polymers
Article
Influence of Ligand Backbone Structure and
Connectivity on the Properties of
Phosphine-Sulfonate Pd(II)/Ni(II) Catalysts
Zixia Wu, Changwen Hong, Hongxu Du, Wenmin Pang and Changle Chen *
Chinese Academy of Sciences Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and
Engineering, University of Science and Technology of China, Hefei 230026, China;
[email protected] (Z.W.); [email protected] (C.H.); [email protected] (H.D.);
[email protected] (W.P.)
* Correspondence: [email protected]; Tel.: +86-551-6360-1495
Academic Editor: Marinos Pitsikalis
Received: 1 April 2017; Accepted: 3 May 2017; Published: 9 May 2017
Abstract: Phosphine-sulfonate based palladium and nickel catalysts have been extensively studied in
ethylene polymerization and copolymerization reactions. Previously, the majority of the research
works focused on the modifications of the substituents on the phosphorous atom. In this contribution,
we systematically demonstrated that the change of the ligand backbone from benzene to naphthalene
could greatly improve the properties of this class of catalysts. In the palladium system, this change
could increase catalyst stability and polyethylene molecular weights. In the nickel system, this change
could dramatically increase the polyethylene molecular weights. Most interestingly, the change
in the connectivity of phosphine and sulfonate moieties to the naphthalene backbone could also
significantly influence the catalyst properties.
Keywords: phosphine-sulfonate; palladium; nickel; olefin polymerization; copolymerization
1. Introduction
In olefin polymerization, late transition metal catalysts have attracted much attention because
of their low oxophilicity, and correspondingly the potentials to incorporation polar functionalized
monomers into polyolefins. Among the numerous late transition metal catalysts, the Brookhart type
α-diimine Ni(II) and Pd(II) [1–14], phenoxyminato based Ni(II) [15–21] and the phosphine-sulfonate
Pd(II) catalysts [22–35] are the most extensively studied systems. It has been demonstrated that the
properties of these catalysts are very sensitive to the ligand sterics. Specifically, it has been well
established that the steric bulk on the axial positions in α-diimine systems could decrease the chain
transfer rate, and increase the polyolefin molecular weight (Scheme 1, I) [1,2,36–39]. Similarly, the steric
bulk on the axial positions in phenoxyminato (Scheme 1, II) and phosphine-sulfonate (Scheme 1, III)
systems is crucial to obtain high-performance catalysts [40–42].
The modulation of the steric effect on the axial positions directly affects the steric environment
of the metal center. In addition, the ligand backbone structure could indirectly influence the steric
environment of the metal center, and correspondingly affect the properties of the metal catalysts.
For example, different substituents on the backbone R position could greatly alter the properties
of the α-diimine Pd(II) and Ni(II) catalysts (Scheme 1, IV) [43–45]. Despite the various efforts to
modify the phosphine-sulfonate ligands, there have been very few studies on the modifications of the
ligand backbone structures [46]. Recently, our group showed that the catalyst stability and activity
could be greatly enhanced by changing the phosphine-sulfonate backbone from a benzene bridge to a
naphthalene one (Scheme 1, V) [47]. In this contribution, we hope to further improve the properties of
Polymers 2017, 9, 168; doi:10.3390/polym9050168
www.mdpi.com/journal/polymers
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the naphthalene based phosphine-sulfonate Pd(II) and Ni(II) catalysts by: (1) changing the linking
Polymers 2017, 9, 168
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the linking
position of the
phosphine
and the
sulfonate
on the naphthalene
backbone;
position
of the phosphine
and
the sulfonate
moieties
onmoieties
the naphthalene
backbone;
and (2)and
using a
(2)
using
a
sterically
very
bulky
bi-aryl
substituent
on
the
phosphorous
atom.
sterically
very bulky
bi-aryl
on the
phosphorous
atom.
the linking
position
of thesubstituent
phosphine and
the sulfonate
moieties
on the naphthalene backbone; and
(2) using a sterically very bulky bi-aryl substituent on the phosphorous atom.
Scheme
1. The
α-diimine,
phenoxyminato
based
olefin
polymerization
catalysts.
Scheme
1. The
α-diimine,
phenoxyminatoand
and phosphine-sulfonate
phosphine-sulfonate based
olefin
polymerization
catalysts.
Scheme 1. The α-diimine, phenoxyminato and phosphine-sulfonate based olefin polymerization catalysts.
