Ballweg, I.A. Guzei, R. West, J. Am. Chem. Soc.
124 (2002) 49;
(e) H. Bock, M. Sievert, C.L. Bogdan, B.O. Kolbesen, A. Wittershagen, Organo-
metallics 18 (1999) 2387;
SHELXL-97 [23]. All non-H atoms were refined with anisotropic
atomic displacement parameters, while the hydrogen atoms were
placed in geometrically calculated positions refined using a riding
model.
(f) D. Ballweg, Y. Liu, I.A. Guzei, R. West, Silicon Chem. 1 (2002) 57.
[2] (a) C.L. Hilton, B.T. King, Organometallics 25 (2006) 4058;
(b) B. Kumar, C.E. Strasser, B.T. King, J. Org. Chem. 77 (2012) 311.
X-ray structure determination of 2
ꢀ
ꢀ
[3] P. Buchalski, I. Grabowska, E. Kaminska, K. Suwinska, Organometallics 27
(2008) 2346.
Selected crystallographic data and further details of the data
collection and refinement for crystals are summarized in Table 1. X-
ray data were collected on a Nonius KappaCCD diffractometer using
ꢀ
[4] P. Buchalski, I. Grabowska, A. Karaskiewicz, K. Suwinska, L. Jerzykiewicz, Or-
ganometallics 27 (2008) 3316.
[5] P. Buchalski, A. Koziol, K. Suwinska, Acta Cryst. C 64 (2008) m274.
[6] P. Buchalski, E. Kaminska, K. Piwowar, K. Suwinska, L. Jerzykiewicz, F. Rossi,
F. Laschi, F. Fabrizi de Biani, P. Zanello, Inorg. Chem. 48 (2009) 4934.
graphite-monochromated Mo-Ka radiation. Diffractometer control
program Collect [24], unit cell parameters and data reduction with
Denzo and Scalepak [25], structure solved by direct methods
SHELXS-97 [22] and refined on F2 by full-matrix least-squares with
SHELXL-97 [23]. All the hydrogen atoms were placed in calculated
positions and refined using a riding model.
ꢀ
[7] P. Nguyen, P. Gomez-Elipe, I. Manners, Chem. Rev. 99 (1999) 1515.
[8] W. Lin, W.J. Rieter, K.M.L. Taylor, Angew. Chem. Int. Ed. 48 (2009) 650.
[9] G.R. Whittell, I. Manners, Adv. Mater. 9 (2007) 3439.
[10] A.S. Abd-El-Aziz, Macromol. Rapid Commun. 23 (2002) 995.
[11] H. Nishihara, M. Kurashina, M. Murata, Macromol. Symp. 196 (2003) 27.
[12] F. Katoa, D.A. Rider, Annu. Rep. Prog. Chem. Sect. A Inorg. Chem. 109 (2013)
277.
Computational details
[13] L. Li, J. Xiang, C. Xu, Org. Lett. 9 (2007) 4877.
[14] R.S. Mulliken, J. Chem. Phys. 23 (1955) 1833.
ꢀ
[15] See for example: (a) J. Hassan, M. Sevignon, C. Gozzi, E. Schulz, M. Lemaire,
Geometry optimizations were accomplished using Minnesota
functional M06-L [26] with 6-311þþG(2df,2p) [27] basis set as
implemented in Gaussian for carbon and hydrogen atoms and def2-
TZVP [28] for nickel atoms. Redefined TZVP basis set was suggested
for 3d period by Truhlar and co-workers [29]. Diffusion functions
were included because of anionic character of investigated mole-
cule. Def2-TZVPD basis set was obtained using EMSL basis set ex-
change database [30]. Unrestricted approach was applied for all
systems. Conductor-like polarizable continuum model [31] with
THF as solvent was applied to self-consistent reaction field calcu-
lations. Molecular geometries were optimized to minimum and
confirmed by frequency calculation with no imaginary frequencies
found. Extra quadratic step using XQC keyword was added in order
solve some more difficult to converge states [32]. Energies of each
state are treated as sum of electronic energy and zero-point
correction [33]. Exact energies and Mulliken charges and spin
densities summed into heavy atoms are listed in supporting info.
All DFT calculations were done using Gaussian 09 suite of programs
[34].
Chem. Rev. 102 (2002) 1359;
(b) M.R. Netherton, G.C. Fu, Adv. Synth. Catal. 346 (2004) 1525;
(c) S. Gu, P. Ni, W. Chen, Chin. J. Catal. 31 (2010) 875;
(d) A.M. Oertel, V. Ritleng, M.J. Chetcuti, Organometallics 31 (2012) 2829;
(e) J. Breitenfeld, M.D. Wodrich, X. Hu, Organometallics 33 (2014) 5708.
[16] (a) D.F. Evans, J. Chem. Soc. (1959) 2003;
(b) T.H. Crawford, J. Swanson, J. Chem. Edu. 48 (1971) 382;
(c) S. Braun, H.O. Kalinowski, S. Berger, 150 and More Basic NMR Experiments,
Wiley e VCH, 1998;
(d) E.M. Schubert, J. Chem. Edu. 69 (1992) 62.
[17] G.A. Bain, J.F. Berry, J. Chem. Edu. 5 (2008) 532.
[18] T.-F. Wang, C.-L. Lin, C.-N. Chen, T.-C. Wang, J. Chin. Chem. Soc. 54 (2007) 811.
