Di- and trinuclear zirconium complexes as catalysts for ethylene polymerization

Article abstract of DOI:10.1016/j.jorganchem.2016.07.018

Bimodal and multimodal molecular weight distributions of polyethylenes can be achieved with di- or trinuclear zirconium catalysts in homogeneous solution. In order to prepare such complexes, bis(phenoxyimine) zirconium complexes and zirconocene complexes were coupled in Sonogashira reactions. Hydrosilylation reactions were applied for the combination of metallocene complexes with silane substituted N-heterocyclic compounds, such as 3,5-dimethylpyrazoles. The resulting di- and trinuclear complexes were activated with methylaluminoxane (MAO) and applied as catalysts for ethylene polymerization. The catalytic performances of these complexes and their applications in olefin polymerization reactions are discussed.

Full text of DOI:10.1016/j.jorganchem.2016.07.018

Journal of Organometallic Chemistry 820 (2016) 30e40
Contents lists available at ScienceDirect
Journal of Organometallic Chemistry
journal homepage: www.elsevier.com/locate/jorganchem
Di- and trinuclear zirconium complexes as catalysts for ethylene
polymerization
Andrea M. Rimkus, Helmut G. Alt*
€
Universitat Bayreuth, Laboratorium für Anorganische Chemie, 95440 Bayreuth, Germany
a r t i c l e i n f o
a b s t r a c t
Article history:
Bimodal and multimodal molecular weight distributions of polyethylenes can be achieved with di- or
trinuclear zirconium catalysts in homogeneous solution. In order to prepare such complexes, bis(phe-
noxyimine) zirconium complexes and zirconocene complexes were coupled in Sonogashira reactions.
Hydrosilylation reactions were applied for the combination of metallocene complexes with silane
substituted N-heterocyclic compounds, such as 3,5-dimethylpyrazoles. The resulting di- and trinuclear
complexes were activated with methylaluminoxane (MAO) and applied as catalysts for ethylene poly-
merization. The catalytic performances of these complexes and their applications in olefin polymeriza-
tion reactions are discussed.
Received 19 January 2016
Received in revised form
23 July 2016
Accepted 29 July 2016
Available online 30 July 2016
Dedicated to Professor Max Herberhold on
the occasion of his 80th birthday (August
02, 2016).
© 2016 Elsevier B.V. All rights reserved.
Keywords:
Di-and trinuclear zirconium complexes
Coupling reactions
Catalytic ethylene polymerization
Multimodal molecular weight distributions
1. Introduction
multinuclear complexes where the metal centers are far enough
away from each other. In the literature only a few examples for
One of the most intriguing properties of mono- and dinuclear
homogeneous olefin polymerization catalysts is the fact that tiny
differences in the molecular structure of the catalyst precursors can
have a tremendous influence on their performances [1e10]. This is
the main reason for the preparation of thousands of such com-
plexes to study structure-property-relationships empirically and to
prepare tailored polyolefins [11e15]. Polyolefins with a broad or
bimodal molecular weight distribution (MWD) show an advanta-
geous processability and therefore it is very attractive to prepare
catalysts that are able to produce polyolefins with a desired mo-
lecular weight distribution. Attempts to obtain bimodal molecular
weight distributions of polyethylenes by mixing mononuclear
di(arylimino)pyridine iron complexes and metallocene complexes
in homogeneous and heterogeneous systems failed in most cases
because of averaging effects of different active sites leading to
balanced molecular weights of the resulting polymer [16e18]. In
order to avoid uncontrolled interactions of different active sites,
different metal centers must be held at a certain distance to each
other. A concept to reach this goal is the synthesis of di- or
multinuclear polymerization catalysts are known [19e25]. Since
there exists a pool of more than 1500 mononuclear complexes as
potential catalyst precursors in our research group, we had excel-
lent starting conditions for this project. We picked metallocene
complexes [26e29] as promising candidates for high molecular
weight polymers and bis(phenoxyimine) [30e36],
a-di(imine)
[37e43] and 2,6-bis(arylimino)pyridine [44e48] complexes for
polymers with low molecular weights Scheme 1.
The best way to couple these complexes depends on the com-
plex type. Complex types with different metal centers, i.e. metal-
locene zirconium complexes and a-di(imine) chromium complexes
need to be combined after the metal centers are introduced. Donor/
acceptor interactions are also a suitable synthesis pathway. For
complexes with the same metal center like metallocene zirconium
complexes and bis(phenoxyimine) zirconium complexes, CeC
coupling reactions can be performed before the complexation is
carried out. The combination of phenoxyimine complexes and
metallocene complexes works with palladium catalysed Sonoga-
shira reactions [49,50].
Another method for combining ligand precursors are hydro-
silylation reactions. Silicon compounds with a silicon-hydrogen
* Corresponding author.
E-mail address: helmut.alt@uni-bayreuth.de (H.G. Alt).
bond and
u-alkenyl substituted ligand precursors are required.
http://dx.doi.org/10.1016/j.jorganchem.2016.07.018
0022-328X/© 2016 Elsevier B.V. All rights reserved.

A.M. Rimkus, H.G. Alt / Journal of Organometallic Chemistry 820 (2016) 30e40
31
Scheme 1. Some complexes suitable for combination reactions: Metallocene complexes, bis(phenoxyimine complexes, 2,6-bis(arylimino)pyridine complexes,
a-di(imine)
complexes.
The reaction is catalysed by hexachloro platinum acid. In the
literature, coupled binuclear metallocene complexes are described
[19,20,51,52] as well as amido functionalized half sandwich com-
plexes [53,54]. The idea is to mix these complex types and func-
tionalize metallocene ligand precursors with amino groups by
hydrosilylation reactions Scheme 2.
Scheme 3. Synthesis of substituted salicylaldehydes.
2. Results and discussion
products.
2.1. Coupling of phenoxyimine ligand precursors and metallocene
type ligand precursors using Sonogashira reactions
As starting material either compound 1 or 2 can be used since
the iodo substituent can be located either in the 5-position of the
salicylaldehyde or anywhere in the used amine Scheme 5.
The preparation of the phenoxyimine part requires two,
respectively three steps depending where the iodo substituent is
introduced.
2.1.1. Synthesis of substituted salicylaldehydes
To obtain 3-substituted salicylaldehydes, phenols containing
one unsubstituted ortho-position, are deprotonated in tetrahy-
drofuran with a Grignard reagent. The following reaction with para
formaldehyde in toluene and subsequent acidic hydrolysis leads to
salicylaldehydes Scheme 3 [34].
2.1.4. Synthesis of
derivatives
u-alkenyl and u-alkynyl substituted indenyl
The synthesis of
compounds is carried out in toluene at room temperature adding
-alkynyl bromides to indenyl lithium Scheme 6.