2. Results
Discussion
2. Results
andand
Discussion
2. Results
and Discussion
Literature
procedure was employed to prepare the ligands [47]. First, the 2-naphthalenesulfonic
Literature
procedure
was employed to prepare the ligands [47]. First, the 2-naphthalenesulfonic
acid was converted to the toluidinium salt from the reaction with excess amount of p-toluidine
procedure
was employedsalt
to prepare
the ligands
[47].
First,
the 2-naphthalenesulfonic
acid wasLiterature
converted
to the toluidinium
from the
reaction
with
excess
amount of p-toluidine
(Scheme 2, see Supplementary Materials, Experimental Sections). The corresponding lithium salt was
acid
was
converted
to
the
toluidinium
salt
from
the
reaction
with
excess
amount
of lithium
p-toluidine
(Scheme
2, see Supplementary Materials, Experimental Sections). The corresponding
salt was
generated from the reaction with 1 equivalent of nBuLi, and dehydrated using a dean-stark
n
(Scheme
2,
see
Supplementary
Materials,
Experimental
Sections).
The
corresponding
lithium
saltapparatus
was
generated
from
the
reaction
with
1
equivalent
of
BuLi,
and
dehydrated
using
a
dean-stark
apparatus in refluxing toluene. Subsequently, ligands L1-L3 were obtained in 39–47% yields from
generated from the reaction with 1 equivalent of nBuLi, and dehydrated using a dean-stark
in refluxing
toluene.
Subsequently,
ligands
L1-L3
were
in 39–47% yields
from the
the reaction
of 1 equivalent
of nBuLi
with the
lithium
saltobtained
in THF (tetrahydrofuran)
followed
by reaction
the
apparatus in refluxing
toluene. Subsequently, ligands L1-L3 were obtained in 39–47% yields from
n
of 1 equivalent
of2PCl.
BuLi
with
then lithium
salt in THFby
(tetrahydrofuran)
by the
addition of
addition of R
These
ligands
were characterized
by 1H, 13C, and 31P followed
NMR (Nuclear
Magnetic
the reaction of 1 equivalent of BuLi with the lithium
salt in THF
(tetrahydrofuran) followed by the
1 H, 13 C,(see
31 P NMR (Nuclear
Resonance)
spectroscopycharacterized
(Bruker, Karlsruhe,
Germany)
Supplementary
Materials,
Figures S1–S9),
R2 PCl.
Theseofligands
by by
and
Magnetic
Resonance)
1H, 13
addition
R2PCl. were
These ligands were characterized
by by
C, and 31P NMR (Nuclear
Magnetic
elemental
analysis
and
Mass
spectrometry
(EI+,
Bruker
Daltonics
Inc.,
Billerica,
MA,
USA).
spectroscopy
(Bruker,
Karlsruhe,
Germany)
Supplementary
Materials,
FiguresFigures
S1–S9),
elemental
Resonance)
spectroscopy
(Bruker,
Karlsruhe,(see
Germany)
(see Supplementary
Materials,
S1–S9),
analysis
and Mass
spectrometry
(EI+, Bruker
Inc., Billerica,
MA,MA,
USA).
elemental
analysis
and Mass spectrometry
(EI+,Daltonics
Bruker Daltonics
Inc., Billerica,
USA).
Scheme 2. Synthesis of the phosphine-sulfonate ligands and the palladium and nickel complexes.
Scheme 2. Synthesis of the phosphine-sulfonate ligands and the palladium and nickel complexes.
Scheme
2. Synthesis
of the phosphine-sulfonate
ligands 2and
the palladium
and nickel complexes.
The reactions
of ligands
L1-L3 with (TMEDA)PdMe
(TMEDA
= tetramethylethylenediamine)
in DMSO (dimethylsulfoxide) led to the formation of the Pd(II) complexes (Pd1-Pd3) at 41–48%
The reactions of ligands L1-L3 with (TMEDA)PdMe2 (TMEDA = tetramethylethylenediamine)
yields
(Schemeof
2).ligands
The reaction
of ligands
L1-L3 with Na2(TMEDA
CO3 and trans-[(PPh
3)2Ni(Cl)Ph] afforded
The
reactions
L1-L3
(TMEDA)PdMe
= tetramethylethylenediamine)
in
in
DMSO
(dimethylsulfoxide)
ledwith
to the
formation of the
(Pd1-Pd3) at 41–48%
2 Pd(II) complexes
the desired Ni(II) complexes (Ni1-Ni3) at 34–76% yields. These metal complexes were characterized
yields
(Scheme 2). The reaction
ligands
L1-L3 of
with
2CO3 complexes
and trans-[(PPh
3)2Ni(Cl)Ph]
affordedyields
DMSO
(dimethylsulfoxide)
led toofthe
formation
theNa
Pd(II)
(Pd1-Pd3)
at 41–48%
using 1H, 13C, and 31P NMR (see Supplementary Materials, Figures S10–S20), elemental analysis and
the desired
Ni(II)
complexes
(Ni1-Ni3)
at 34–76%
yields.