[19] S.H. Chanteau, J.M. Tour, J. Org. Chem. 68 (2003) 8750.
[20] D.R. Coulson, L.C. Satek, S.O. Grim, in: F.A. Cotton (Ed.), Inorganic Syntheses,
John Wiley & Sons, Inc., 1972, pp. 121e124.
[21] Agilent, CrysAlis Pro, Agilent Technologies, Yarnton, Oxfordshire, England,
2011.
[22] G.M. Sheldrick, Acta Crystallogr. Sect. A 46 (1990) 467.
[23] G.M. Sheldrick, SHELXL-97, Program for the Refinement of Crystal Structures,
University of Gottingen, Gottingen, Germany, 1997.
[24] B.V. Nonius, “Collect” Data Collection Software, 1998.
[25] Z. Otwinowski, W. Minor, Processing of X-ray Diffraction Data Collected in
Oscillation Mode, in: C.W. Carter Jr., R.M. Sweet (Eds.), Methods in Enzy-
mology, Macromolecular Crystallography, Part A, vol. 276, Academic Press,
1997, pp. 307e326.
€
€
[26] Y. Zhao, D.G. Truhlar, J. Chem. Phys. 125 (2006) 194101.
[27] (a) W.J. Hehre, J.A. Pople, J. Am. Chem. Soc. 94 (1972) 6901;
(b) A.D. McLean, G.S. Chandler, J. Chem. Phys. 72 (1980) 5639;
(c) R. Krishman, J.S. Binkley, R. Seeger, J.A. Pople, J. Chem. Phys. 72 (1980) 650.
[28] D. Rappoport, F. Furche, J. Chem. Phys. 133 (2010) 134105.
[29] X. Xu, D.G. Truhlar, J. Chem. Theory Comput. 8 (2012) 80.
[30] (a) D. Feller, J. Comp. Chem. 17 (1996) 1571;
Acknowledgment
The authors thank National Science Centre for financial support
of this work (Grant DEC-2011/01/B/ST5/06297). Calculations were
done in Interdisciplinary Centre for Mathematical and Computa-
tional Modelling (grant no.G53-27).
(b) K.L. Schuchardt, B.T. Didier, T. Elsethagen, L. Sun, V. Gurumoorthi, J. Chase,
J. Li, T.L. Windus, J. Chem. Inf. Model 47 (2007) 1045.
[31] (a) V. Barone, M. Cossi, J. Phys. Chem. A 102 (1998) 1995;
(b) M. Cossi, N. Rega, G. Scalmani, V. Barone, J. Comp. Chem. 24 (2003) 669;
(c) G. Scalmani, M.J. Frisch, J. Chem. Phys. 132 (2010) 114110;
(d) E. Canses, B. Mennucci, J. Tomasi, J. Chem. Phys. 107 (1997) 3032;
(e) J. Tomasi, M. Persico, Chem. Rev. 94 (1994) 2027;
(f) J. Tomasi, B. Mennucci, R. Camm, Chem. Rev. 105 (2005) 2999.
[32] G.B. Bacskay, Chem. Phys. 61 (1981) 385.
[33] Y. Qu, Spectrochim. Acta Part A 94 (2012) 205.
Appendix A. Supplementary material
CCDC 1038322 contains the supplementary crystallographic
data for this paper. These data can be obtained free of charge from
The Cambridge Crystallographic Data centre via www.ccdc.cam.ac.
uk/data_request/cif.
[34] Gaussian 09, Revision D.01 M.J. Frisch, G.W. Trucks, H.B. Schlegel,
G.E. Scuseria, M.A. Robb, J.R. Cheeseman, G. Scalmani, V. Barone, B. Mennucci,
G.A. Petersson, H. Nakatsuji, M. Caricato, X. Li, H.P. Hratchian, A.F. Izmaylov,
J. Bloino, G. Zheng, J.L. Sonnenberg, M. Hada, M. Ehara, K. Toyota, R. Fukuda,
J. Hasegawa, M. Ishida, T. Nakajima, Y. Honda, O. Kitao, H. Nakai, T. Vreven,
J.A. Montgomery Jr., J.E. Peralta, F. Ogliaro, M. Bearpark, J.J. Heyd, E. Brothers,
K.N. Kudin, V.N. Staroverov, T. Keith, R. Kobayashi, J. Normand,
K. Raghavachari, A. Rendell, J.C. Burant, S.S. Iyengar, J. Tomasi, M. Cossi,
N. Rega, J.M. Millam, M. Klene, J.E. Knox, J.B. Cross, V. Bakken, C. Adamo,
J. Jaramillo, R. Gomperts, R.E. Stratmann, O. Yazyev, A.J. Austin, R. Cammi,
C. Pomelli, J.W. Ochterski, R.L. Martin, K. Morokuma, V.G. Zakrzewski,
G.A. Voth, P. Salvador, J.J. Dannenberg, S. Dapprich, A.D. Daniels, O. Farkas,
J.B. Foresman, J.V. Ortiz, J. Cioslowski, D.J. Fox, Gaussian, Inc., Wallingford CT,
2013.
Appendix BSupplementary data
Supplementary data related to this article can be found at http://
dx.doi.org/10.1016/j.jorganchem.2015.04.037.
References
[1] See for example: (a) W.J. Grisby, P.P. Power, J. Am. Chem. Soc. 118 (1996)
7981;
(b) R.J. Wehmschulte, M.A. Khan, B. Twamley, B. Schiemenz, Organometallics
20 (2001) 844;