These compounds could be used for the next reaction without
u-alkynyl and u-alkenyl substituted indenyl
2.1.2. Introduction of iodo substituents
For introducing an iodine substituent in the para-position to the
hydroxyl group, 3-tert-butylsalicylaldehyde is treated with ben-
zyltrimethylammonium dichloroiodate in methanol/dichloro-
methane to give 3-tert-butyl-5-iodo-salicylaldehyde Scheme 4 [55].
u
further purification.
2.1.5. Synthesis of fulvene derivatives
2.1.3. Synthesis of phenoxyimine compounds
The synthesis of phenoxyimine compounds was achieved
following two different routes:
Fulvene derivatives can be obtained by base catalysed conden-
sation reactions of indenes and ketones [57,58] The substituted
indenyl derivatives were dissolved in methanol. The addition of a
ketone and pyrrolidine as a base to the reaction mixture resulted in
3-substituted fulvene derivatives Scheme 7.
a) The condensation reaction of a substituted salicylaldehyde with
an aliphatic or aromatic amine in toluene at reflux temperatures
gives the phenoxyimine compound under azeotropic water
separation [56].
b) The substituted salicylaldehyde is reacted with a small excess of
an aliphatic or aromatic amine in the presence of molecular
sieves (3 Å) in toluene at room temperature.
2.1.6. C1-bridged ligand precursors containing an
alkenyl substituent
The synthesis of C1-bridged ligand precursors follows the ful-
vene method [59,60]. This method makes use of the fact that flu-
orenyl or indenyl anions can act as nucleophils and add to exocyclic
double bonds. An anion is formed that gives the C1-bridged ligand
u-alkynyl or u-
The second method is milder and produces less undesired side
Scheme 2. Amido functionalized half sandwich complexes, binuclear silicon bridged metallocene complexes and the combination of both types.

32
A.M. Rimkus, H.G. Alt / Journal of Organometallic Chemistry 820 (2016) 30e40
Scheme 4. Synthesis of 3-tert-butyl-5-iodosalicylaldehyde 2.
Scheme 5. Synthesis of phenoxyimine compounds [56].
the u-alkynyl substituent is located at the 3-position of the indene.
2.1.7. Combination of phenoxyimine and metallocene ligand
precursors using Sonogashira reactions
The iodinated phenoxyimine compound 3 and the
u-alkynyl
5 ( R1 =
)
6 ( R1 =
) [26]
substituted metallocene ligand precursor 9 were treated with
bis(triphenylphosphine)palladium dichloride, copper iodide and
triethylamine to obtain the target compound 11 Scheme 9.
Compound 12 was obtained in the same way from the phe-
Scheme 6. Synthesis of
u-alkynyl and
u
-alkenyl substituted indenyl compounds.
noxyimine compound 4 and the
ligand precursor 9 Scheme 10.
u-alkynyl substituted metallocene
2.1.8. Synthesis of the phenoxyimine complexes 13 and 14
The phenoxyimine compounds were deprotonated with sodium
7 ( R1 =
8 ( R1 =
)
)
Scheme 7. Synthesis of fulvene derivatives.
precursor after hydrolysis Scheme 8.
Metallocene ligand precursors can be obtained in a two step
reaction, if the
u-alkynyl substituent is located in the bridge and
therefore introduced by the ketone, and in a three step reaction, if
9 ( R1 =
)
10[44] ( R1 =
)
Scheme 8. Synthesis of C1-bridged ligand precursors [61].
Scheme 9. Synthesis of the coupled ligand precursor 11.

A.M. Rimkus, H.G. Alt / Journal of Organometallic Chemistry 820 (2016) 30e40
33
Table 1
Ethylene polymerization reactions with complexes 13e16, A and B. Polymerization
conditions: solvent: 250 ml n-pentane, activator: MAO, Zr:Al 1:500, 35 ꢀC, 10 bar
ethylene, 1 h.
Complex
activity [kg PE/mol Zr $ h]
M
n [g/mol]
Mw [g/mol]
PD
13
14
15
16
A
8320
15600
2306
e
7260
3370
7539
e
41700
9500
306772
e
5.74
2.83
40.69
e
5630
2840
9640
2915
702550
125600
72.9
43.1
Scheme 10. Ligand precursor 12.
B
hydride in tetrahydrofuran and treated with zirconium tetrachlo-
ride Scheme 11 [62].
2.3. Activation and deactivation of bis(phenoxyimine)zirconium
complexes
Bis(phenoxyimine) zirconium complexes have a specific feature
after activation with aluminoxanes. They are only active, when the
activation with MAO occurs under an ethylene atmosphere. If this is
not the case, one of the two phenoxyimine ligands migrates to an
aluminum center, blocks it and deactivates the polymerization
ability of its own complex Scheme 15 [46].
2.1.9. Synthesis of the trinuclear complexes 15 and 16 from the
coupling products
To obtain complexes from the coupling products 11 and 12, the
latter were deprotonated with sodium hydride in tetrahydrofuran
and then treated with zirconium tetrachloride. The ratio of the
reactants was 2:6:3. The obtained complexes 15 and 16 contain
metals in two different coordination spheres. In both metallocene
fragments, zirconium is coordinated tetrahedrally, in the central
phenoxyimine moiety it can be described as octahedrally distorted.
2.3.1. Comparison of the polymerization activities of the trinuclear
complexes 13, 15 and A and 14, 16, B
The synthesised trinuclear phenoxyimine zirconocene com-
plexes 13, 14 and 15 were active in homogeneous ethylene poly-
merization; complex 16 showed no activity.
2.2. Ethylene polymerization reactions with the complexes 13e16,
A and B
Better results were obtained, when the triple bond is not
directly connected to the phenoxyimine unit through the indenyl
ring but through the bridging unit. It is obvious that bigger sub-
stituents in para-position of the former aniline ring unit have a
negative influence on the polymerization activities. Complex 13,
with an iodo substituent, has the highest activity, complex 15,
where the triple bond is connected to the phenoxyimine unit
through the indenyl ring, shows the lowest activity. Complex A,
with the triple bond connected to the phenoxyimine unit through
its bridging unit, has an average activity compared with the others
Scheme 16.
The synthesised phenoxyimine zirconocene complex 12 was
tested in homogeneous ethylene polymerization experiments.
Methylaluminoxane was used as cocatalyst (Zr:Al ratio ¼ 1:500). All
polymerization experiments were carried out under an ethylene
pressure of 10 bar for 1 h, at a temperature of 35 ꢀC, in pentane
solution.
The activities of complex 13e16 together with the GPC profiles
of the resulting PE (polydispersity PD ¼ Mw/Mn, molecular weights
Mn and Mw) are summarised in Table 1.