complexes
were characterized
(Scheme
2). The
reaction
of ligands
L1-L3
with Na
COThese
andmetal
trans-[(PPh
)2 Ni(Cl)Ph]
afforded the
2
3
3
MALDI-TOF-MS
(Matrix Assisted Laser Desorption Ionization-Time of Flight-Mass Spectrometry).
1H, 13C, and 31P NMR (see Supplementary Materials, Figures S10–S20), elemental analysis and
using
desired
Ni(II)
complexes
(Ni1-Ni3)
at
34–76%
yields.
These
metal
complexes
were
characterized
For comparison purpose, the palladium complex Pd2′/Pd2″ and the nickel complex Ni2′/Ni1″ were
Assisted
Laser Desorption
Ionization-Time
of Flight-Mass
Spectrometry).
1 H, 13 C, and 31(Matrix
usingMALDI-TOF-MS
P NMR
(see Supplementary
Materials,
Figures S10–S20),
elemental
analysis and
prepared
according
to literature
procedures [48,49].
For comparison purpose, the palladium complex Pd2′/Pd2″ and the nickel complex Ni2′/Ni1″ were
MALDI-TOF-MS (Matrix Assisted Laser Desorption Ionization-Time of Flight-Mass Spectrometry).
prepared according to literature procedures [48,49]. 0
0
For comparison purpose, the palladium complex Pd2 /Pd2” and the nickel complex Ni2 /Ni1” were
prepared according to literature procedures [48,49].
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Themolecular
molecularstructures
structuresofofPd2
Pd2and
andNi1
Ni1were
weredetermined
determinedby
byX-ray
X-raydiffraction
diffractionanalysis
analysis(Figure
(Figure1;1;
The
see
CIF
files
and
Supplementary
Materials,
Tables
S1
and
S2).
The
geometry
at
both
the
palladium
see CIF files and Supplementary Materials, Tables S1 and S2). The geometry at both the palladium and
and
the nickel
is square
with
the methyl
or phenyl
substituent
to the phosphine
the
nickel
centercenter
is square
planarplanar
with the
methyl
or phenyl
substituent
cis to thecisphosphine
group.
group.
Clearly,
the
hydrogen
atom
on
the
C15
in
Pd2
and
C7
in
Ni1
could
exert
some
steric
influence
Clearly, the hydrogen atom on the C15 in Pd2 and C7 in Ni1 could exert some steric influence to the
to the substituents
the phosphorous
Especially,
steric
effect
could
enhancedwhen
whenthe
the
substituents
on the on
phosphorous
atom.atom.
Especially,
this this
steric
effect
could
be be
enhanced
substituentsare
arebulky.
bulky. Most
Most importantly,
importantly, this interaction
substituents
interaction could
couldpotentially
potentiallyinfluence
influencethe
theproperties
propertiesof
these
catalysts
in
ethylene
polymerization
and
copolymerization
reactions.
of these catalysts in ethylene polymerization and copolymerization reactions.