For comparison purposes the already known complexes A and B
[56] (Schemes 12e14) are included.
Bigger substituents in the para-position to the former hydroxy
group show the same effect as bigger substituents in para-position
of the former aniline ring unit. Here the influence on the activity is
even more noticeable. Complex 15 with an iodo substituent in that
position has a high activity in ethylene polymerization. The activity
of complex B, where the triple bond is connected to the phenox-
yimine unit through its bridging unit, is around 80% lower and
complex 16, where the triple bond is connected to the phenox-
yimine unit through the indenyl ring, is inactive Scheme 17.
2.4. Discussion of the GPC profile of polyethylene obtained with
complex 15/MAO
The multimodality of the polymer is shown in Scheme 18. The
left part of the GPC spectrum shows the molecular weight distri-
bution of the polymer that was produced with the phenoxyimine
unit. The higher molecular weight part is smaller and can be
assigned to the polymer produced with the metallocene unit. The
metallocene centers are generally not so active at 35 ꢀC and pro-
duce different active centers during the polymerization process,
leading to a distinctively broader molecular weight distribution.
starting compound R1
R2
product
13
3
4
H
H
4-iodophenyl
cyclopentyl
14
Scheme 11. Synthesis of bis(phenoxyimine) zirconium complexes [56].

34
A.M. Rimkus, H.G. Alt / Journal of Organometallic Chemistry 820 (2016) 30e40
Scheme 12. Synthesis of the trinuclear phenoxyimine zirconium complex 15.
Scheme 13. The trinuclear phenoxyimine zirconium complex 16.
2.5. Hydrosilylation reactions to couple different types of ligand
precursors
catalyst, solid hexachloroplatinum acid was used. Experiments
with hexachloroplatinum acid hexahydrate as an aqueous solution
failed because of hydrolysis reactions Scheme 19.
2.5.1. Hydrosilylation reactions with the
metallocene ligand precursor 10 and di(chloro)methylsilane
The metallocene ligand precursor 10 contains an
substituent and therefore it can be used in hydrosilylation re-
actions. To the -alkenyl substituted compound di(chloro)meth-
ylsilane, dissolved in a small amount of n-pentane, is added. As a
u
-alkenyl substituted
Furthermore it proved useful for this ligand precursor to couple
first the metallocene ligand precursors with the chloro silane de-
rivatives, and then substitute the chloro atoms. When already
substituted silane derivatives were coupled with metallocene
ligand precursors only side products and unreacted educts were
obtained.
u
-alkenyl
u

A.M. Rimkus, H.G. Alt / Journal of Organometallic Chemistry 820 (2016) 30e40
35
Scheme 14. Complexes A and B [56].
Scheme 15. Activation and deactivation of bis(phenoxyimine) zirconium complexes [46].
8320
18000
activity [kg PE / mol Kat. • h]
9000
8000
7000
6000
5000
4000
3000
2000
1000
0
15600
activity [kg PE / mol Kat. • h]
16000
14000
12000
10000
8000
6000
4000
2000
0
5630
2306
2840
0
13
15
A
14
16
B
Scheme 16. Activities of the phenoxyimine complex 13 [56] and the phenoxyimine
zirconocene complexes 15 and A [56]. Polymerization conditions: 10 bar ethylene,
35 ꢀC, 1 h, cocatalyst: MAO, Zr: Al ¼ 1: 500, n-pentane.
Scheme 17. Activities of the phenoxyimine complex 14 [56] and the phenoxyimine
zirconocene complexes 16 and B [56]. Polymerization conditions: 10 bar ethylene,
35 ꢀC, 1 h, cocatalyst: MAO, Zr:Al ¼ 1:500, n-pentane.
2.5.2. Synthesis of amino functionalized, hydrosilylated metallocene
ligand precursors
atoms, is analogous to cyclopentadiene and offers its use for this
application. The hydrogen atom on one of the two nitrogen atoms
can be easily substituted. In the literature, bis- and tris-(3,5-
dimethylpyrazolyl)silane derivatives are described together with
their corresponding neutral metal complexes [63,64]. No deproto-
nation step is necessary for the complexation reactions.
Chlorosilanes can be easily reacted with amines [53]. This re-
action was used to gain a second possible coordination site. Inter-
esting systems for this reaction are bis- or tris-(3,5-
dimethylpyrazolyl)silane derivatives. Pyrazole, a five membered
ring, where two vicinal carbon atoms are substituted by nitrogen
Compound 17 was treated with 3,5-dimethylpyrazole in

36
A.M. Rimkus, H.G. Alt / Journal of Organometallic Chemistry 820 (2016) 30e40
Scheme 18. GPC profile of the polyethylene produced with the trinuclear complex 15/MAO.
Scheme 19. Hydrosilylation reactions of the metallocene ligand precursor 10 with di(chloro)methyl-silanes.
dichloromethane using triethylamine as a base Scheme 20.
their nitrogen atoms, two equivalents of zirconium tetrachloride
were used Scheme 21.
2.5.3. Synthesis of the binuclear complex 19
The ligand precursor 18 was deprotonated with 2 equivalents of
n-butyllithium at ꢁ78 ꢀC. Addition of two equivalents of zirconium
tetrachloride resulted in the formation of complex 19. For a
deprotonation of the indenyl and fluorenyl unit two equivalents of
n-butyl lithium are needed. The subsequent reaction with one
equivalent of the metal salt gives the complex. Since both neutral
pyrazolyl units are prone to coordinate to a zirconium atom via
2.6. Ethylene polymerization with complex 19
Complex 19 was tested in homogeneous ethylene polymeriza-
tion experiments. Methylaluminoxane was used as cocatalyst (Zr:Al
ratio ¼ 1:2500). The polymerization experiment was carried out
under an ethylene pressure of 10 bar for 1 h at a temperature of
60 ꢀC. As a solvent, n-pentane was used. The activity of complex 19
Scheme 20. Reaction of the hydrosilylated compound 17 with pyrazolyl derivatives.

A.M. Rimkus, H.G. Alt / Journal of Organometallic Chemistry 820 (2016) 30e40
37
Scheme 21. Synthesis of complex 19.
in homogeneous ethylene polymerization was 159 kg PE/mol Zr $ h.
Obviously, the pyrazolyl complex is no suitable counterpart for the
metallocene complex. The hydrosilylation reaction shown here is
still an easy way to couple different ligand types. They can be for
example used for coupling silicon bridged metallocene complexes
for CD2Cl2;
d
¼ 128.0 ppm for C6D6).