(a)
(b)
Figure 1. Molecular structures of: (a) Pd2; and (b) Ni1. Hydrogen atoms have been omitted for
Figure 1. Molecular structures of: (a) Pd2; and (b) Ni1. Hydrogen atoms have been omitted for
clarity. Selected bond lengths (Å) and angles (°) for Pd2:
Pd1-C23 = 2.067(11), Pd1-P1 = 2.211(2), Pd1-O3 =
clarity. Selected bond lengths (Å) and angles (◦ ) for Pd2: Pd1-C23 = 2.067(11), Pd1-P1 = 2.211(2),
2.143(7),
= 2.131(7),
S1-O3
= 1.469(8),
S1-O1= =1.469(8),
1.436(8), S1-O1
S1-C22== 1.436(8),
1.781(9), P1-C13
Pd1-O3Pd1-O4
= 2.143(7),
Pd1-O4
= 2.131(7),
S1-O3
S1-C22 ==1.864(3),
1.781(9),
C13-C22
=
1.387(4),
P1-Pd1-O32
=
91.3(1),
P1-Pd1-O4
=
177.3(2),
P1-Pd1-C23
=
94.7(3),
Pd1-P1-C13
=
P1-C13 = 1.864(3), C13-C22 = 1.387(4), P1-Pd1-O32 = 91.3(1), P1-Pd1-O4 = 177.3(2), P1-Pd1-C23
= 94.7(3),
115.5(3),
S1-O3-Pd1
=
112.9(4);
for
Ni1:
Ni1-C41
=
1.8873(15),
Ni1-P1
=
2.2221(4),
Ni1-P2
=
2.2100(4),
Pd1-P1-C13 = 115.5(3), S1-O3-Pd1 = 112.9(4); for Ni1: Ni1-C41 = 1.8873(15), Ni1-P1 = 2.2221(4),
Ni1-O1
1.9553(11),Ni1-O1
S1-O1 ==1.9553(11),
1.4352(13),S1-O1
P2-C23
= 1.8309(15),
P2-C17
= 1.8118(17),
P1-Ni1-O1
=
Ni1-P2 == 2.2100(4),
= 1.4352(13),
P2-C23
= 1.8309(15),
P2-C17
= 1.8118(17),
93.63(3),
P1-Ni1-C41
= 88.18(5),
P2-Ni1-O1
= 89.47(3),P2-Ni1-O1
P2-Ni1-C41== 89.62(5),
P1-Ni1-O1
= 93.63(3),
P1-Ni1-C41
= 88.18(5),
89.47(3),O1-Ni1-C41
P2-Ni1-C41= 174.92(6).
= 89.62(5),
O1-Ni1-C41 = 174.92(6).
The palladium catalysts are highly active in ethylene polymerization, with activities well above
105 g·mol−1·h−1 (Table 1, entries 1–6). Catalyst Pd3 with the biaryl substituent showed almost 10-fold
The palladium catalysts are highly active in ethylene polymerization, with activities well above
increase
in polymer molecular weight comparing with catalyst Pd1. The nickel catalysts are also
105 g·mol−1 ·h−1 (Table 1, entries 1–6). Catalyst Pd3 with the biaryl substituent showed almost 10-fold
highly active in ethylene polymerization, with activities comparable with those of the palladium
increase in polymer molecular weight comparing with catalyst Pd1. The nickel catalysts are also
catalysts (Table 1, entries 7–9). The palladium catalysts completely lost activity at 25 °C. However,
highly active in ethylene polymerization, with activities comparable with those of the palladium
the nickel catalysts could maintain high activity at 25 °C. Most importantly, the polyethylene
catalysts (Table 1, entries 7–9). The palladium catalysts completely lost activity at 25 ◦ C. However,
molecular weight could be dramatically increased at
lower polymerization temperature. For the
the nickel catalysts could maintain high activity at 25 ◦ C. Most importantly, the polyethylene molecular
case of Ni3, molecular weight of up to 142,300 could be achieved (Table 1, entry 12). Similar with
weight could be dramatically increased at lower polymerization temperature. For the case of Ni3,
the palladium case, catalyst Ni3 with the biaryl substituent showed much higher polymer
molecular weight of up to 142,300 could be achieved (Table 1, entry 12). Similar with the palladium
molecular weight than catalysts Ni1 and Ni2.
case, catalyst Ni3 with the biaryl substituent showed much higher polymer molecular weight than
Some very interesting results were obtained from the comparisons between catalysts Pd2/Ni2
catalysts Ni1 and Ni2.
and our previously reported catalysts Pd2′/Ni2′. Catalyst Pd2 showed similar activity and similar
Some very interesting results were obtained from the comparisons between catalysts Pd2/Ni2
polymer molecular weight with catalyst 0Pd2′ 0(Table 1, entry 2 versus 13). The polyethylene
and our previously reported catalysts Pd2 /Ni2 . Catalyst Pd2 showed similar activity and similar
molecular weights for catalysts Pd2 and Pd2′0 are much higher than that of the conventional catalyst
polymer molecular weight with catalyst Pd2 (Table 1, entry 2 versus 13). The polyethylene molecular
Pd2″ with the benzene as ligand0 backbone. In terms of catalyst stability, catalyst Pd2 showed
weights for catalysts Pd2 and Pd2 are much higher than that of the conventional catalyst Pd2” with the
slightly better stability than catalyst Pd2′, both of which are much more stable than conventional
benzene as ligand backbone. In terms of catalyst stability, catalyst Pd2 showed slightly better stability
catalyst Pd2″ (Figure
2). Clearly, the change in the ligand backbone from benzene to naphthalene
than catalyst Pd20 , both of which are much more stable than conventional catalyst Pd2” (Figure 2).