4.2. GC/MS spectroscopy
GC/MS spectra were recorded with a Thermo Focus gas chro-
matograph in combination with a Thermo DSQ mass detector. A
30 m HP-5MS fused silica column (film 0.25 mm, flow 75 ml/min,
with
a-diimine complexes with terminal double bonds, forming
dinuclear complexes with good activities [65].
split ratio 50:1), helium (4.6) was applied as the carrier gas. Using a
30 m column, the routinely performed temperature program star-
ted at 50 ꢀC (2 min). After a heating phase of 24 min (10 K/min, final
temperature 290 ꢀC) the end temperature was held for 15 min
(plateau phase).
At the Zentrale Analytik of the University of Bayreuth GC/MS
spectra were routinely recorded with a HP5890 gas chromatograph
in combination with MAT 95 mass detector.
3. Conclusions
Di- and trinuclear complexes can be used to obtain polymers
with multimodal molecular weight distributions. The different
metal centers from the combined complexes represent different
active sites and they produce different polymer types in one reac-
tion. The challenge is to find suitable complexes for combinations
that share the same polymerization conditions (i.e. highest activity
at the same temperature), use the same central metal and give
polymers with the desired GPC profiles. Dinuclear complexes from
the coupling of bis(phenoxyimine) zirconium complexes and
metallocene complexes produce polymers with a high molecular
weight portion (metallocene moiety) and a low molecular weight
portion bis(phenoxyimine moiety). A disadvantage is the fact that
metallocene complexes display their highest activities around
60 ꢀC, bis(phenoxyimine) complexes at 35 ꢀC. Metallocene com-
plexes are best activated with an Al:Zr ratio of 1:2500, bis(phe-
noxyimine) complexes with a ratio of 1:500. The combined
complexes cannot maximize their full potential. Polymerization
temperatures above 35 ꢀC cannot be applied, because ligand
transfer reactions from bis(phenoxyimine) complexes to the
aluminum centers of MAO occur faster at elevated temperatures,
and the activity of the metallocene part is reduced. Another prob-
lem is the high synthesis effort. The synthesis of a mononuclear
complex contains at an average two to four steps. When preparing
multinuclear complexes, the total number of reaction steps can be
six to ten. The herein tested pyrazolyl complex is not a suitable
counterpart for the metallocene complex and for ethylene poly-
merization reactions. Obviously the nitrogen heteroatoms are not
sufficiently shielded in order to avoid interactions with the Lewis
acidic zirconium atoms of neighboured molecules.
4.3. Mass spectrometry
Mass spectra were routinely recorded at the Zentrale Analytik of
the University of Bayreuth with a VARIAN MAT CH-7 instrument
(direct inlet, EI, E ¼ 70 EV) and a VARIAN MAT 8500 spectrometer.
4.4. Elemental analysis
The analyses were performed with a VarioEI III CHN instrument.
Therefore, 4e6 mg of the complex was weighed into a standard tin
pan. The tin pan was carefully closed and introduced into the auto
sampler of the instrument. The raw values of the carbon, hydrogen
and nitrogen contents were multiplied with calibration factors
(calibration compound: acetamide).
4.5. Differential scanning calorimetry (DSC)
The thermal attributes of the polymer samples were examined
in a Diamond DSC instrument (Perkin-Elmer). After drying the
polymer samples, 4e7 mg of the polymer was weighed into a
standard aluminum pan. The sealed pan was then introduced into
the instrument. The measurements were performed with the
following temperature program:
4. Experimental
1. heating phase (10 K/min) from 50 ꢀC to 160 ꢀC; 1. cooling phase
ꢀ
(ꢁ10 K/min) to 50 C.
4.1. NMR spectroscopy
2. heating phase (10 K/min) from 50 ꢀC to 160 ꢀC; 2. cooling phase
ꢀ
(ꢁ10 K/min) to 50 C.
The spectrometers Bruker ARX 250 and Varian (Inova 400) were
available for the recording of NMR spectra. The samples were
prepared under inert atmosphere (argon) and routinely recorded at
25 ꢀC. The chemical shifts in the 1H NMR spectra are referred to the
The temperature was corrected linearly to indium
(mp ¼ 156.6 ꢀC), for calibration the melting enthalpy of indium was
used (
D
Hm ¼ 28,45 J/g).
residual proton signal of the solvent (
d
¼ 7.24 ppm for CDCl3;
For polyethylene, the maxima of the second heating cycle were
used. For the calculation of the crystallinity, the correlation
d
¼ 5.32 ppm for CD2Cl2,
d
¼ 7.15 ppm for C6D6) and in 13C NMR
spectra to the solvent signal (
d
¼ 77.0 ppm for CDCl3;
d
¼ 53.5 ppm
a
¼
DHm=D DHm was obtained from the second
Hm0 was used.

38
A.M. Rimkus, H.G. Alt / Journal of Organometallic Chemistry 820 (2016) 30e40
heating cycle of the DSC, for
olated for 100% crystalline polyethylene a value of 290 J/g [66] was
used.
D
Hm0 as the melting enthalpy extrap-
(Cq), 137.4, 137.4 (AreCH), 121.2 (Cq), 79.5 (CeI), 70.4 (CH), 35.5 (Cq),
35.2 (2C) (CH2), 29.6 (tBueCH3), 25.0 (2C) (CH2). MS m/z: 371 Mþ
(100), 356 M e Me (81), 328 M e C3H7 (87), 244 M e I (6).
4.6. Synthesis procedures
4.6.4. General synthesis of the 1-substituted indenyl compounds 5
and 6
4.6.1. Synthesis of 3-tert-butyl-salicylaldehyde (1)
Indenyl lithium (27.93 mmol) was dissolved in toluene. Then an
alkenyl or alkynyl bromide (27.93 mmol) was added and the reac-
tion mixture was stirred at room temperature over night. The so-
lution was filtered over sodium sulphate and the solvent removed
in vacuum to give the products as yellow oils. Yields: 90e99%.
To 2-tert-butylphenol (50 mmol), dissolved in tetrahydrofuran
(40 ml), methylmagnesium bromide (55.5 mmol, 3 M in diethyl
ether) was added. After stirring for 2 h at room temperature the gas
production ended and 90% of the solvent was removed in vacuo.
Then toluene (100 ml), triethylamine (72 mmol) and para-
formaldehyde (125 mmol) were added. The reaction mixture was
stirred for 2 h at 88 ꢀC. After cooling down to room temperature, the
yellow fluorescent solution was hydrolysed with cold hydrochloric
acid (250 ml, 1 M in water). The organic phase was removed and
dried over sodium sulphate. The solvent was evaporated and 3-tert-
butylaldehyde was obtained from high vacuum distillation. Yield:
85%.