could significantly improve the performance of phosphine-sulfonate palladium catalysts. However,
Clearly, the change in the ligand backbone from benzene to naphthalene could significantly improve
the change in the connectivity of the phosphine moiety and the sulfonate moiety to the naphthalene
the performance of phosphine-sulfonate palladium catalysts. However, the change in the connectivity
backbone does not influence the properties of these palladium catalysts.
of the phosphine moiety and the sulfonate moiety to the naphthalene backbone does not influence the
properties of these palladium catalysts.
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Table 1. Ethylene polymerization catalyzed by Pd(II) and Ni(II) complexes a.
b
c
d
Entry Catalyst
(μmol)polymerization
T (°C) Yieldcatalyzed
(g) Activity
wc
Polydispersity
Table 1. [cat]
Ethylene
by Pd(II) M
and
Ni(II)
complexes a . Tm (°C)
Pd1
1
10
80
2
2.0
2100
1.15
109
Pd2
2
10
80
2.4
2.4
5100 c
2.36
117 ◦ d
Entry
Catalyst [cat] (µmol)
T (◦ C)
Yield (g)
Mw
Polydispersity c
Activity b
Tm ( C)
Pd3
3
10
80
5
5.0
27,800
2.56
129
1 4
Pd1Pd1
10 2
8080
2
2.0
2100
1.15
0.5
2.5
3200
2.06
114 109
2 5
Pd2Pd2
10 2
8080
2.4
2.4
5100
2.36
0.4
2.0
5700
2.18
124 117
3
Pd3
10
80
5
5.0
27,800
2.56
129
Pd3
6
2
80
1.2
6.0
24,800
1.84
131
4
Pd1
2
80
0.5
2.5
3200
2.06
114
Ni1
7
10
80
1.9
1.9
3600
1.58
128
5
Pd2
2
80
0.4
2.0
5700
2.18
124
Ni2
2.2
2.2
9100
2.18
129
6 8
Pd3
2 10
8080
1.2
6.0
24,800
1.84
131
5.7
5.71.9
17,500
2.041.58
133 128
7 9
Ni1Ni3
10 10
8080
1.9
3600
0.7
1.72.2
37,200
3.642.18
134 129
8 10
Ni2Ni1
10 2
8025
2.2
9100
0.5
1.35.7
58,600
1.992.04
135 133
9 11
Ni3Ni2
10 2
8025
5.7
17,500
1.4
3.51.7
142,300
1.513.64
136 134
10 12
Ni1Ni3
2 2
2525
0.7
37,200
11 13
Ni2Pd2′
2 10
2580
0.5
58,600
2.1
2.11.3
4200
2.281.99
123 135
12 14
Ni3Pd2″
2 10
2580
1.4
142,300
1.4
1.43.5
1800
1.441.51
115 136
0
13 15 Pd2Ni2′
10 10
8080
2.1
4200
1.5
1.52.1
4100
1.462.28
124 123
14 16 Pd2”Ni2′
10 2
8025
1.4
1.4
1800
1.44
0.4
2.0
27,800
2.57
133 115
0
15 17 Ni2Ni1″
10 10
8080
1.5
1.5
4100
1.46
trace
- 124
16
Ni20
2
25
0.4
2.0
27,800
2.57
133
Ni1″
18
2
25
trace
17
Ni1”
10
80
trace
a Polymerization conditions: toluene = 22 mL, CH2Cl2 = 3 mL, ethylene = 9 atm, 80 °C, time = 1 h.