5
1H NMR: 7.81e7.88 m (1H, AreH), 7.52e7.71 m (3H, AreH),
7.13e7.17 m (1H, AreH), 6.87e6.93 m (1H, AreH), 3.90 dt (1H, Ind-
H1), 2.83e2.96 m (1H, CH2), 2.53e2.68 m (1H, CH2), 2.40 t (1H,
^CH). 13C NMR: 146.6, 144.6 (Cq), 138.7, 132.2, 127.6, 125.5, 123.6,
121.7 (AreCH), 83.2 (Cq, C^C), 70,2 (^CH), 49.2 (CH, Ind-C1), 21.4
(CH2). MS m/z: 154 Mþ (47), 115 M e propynyl (100).
6
1H NMR: 7.23e7.35 m (2H, AreH), 7.05e7.20 m (2H, AreH),
6.71 d (1H, AreH), 6.44 d (1H, AreH), 5.66e5.84 m (1H, CH]CH2),
4.86e5.02 m (2H, ]CH2), 3.35e3.43 s (1H, Ind-H1), 1.99e2.12 m
(2H, CH2), 1.85e1.98 m (1H, CH2), 1.43e1.61 m (1H, CH2). 13C NMR:
147.6, 144.3 (Cq), 138.9 (CH]), 138.5, 131.0, 126.4, 124.7, 122.8, 121.0
(AreCH), 114.8 (]CH2), 49.8 (CH, Ind-C1), 31.6, 30.6 (CH2).
1H NMR: 11.84 s (1H, OH), 9.72 s (1H, O]CeH), 7.43e7.47 m (1H,
AreH), 7.25e7.29 m (1H, AreH), 6.86 t (1H, AreH), 1.38 s (9H,
tBueCH3). 13C NMR: 197.2 (O]CeH), 161.1, 138.0, 120.7 (Cq), 134.1,
132.0, 119.3 (AreCH), 34.8 (Cq), 29.2 (tBueCH3). MS m/z: 178 Mþ
(26), 163 M e Me (100), 135 M e C3H7 (39).
4.6.5. General synthesis of the fulvene derivatives 7 and 8
4.6.2. General synthesis route for the iodination of 3-tert-butyl-
salicylaldehyde derivative (2)
An indenyl derivative (62.66 mmol) and pyrrolidine
(37.60 mmol) were dissolved in methanol (120 ml). Acetone (80.00
p) was then slowly added and the reaction mixture was stirred at
room temperature for two days. After that glacial acetic acid
(50.13 mmol), water (25 ml) and n-pentane (25 ml) were slowly
added. The organic layer was washed with water twice, then dried
over sodium sulphate and filtered over silica. Yields: 50e80%.
3-tert-Butyl-salicylaldehyde or its derivatives (8.21 mmol) was
dissolved in a mixture of methanol and dichloromethane (100 ml,
ratio: 3:7). Then, benzyltrimethylammonium dichloroiodate
(8.98 mmol) and anhydrous calcium carbonate (10.76 mmol) were
added. The reaction mixture was stirred for one day at room tem-
perature. After that, the excess calcium carbonate was filtered off.
The filtrate was evaporated to 20% and a 5% solution of sodium
hydrogen sulphite (20 ml) in water was added for decomposition of
the excess benzyltrimethylammonium dichloroiodate. The organic
phase was extracted with diethyl ether and dried over sodium
sulphate. The solvent was removed in vacuo and the product was
crystallized from n-pentane. Yield: 59e92%.
7
1H NMR: 7.80e7.88 m (1H, AreH), 7.43e7.47 m (1H, AreH),
7.34e7.40 m (2H, AreH), 6.95e6.97 m (1H, AreH), 3.52e3.56 m
(1H, CH2), 3.40e3.44 m (1H, CH2), 2.44 s (3H, CH3), 2.33 s (3H,
^CH), 2.25 s (1H, CH3). 13C NMR: 142.9, 141.9, 136.8, 135.6, 135.5
(Cq), 130.0, 126.0, 125.3, 123.6, 118.7 (1H, AreCH), 81.3 (Cq, C^C),
70.6 (^CH), 37.7 (CH2), 27.6, 22.8 (CH3). MS m/z: 194 Mþ (88),179 M
e Me (100), 152 M e C3H6 (28).
2
1H NMR: 11.82 s (1H, OH), 9.85 s (1H, O]CeH), 7.52 d (1H,
8 1H NMR: 7.78 d (1H, AreH), 7.36 d (1H, AreH), 7.27 quin (2H,
AreH), 6.63 s (1H, AreH), 5.95e6.06 m (1H, CH]), 5.05e5.21 m
(2H, ]CH2), 2.69e2.77 m (2H, CH2), 2.49e2.56 m (2H, CH2), 2.43 s
(3H, CH3), 2.29 s (3H, CH3).
AreH), 7.38 d (1H, AreH), 1.42 s (9H, tBueCH3). 13C NMR: 197.1 (O]
CeH), 161.2, 138.2, 120.6 (Cq), 134.1, 132.0 (AreCH), 74.7 (Cq, CeI),
34.8 (Cq), 29.2 (tBueCH3). MS m/z: 304 Mþ (65), 289 M e Me (100),
261 M e C3H7 (40).
4.6.6. General synthesis for the C1-bridged indenyl fluorenyl
compounds 9 and 10
4.6.3. General synthesis route for phenoxyimine compounds 3 and
4
To fluorene (50 mmol), dissolved in diethyl ether (100 ml), n-
butyl lithium (50 mmol, 1.6 M in hexane) was slowly added at room
temperature. The reaction mixture was stirred at room tempera-
ture for 8 h. Then the equimolar amount of a fulvene derivative was
added slowly. The mixture was stirred another 16 h at room tem-
perature and hydrolysed with water afterwards. The organic layer
was dried over sodium sulphate and the solvent was removed in
vacuo. The residue was dissolved in n-pentane, filtered over silica
and crystallized at ꢁ25 ꢀC. Yields: 30e50%.
A salicylaldehyde derivative (1.7 mmol) was dissolved in toluene
(70 ml). After addition of a substituted amine respectively aniline
(2.04 mmol) and a catalytic amount of para-toluene sulfonic acid,
the reaction mixture was stirred for 3 h under reflux using a Dean-
Stark trap. After cooling down to room temperature, the reaction
mixture was filtered over sodium sulphate and silica. The solvent
was evaporated to 1e2 ml followed by crystallization from ethanol.
Yield: 84e90%.
3
1H NMR: 13.67 s (br, 1H, OH), 8.58 s (1H, N]CeH),
7.70e7.73 m (2H, AreH), 7.39 dd (1H, AreH), 7.23 dd (1H, AreH),
7.01e7.04 m (2H, AreH), 6.87 t (1H, AreH), 1.45 s (9H, tBueCH3). 13
9
1H NMR: 7.88 d (1H, AreH), 7.77 d (1H, AreH), 7.10e7.56 m
(9H, AreH), 6.84e6.86 m (1H, AreH), 6.14 d (1H, AreH), 4.77 s (1H,
Flu-H9), 3.90 s (1H, Ind-H1), 2.67e2.79 m (1H, CH2), 2.37e2.49 m
(1H, CH2), 2.08 t (1H, ^CH), 1.29 s (br, 6H, CH3). 13C NMR: 151.7,
148.0 (2C), 145.1 (2C), 143.4, 142.1 (Cq), 132.6, 127.0, 126.9, 126.7,
126.4, 126.1, 126.0, 125.9, 125.0, 123.8, 122.5, 119.9, 119.4 (AreCH),
83.0 (Cq, C^C), 69.3 (^CH), 53.3 (CH, Flu-C9), 46.8 (CH, Ind-C1),
40.2 (Cq), 36.9 (CH2). MS m/z: 360 Mþ (3), 207 M e 5 (33), 195 M e
Flu (55), 165 M e 7 (100).
C
NMR: 163.7 (N]CeH), 160.5, 148.1, 137.7, 118.9, 91.3 (Cq), 138.4,
130.8, 130.7 (2C), 123.2, 118.5 (2C) (AreCH), 34.9 (Cq), 293
(tBueCH3). MS m/z: 379 Mþ (66), 364 M e Me (100), 336 M e C3H7
(79).
4
1H NMR: 14.23 s (1H, OH), 8.22 s (1H, N]CeH), 7.48 d (1H,
AreH), 7.36 d (1H, AreH), 3.74 quin (1H, NeCH), 1.60e2.00 m (8H,
CH2), 1.39 s (9H, BueCH3). 13C NMR: 162.1 (N]CeH), 160.9, 140.8
10 1H NMR: 8.01 d (1H, AreH), 7.79 d (2H, AreH), 7.62 d (2H,
t

A.M. Rimkus, H.G. Alt / Journal of Organometallic Chemistry 820 (2016) 30e40
39
AreH), 7.35e7.45 m (5H, AreH), 7.15e7.23 m (2H, AreH), 6.16 s (1H,
Calc: C, 42.6; H, 4.69; N, 3.10.
AreCH), 5.87e6.06 m (1H, CH]CH2), 5.03e5.20 m (2H, ]CH2),
4.84 s (1H, Flu-H9), 3.98 s (1H, Ind-H1), 2.23e2.36 m (2H, CH2),
2.08e2.22 m (1H, CH2), 1.65e1.83 m (1H, CH2), 1.27 s (br, 6H, CH3).
13C NMR: 150.9, 149.7, 145.2, 143.4, 143.2, 142.1, 141.7 (Cq), 138.6
(CH]), 133.3, 127.0, 126.7, 126.4, 126.3, 126.0, 125.8, 125.0, 124.7,
123.5, 122.4, 119.9, 119.4 (AreCH), 114.8 (CH2), 53.4 (CH; Flu-C9),
47.7 (CH; Ind-C1), 40.2 (Cq), 36.9 (CH2), 32.0 (CH2), 24.3 (br, 2C)
(CH3).
4.6.9. General synthesis of the trinuclear complexes 15 and 16
The indenylfluorenyl substituted phenoxyimine compound
(0.4 mmol) was dissolved in tetrahydrofuran (20 ml) at room
temperature. Then sodium hydride (1.2 mmol), suspended in
tetrahydrofuran (10 ml), was added. The reaction mixture was
stirred for 1 h at room temperature until the hydrogen gas pro-
duction ended. After addition of zirconium tetrachloride
(0.6 mmol) stirring was continued for 20 h at room temperature.
The solvent was then evaporated in vacuo and dichloromethane
(30 ml) was added. The mixture was filtered over sodium sulphate.
After evaporating the solvent to 5 ml, n-pentane (50 ml) was added
and the complexes precipitated from the solution. After storage for
one day at ꢁ80 ꢀC the complexes could be separated from the
overlaying solution. Washing three times with n-pentane and
drying in vacuo finally gave the pure complexes. Yield: 55%.
15 1H NMR: 8.01 s (2H, N]CeH), 6.82e7.92 m (40H, AreH),
3.75e3.89 m (2H, CH2), 1.56 s (18H, tBueCH3, tBueCH3), 1.26 s (12H,
CH3). MS m/z: 1703 Mþ (0), 918 M e Ligand e Me e ZrCl2 (18),
865 M e Ligand e 2 Me e ZrCl2 e Cl (27), 330 FlueC3H6eInd (29),
165 Flu (100).
4.6.7. Synthesis route for Sonogashira coupling reactions
A phenoxyimine compound (1 mmol), bis((triphenyl)phos-
phine)palladium dichloride (0.01 mmol) and copper(I) iodide
(0.02 mmol) were dissolved in triethylamine (20 ml). Then an
u-
alkynyl substituted C1-bridged indenylfluorenyl compound
(1 mmol) was added and the reaction mixture was stirred for 20 h
at room temperature. The solvent was then removed in vacuo, and
water (20 ml) and n-pentane (20 ml) were added. The aqueous
layer was extracted with n-pentane two more times and the
combined organic layers were dried over sodium sulphate. The raw
products were filtered over silica. Yields: 50e70%.
11 1H NMR: 13.64 s (br, 1H, OH), 8.57 s (1H, N]CeH),
7.69e7.79 m (4H, AreH), 7.51e7.54 m (1H, AreH), 7.18e7.45 m
(12H, AreH), 7.00e7.15 m (2H, AreH), 6.80e6.92 m (1H, AreH),
4.75 s (1H, Flu-H9), 3.88e3.93 m (2H, CH2), 3.67e3.78 m (1H, Ind-
16 1H NMR: 7.93e8.03 m (2H, N]CeH), 7.21e7.76 m (28H,
AreH), 6.15 s (2H, AreH), 3.68e3.72 s (2H, NeCH), 2.86e3.04 m
(2H, CH2), 2.57e2.75 m (2H, CH2), 1.72e1.87 m (16H, CH2),
t
t
H1), 1.44 s (9H, BueCH3), 1.24 s (6H, CH3). 13C NMR: 163.7 (N]
1.49e1.54 s (12H, CH3), 1.23e1.29 s (18H, CH3, BueCH3). MS m/z:
CeH),160.5, 151.7, 148.1, 147.7, 145.1, 143.1, 142.0, 141.6, 137.7, 122.0,
118.9, 118.8 (Cq), 138.3 (2C), 132.7, 130.8 (2C), 130.5, 126.7 (2C),
125.9, 124.9 (2C), 123.8, 123.1 (2C), 122.4, 121.1, 119.7 (2C), 119.4,
118.5 (AreCH), 91.2, 89.5 (Cq, C^C), 53.3 (CH, Ind-C1), 47.1 (CH, Flu-
C9), 36.9, 34.9 (Cq), 29.7 (CH2), 29.2 (CH3, tBueCH3). MS m/z: 611 Mþ
(13), 446 M e Flu (19), 290 M e FlueC3H6eInd (100), 275 M e
FlueC3H6eInd e Me (17), 165 Flu (18).