18
Ni1”
2
25
trace
-
◦ C, time = 1 h. b Activity
Activity
is in unit
of 10 toluene
g·mol =·h
. Determined
byethylene
Gel Permeation
(GPC)isin
Polymerization
conditions:
22 mL,
CH2 Cl2 = 3 mL,
= 9 atm, 80Chromatograph
in
5 g·mol−1 ·h−1 . c Determined by Gel Permeation Chromatograph (GPC) in trichlorobenzene
d
unit
of
10
at 150 ◦ C
trichlorobenzene at 150 °C (see Supplementary Materials, Figures S36–S49). Melting temperature
d
(see Supplementary
Figures S36–S49).
temperature
was(see
determined
by differential
scanning
was
determined Materials,
by differential
scanning Melting
calorimetry
(DSC)
Supplementary
Materials,
calorimetry (DSC) (see Supplementary Materials, Figures S26–S35).
ba
5
−1
−1
c
Figures S26–S35).
◦ Cfor
Figure
Figure 2.
2. Polyethylene
Polyethyleneyield
yieldversus
versus polymerization
polymerization time
time at
at 80
80 °C
forcatalysts
catalystsPd2,
Pd2,Pd2′
Pd20and
andPd2″.
Pd2”.
In the nickel system, catalyst Ni2 showed polyethylene molecular weight twice as much as that
In the nickel system, catalyst Ni2 showed polyethylene molecular weight twice as much as that
of catalyst Ni2′0 (Table 1, entry 8 versus 14, entry 11 versus 15). This suggested that the very small
of catalyst Ni2 (Table 1, entry 8 versus 14, entry 11 versus 15). This suggested that the very small
perturbations in ligand sterics could exert significant effect on the properties of the
perturbations in ligand sterics could exert significant effect on the properties of the phosphine-sulfonate
phosphine-sulfonate nickel catalysts. Most interestingly, more dramatically differences were
nickel catalysts. Most interestingly, more dramatically differences were observed for the cases of
observed for the cases of catalyst Ni1 versus catalyst Ni1″ bearing phenyl substituent on the
catalyst Ni1 versus catalyst Ni1” bearing phenyl substituent on the phosphorous atom. No isolate
phosphorous atom. No isolate solid polymer product was generated by catalyst Ni1″ in ethylene
solid polymer product was generated by catalyst Ni1” in ethylene polymerization at either 80 or
polymerization
at either 80 or 25 °C. This agrees well with literature results [9]. In contrast, catalyst
25 ◦ C. This agrees well with literature results [9]. In contrast, catalyst Ni1 demonstrated high activity
Ni1 demonstrated
high activity (up to 1.9 × 105 g·mol−1·h−1), high polymer molecular weight (up to
(up to 1.9 × 105 g·mol−1 ·h−1 ), high polymer molecular weight (up to 37,200) and high melting
37,200) and high ◦melting temperature (134 °C) in ethylene polymerization. Cleary, the ligand
temperature (134 C) in ethylene polymerization. Cleary, the ligand backbone structure also plays an
backbone structure also plays an important role in determining the catalyst properties.
important role in determining the catalyst properties.
The palladium catalysts Pd1-Pd3 can also initiate efficient ethylene/metal acrylate
copolymerization, with comonomer incorporation ratios ranging between 3% and 27% (Table 2,
Polymers 2017, 9, 168
5 of 9
Polymers 2017, 9, 168
5 of 8
Polymers 2017, 9, 168
5 of 8
Polymers 2017, 9, 168
5 of 8
Polymers
168 polymer molecular weights were dramatically reduced comparing with those
5 ofin
8
entries 2017,
1–6).9, The
Polymers 2017,
168 polymer molecular weights were dramatically reduced comparing with those
5 ofin8
entries
1–6).9,The
ethylene
homopolymerization.
Because
of the
great
performance
of catalyst
Ni3with
in ethylene
entries
1–6).
weights
were
dramatically
reduced
comparing
those
Polymers
2017,
9,The
168 polymer molecular
5 ofin
8
ethylene
homopolymerization.
Because
of the
great
performance
of catalyst
Ni3with
in ethylene
entries
1–6).
weights
were
dramatically
reduced
comparing
those
Polymers
2017,
9,The
168 polymer
5also
ofin8
homopolymerization,
its molecular
properties
in ofethylene/polar
monomer
copolymerization
ethylene
homopolymerization.
Because
the
great
performance
of catalyst
Ni3with
inwere
ethylene
entries
1–6).
The
polymer
molecular
weights
were
dramatically
reduced
comparing
those
in
Polymers
2017,
9,
168
5
of
homopolymerization,
its properties
in ofethylene/polar
monomer copolymerization
also8
ethylene
homopolymerization.
Because
the
great
performance
of catalyst
inwere
ethylene
investigated.