1688 Mþ (0), 924 M e Ligand e ZrCl2 (3), 908 M e Ligand e Me e
ZrCl2 (5), 874 M e Ligand e 2 Me e ZrCl2 e Cl (6), 330 Flu e C3H6-
Ind (16), 165 Flu (100).
4.6.10. Polymerization of ethylene with complexes 13e16
The corresponding zirconium complex (1e5 mg) was dissolved
in 5 ml of toluene. Then the solution was filled into a flask con-
taining 250 ml of n-pentane. A 1l Büchi autoclave was evacuated
and refilled with argon. This procedure was repeated several times
and the mixture was added. Then after short evacuation, the
autoclave was set under an ethylene pressure of 1 bar and meth-
ylaluminoxane (MAO, 30% in toluene, Zr:Al ratio ¼ 1:500) was
added to the solution. The mixture was then stirred for 1 h at 35 ꢀC
respectively 60 ꢀC applying an ethylene pressure of 10 bar. The
ethylene pressure was released and, after cooling to room tem-
perature, the polymer mixture was taken out of the reactor. The
obtained polymer was washed with hydrochloric acid, water and
acetone and was finally dried in vacuo.
12 1H NMR: 14.39 s (br, 1H, OH), 8.25 s (1H, N]CeH), 7.96 d (1H,
AreH), 7.76 d (1H, AreH), 7.70 d (2H, AreH), 7.08e7.40 m (10H,
AreH), 6.16 d (1H, AreH),4.75 s (1H, Flu-H9), 3.68e3.77 m (2H, Ind-
H1, NeCH), 2.83e2.91 m (1H, CH2), 2.58e2.66 m (1H, CH2),
1.88e1.98 m (2H, CH2), 1.78e1.87 m (2H, CH2), 1.62e1.76 m (4H,
t
CH2), 1.40 s (9H, BueCH3), 1.17e1.33 m (6H, CH3). 13C NMR: 162.4
(N]CeH), 160.8, 151.6, 148.3, 145.2, 145.1, 143.4, 142.1, 142.0, 137.8,
118.4, 112.5 (Cq), 133.0, 132.6, 132.4, 127.1, 127.0, 126.8, 126.3, 126.2,
126.0, 125.9, 125.0, 124.0, 122.4, 119.4, 119.4 (AreCH), 86.2, 81,5 (Cq,
C^C), 69.8 (NeCH), 53.3 (CH, Ind-C1), 47.3 (CH, Flu-C9), 40.2, 34.7
(2C) (CH2), 34.8 (Cq), 29.2 (CH3, tBueCH3), 24.4 (2C) (CH2), 22.2 (Cq).
MS m/z: 603 Mþ (13), 438 M e Flu (6), 282 M e FlueC3H6eInd
(100), 267 M e FlueC3H6eInd e Me (4), 165 Flu (45).
4.6.11. Hydrosilylation reactions with metallocene ligand precursors
and dichloro methyl silane
4.6.8. General synthesis of the phenoxyimine complexes 13 and 14
The phenoxyimine compound (6 mmol) was dissolved in
tetrahydrofuran at room temperature. Then sodium hydride
(6 mmol), suspended in tetrahydrofuran, was added. The reaction
mixture was stirred for 1 h at room temperature until the hydrogen
gas production ended. After addition of zirconium tetrachloride
(3 mmol) stirring was continued for 20 h at room temperature. The
solvent was then evaporated in vacuo and methylene chloride
(30 ml) was added. The mixture was filtered over sodium sulphate.
After evaporating the solvent to 5 ml, n-pentane (50 ml) was added
and the complexes precipitated from the solution. Washing three
times with n-pentane and drying in vacuo finally gave the com-
plexes. Yields: 80e90%.
The metallocene ligand precursor 10 (6.41 mmol) and dichloro
methyl silane (6.41 mmol) were dissolved in n-pentane (5e10 ml)
and solid hexachloro platinum acid (0.03 mmol) was added. The
reaction mixture was stirred for 20 h at room temperature and then
filtered over sodium sulphate. The solvent was removed in vacuo
and compound 17 was obtained and used without further
purification.
4.6.12. Synthesis of the pyrazolyl functionalized metallocene ligand
precursor 18
To compound 17 (5.83 mmol), dissolved in dichloromethane
(30 ml), triethylamine (11.66 mmol) was added. Then 3,5-dime-
thylpyrazole (11.66 mmol) was added quickly. After stirring for 12 h
at room temperature the solvent was removed. The residue was
dissolved in n-pentane, and the suspension was filtered over so-
dium sulphate. The solvent was removed in vacuo. Yield: 98%.
18 1H NMR: 7.69 d (1H, AreH), 7.48e7.55 m (3H, AreH), 7.29 d
(1H, AreH), 7.09e7.21 m (6H, AreH), 6.93e6.98 m (1H, AreH),
13 MS m/z: 918 Mþ (67), 881 M e Cl (99), 866 M e Cl e Me (29).
Elemental analyses: Found: C, 44.30; H, 3.79; N, 3.00. Calc: C, 44.50;
H, 3.73; N, 3.05.
14 MS m/z: 902/904 Mþ (5), 895 M e Cl (6), 777 M e I (11), 742 M
e I e Cl (12). Elemental analyses: Found: C, 42.2; H, 4.78; N, 3.07.

40
A.M. Rimkus, H.G. Alt / Journal of Organometallic Chemistry 820 (2016) 30e40
[10] A. Elagab, H.G. Alt, Inorg. Chim. Acta 437 (2015) 26.
5.81e5.82 m (1H, AreH), 5.64 s (1H, AreH), 5.57 s (1H, AreH),
4.60 s (1H, Flu-H9), 3.46 s (1H, Ind-H1), 2.11e2.15 m (4H, CH3),
1.68e1.71 m (4H, CH3),1.70 s (4H, CH3),1.41 s (2H, CH2),1.17e1.28 m
(4H, CH2), 0.95e1.14 s (br, 6H, CH3), 0.84 t (2H, CH2), 0.80 s (3H,
SieCH3). 13C NMR: 151.9, 150.2, 149.4, 146.3, 144.9, 144.8, 142.8,
142.6, 141.7 (2C), 141.3 (Cq), 133.0, 125.6, 126.2, 126.1, 126.0, 125.7,
125.4, 124.4, 124.1, 123.0, 121.8, 119.3, 118.9, 107.9, 103.3 (AreCH),
53.0 (Ind-C1), 47.6 (Flu-C9), 30.5 (Cq), 39.6, 36.1, 30.6,14.5 (CH2), 13.1
(2C) (CH3), 10.7 (2C) (CH3), ꢁ2.7 (SieCH3).