Recently,
et al.
that
α-diimine
nickel
catalystNi3
could
mediate
entries
1–6).
polymer
molecular
weights
were
dramatically
reduced
comparing
with
those
Polymers
2017,
9,The
168
5also
ofin
8
homopolymerization,
itsCoates
properties
in showed
ethylene/polar
monomer
copolymerization
were
ethylene
homopolymerization.
Because
of
the
great
performance
of
catalyst
Ni3
in
ethylene
investigated.
Recently,
Coates
et
al.
showed
that
α-diimine
nickel
catalyst
could
mediate
entries
1–6).
polymer
molecular
weights
were
dramatically
reduced
comparing
with
those
Polymers
2017,
9,The
168 10-undecenoate
5also
ofin
8
homopolymerization,
itsCoates
properties
in showed
ethylene/polar
monomer
copolymerization
ethylene/methyl
copolymerization
in
the α-diimine
presence
ofnickel
MAO
(methylaluminoxane)
[50].
ethylene
homopolymerization.
Because
of
the
great
performance
of catalyst
inwere
ethylene
investigated.
Recently,
et al.
that
catalystNi3
could
mediate
entries
1–6).
The
polymer
molecular
weights
were
dramatically
reduced
comparing
with
those
in
homopolymerization,
its
properties
in
ethylene/polar
monomer
copolymerization
were
also
Polymers
2017,
9,
168
5
of
8
ethylene/methyl 10-undecenoate copolymerization in the presence of MAO (methylaluminoxane) [50].
The palladium catalysts Pd1-Pd3 can also initiate efficient ethylene/metal acrylate copolymerization,
with comonomer incorporation ratios ranging between 3% and 27% (Table 2, entries 1–6). The polymer
molecular weights were dramatically reduced comparing with those in ethylene homopolymerization.
Because of the great performance of catalyst Ni3 in ethylene homopolymerization, its properties in
ethylene
homopolymerization.
Because
ofethylene/polar
the
great
performance
of catalyst
inwere
ethylene
investigated.
Recently,
et
al.
that
α-diimine
nickel
catalyst
could
mediate
entries
1–6).
The
polymer
molecular
weights
were
dramatically
reduced
comparing
with
those
in
Our groups
showed
that
some
sterically
very
bulky
nickelNi3
catalysts
could
homopolymerization,
itsCoates
properties
in showed
monomer
copolymerization
also
ethylene/methyl
10-undecenoate
copolymerization
in
the phosphine-sulfonate
presence
of
MAO
(methylaluminoxane)
[50].
ethylene/polar
monomer
copolymerization
were
also
investigated.
Coates
et al. showed
ethylene
homopolymerization.
Because
ofvery
the
great
performance
of catalyst
Ni3
in ethylene
investigated.
Recently,
Coates
et al.
showed
that
α-diimine
nickel
catalyst
could
mediate
Our
groups
showed
that
some
sterically
bulky
phosphine-sulfonate
nickelRecently,
catalysts
could
entries
1–6).
The
polymer
molecular
weights
were
dramatically
reduced
comparing
with
those
in
homopolymerization,
its
properties
in
ethylene/polar
monomer
copolymerization
were
also
ethylene/methyl
10-undecenoate
copolymerization
in
the
presence
of
MAO
(methylaluminoxane)
[50].
ethylene
homopolymerization.
Because
of
the
great
performance
of
catalyst
Ni3
in
ethylene
copolymerize
ethylene
with
various
polar
monomers
[51].
Here,reduced
Ni3
could
also
achieve
moderate
investigated.
Recently,
Coates
et al.
showed
that
α-diimine
nickel
catalyst
could
mediate
Our
groups
showed
that
some
sterically
very
bulky
phosphine-sulfonate
nickel
catalysts
could
entries
1–6).
The
polymer
molecular
weights
were
dramatically
comparing
with
those
in
homopolymerization,
its
properties
in
ethylene/polar
monomer
copolymerization
were
also
ethylene/methyl
10-undecenoate
copolymerization
in
the
presence
of
MAO
(methylaluminoxane)
[50].
that α-diimine
nickel
catalyst
could
mediate
ethylene/methyl
10-undecenoate
copolymerization
copolymerize
ethylene
with
various
polar
[51].
Here, Ni3
could
also
achieve
ethylene
homopolymerization.
Because
ofmonomers
the bulky
great
performance
of
catalyst
Ni3
in moderate
ethylene
investigated.