[11] W. Kaminsky, M. Hoff, S. Derlin, Macromol. Chem. Phys. 208 (2003) 1341.
[12] W. Kaminsky, Adv. Polym. Sci. 258 (2013) 1e300. Polyolefins: 50 years after
Ziegler and Natta II. Springer. Wiley, 1999. ISBN: 978-0-471-99911-9.
[13] W. Kaminsky, M. Fernandes, Polyolefins J. 2 (2015) 1.
[14] J.R. Severn, J.C. Chadwick, Tailoremade Polymers via Immobilization of Alpha
Olefin Polymerization Catalysts, Wiley-VCH Verlag GmbH, Weinheim, 2008
and References Therein.
[15] J. Scheirs, W. Kaminsky, Metallocene-based Polyolefins, Preparation, Proper-
ties, and Technology, Wiley, 1999. ISBN: 978-0-471-99911-9.
[16] S. S. Ivanchev, G. A. Tolstikov, V. K. Badaev, N. I. Ivancheva, I. I. Oleinik, E. V.
Sviridova, D. G. Rogozin, V. N. Kudryashov, M. S. Gabutdinov, B. N. Bobrov,
patent RU 2248374, 2005.
[17] A. M. A. Bennett, US patent 6214761, 2001 and US 20050202960 A1.
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[19] H.G. Alt, R. Ernst, J. Mol. Cat. A Chem. 195 (2003) 11.
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[21] M. Deppner, R. Burger, H.G. Alt, J. Organomet. Chem. 689 (2004) 1194.
[22] L. Pronko, WO 2004067586, 2004.
4.6.13. Synthesis of the pyrazolyl functionalized metallocene
complex 19
€
To the ligand precursor 18 (5.72 mmol), dissolved in diethyl
ether (50 ml), n-butyl lithium (11.44 mmol, 1.6 M in hexane) was
added at ꢁ78 ꢀC. After stirring for 8 h at room temperature the
reaction mixture was cooled to ꢁ78 ꢀC again. Zirconium tetra-
chloride (11.44 mmol) was added and the reaction mixture was
stirred for another 12 h at room temperature. The solvent was
removed, dichloromethane was added and the mixture was filtered
over sodium sulphate. After the dichloromethane was evaporated
to 5 ml, n-pentane was added (10 ml). The precipitated complex
was washed three times with n-pentane (15 ml) and dried in vacuo.
Yield: 69%.
[23] H. Alshammari, H.G. Alt, Polyolefins J. 1 (2014) 107.
[24] H. Alshammari, H.G. Alt, Jordan J. Chem. 9 (2014) 110.
[25] K. Ahmad, H.G. Alt, Jordan J. Chem. 10 (2015) 87.
€
[26] B. Peifer, Dissertation, Universitat Bayreuth, 1995.
[27] B. Peifer, W. Milius, H.G. Alt, J. Organomet. Chem. 553 (1998) 205.
[28] H.G. Alt, M. Jung, G. Kehr, J. Organomet. Chem. 562 (1998) 153.
[29] M. Jung, H. G. Alt, M. B. Welch, US 5886202, 1999.
[30] T. Fujita, Y. Tohi, M. Mitani, S. Matsui, J. Saito, M. Nitabaru, K. Sugi, H. Makio, T.
Tsutsui, EP 874005, 1998.
[31] S. Matsui, T. Fujita, Catal. Today 66 (2001) 63.
[32] S. Matsui, M. Mitani, J. Saito, Y. Tohi, H. Makio, N. Matsukawa, Y. Takagi,
K. Tsuru, M. Nitabaru, T. Nakano, H. Tanaka, N. Kashiwa, T. Fujita, J. Am. Chem.
Soc. 123 (2001) 6847.
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T. Nakano, T. Fujita, Chem. Lett. (1999) 1065.
19 1H NMR: 7.46e7.99 m (4H, AreH), 7.01e7.44 m (6H, AreH),
6.71e6.99 m (2H, AreH), 5.73e5.96 m (1H, AreH), 2.06e2.53 m
(8H, CH2), 1.41e1.90
m (6H, CH3), 1.08e1.40 m (6H, CH3),
[34] N. Matsukawa, EP 1013674, 2000.
0.63e0.98 m (6H, CH3), 0.22e0.63 m (3H, SieCH3). MS m/z:
[35] M. Mitani, Y. Yoshida, J. Mohri, K. Tsuru, S. Ishii, S. Kojoh, T. Matsugi, J. Saito, N.
Matsukawa, S. Matsui, T. Nakano, H. Tanaka, N. Kashiwa, T. Fujita, WO
2001055231, 2001.
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D.J. Williams, Chem. Commun. (1998) 1651.
1004 Mþ (0), 532 M e Pz(Me2)2SiMeZrCl4 (5), 479 M e Pz(Me2)2
-
SiMeZrCl4 e C4H8 (4), 424 M e FlueC(CH2)eIndeC2H4eZrCl2 (8),
260 M e FlueC(CH2)eIndeC2H4eZrCl2eZrCl2 (30), 165 Fluorene
(100), 96 Pz(Me2) (100). Elemental analyses: Found: C, 48.20; H,
4.85; N, 5.67. Calc: C, 47.90; H, 4.42; N, 5.58.
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J. Am. Chem. Soc. 127 (2005) 1082.
4.6.14. Polymerization of ethylene with complex 19
The zirconium complex (1e5 mg) was dissolved in 5 ml of
toluene. Then methylaluminoxane (MAO, 30% in toluene, Zr:Al
ratio ¼ 1:2500) was added to the solution and filled into a flask
containing 250 ml of n-pentane. A 1l autoclave was evacuated and
refilled with argon several times and the catalyst mixture was
added. The mixture was then stirred for 1 h at 60 ꢀC under an
ethylene pressure of 10 bar. The ethylene pressure was released,
and after cooling to room temperature the polymer mixture was
taken out of the reactor. The obtained polymer was washed with
hydrochloric acid, water and acetone and it was finally dried in
vacuo.
[43] A. Kestel-Jakob, H.G. Alt, Jordan J. Chem. 2 (2007) 219.
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G.A. Solan, A.J.P. White, D.J. Willians, Chem. Commun. (1998) 849.
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€
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€
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Acknowledgement
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[51] H.G. Alt, R. Ernst, I. Bohmer, J. Mol. Catal. A Chem. 191 (2003) 177.
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[52] R. Ernst, Dissertation, Universitat Bayreuth, 2000.
We thank Saudi Basic Industries Corporation (SABIC) for the
financial support.
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