Recently,
Coates
et al.
showed
that
α-diimine
nickel
catalyst
could
mediate
Our
groups
showed
that
some
sterically
very
phosphine-sulfonate
nickel
catalysts
could
homopolymerization,
its
properties
incomonomer
monomer
copolymerization
also
catalytic
activity,
along
with
moderate
incorporation
and
high
copolymer
molecular
ethylene/methyl
10-undecenoate
copolymerization
in
the
presence
MAO
(methylaluminoxane)
[50].
copolymerize
ethylene
with
various
polar
monomers
[51].
Here, of
Ni3
could
also
achieve
moderate
ethylene
homopolymerization.
Because
ofethylene/polar
the bulky
great
performance
of
catalyst
Ni3
inwere
ethylene
investigated.
Recently,
Coates
et al.
showed
that
α-diimine
nickel
catalyst
could
mediate
Our
groups
showed
that
some
sterically
very
phosphine-sulfonate
nickel
catalysts
could
catalytic
activity,
along
with
moderate
incorporation
and
high
copolymer
molecular
homopolymerization,
its
properties
incomonomer
ethylene/polar
monomer
copolymerization
were
also
ethylene/methyl
10-undecenoate
copolymerization
in
the
presence
of
MAO
(methylaluminoxane)
[50].
copolymerize
ethylene
with
various
polar
monomers
[51].
Here,
Ni3
could
also
achieve
moderate
in the homopolymerization,
presence
of
MAO
(methylaluminoxane)
[50].
Our
groups
showed
that
investigated.
Recently,
Coates
et
al.
showed
that
α-diimine
nickel
catalyst
could
mediate
weights
in
ethylene
copolymerization
with
methyl
10-undecenoate
6-chloro-1-hexene
(Table
2, some sterically
Our
groups
showed
that
some
sterically
very
bulky
phosphine-sulfonate
nickel
catalysts
could
catalytic
activity,
along
with
moderate
incorporation
and
high
copolymer
molecular
its
properties
incomonomer
ethylene/polar
monomer
copolymerization
were
also
ethylene/methyl
10-undecenoate
copolymerization
in
the
presence
MAO
(methylaluminoxane)
[50].
copolymerize
ethylene
with
various
polar
monomers
[51].
Here, of
Ni3
could
also
achieve
moderate
weights
in
ethylene
copolymerization
with
methyl
10-undecenoate
and
6-chloro-1-hexene
(Table
2,
investigated.
Recently,
Coates
et al.
showed
that
α-diimine
nickel
catalyst
could
mediate
Our
groups
showed
that
some
sterically
very
bulky
phosphine-sulfonate
nickel
catalysts
could
catalytic
activity,
along
with
moderate
comonomer
incorporation
and
high
copolymer
molecular
ethylene/methyl
10-undecenoate
copolymerization
in
the
presence
of
MAO
(methylaluminoxane)
[50].
entries
7
and
8).
The
palladium
complex
Pd2″
with
benzene
backbone
showed
much
lower
activity
copolymerize
ethylene
with
various
polar
monomers
[51].
Here,
Ni3
could
also
achieve
moderate
weights
in
ethylene
copolymerization
with
methyl
10-undecenoate
and
6-chloro-1-hexene
(Table
2,
very bulky
phosphine-sulfonate
nickel
catalysts
could
copolymerize
ethylene
with various polar
investigated.
Recently,
Coates
et
al. comonomer
showed
that
α-diimine
nickel
catalyst
could
mediate
Our
groups
showed
that
some
sterically
very
bulky
phosphine-sulfonate
nickel
catalysts
could
catalytic
activity,
along
with
moderate
incorporation
and
high
copolymer
molecular
entries
7in
and
8).
The
palladium
complex
Pd2″
with
benzene
backbone
showed
much
lower
activity
ethylene/methyl
10-undecenoate
copolymerization
in10-undecenoate
the
presence
of
MAO
(methylaluminoxane)
[50].
copolymerize
ethylene
with
various
polar
monomers
[51].
Here,
Ni3
could
also
achieve
moderate
weights
ethylene
copolymerization
with
methyl
and
6-chloro-1-hexene
(Table
2,
Our
groups
showed
that
some
sterically
very
bulky
phosphine-sulfonate
nickel
catalysts
could
and copolymer
molecular
weight
than
the
corresponding
complex
Pd2
with
the
naphthalene
catalytic
activity,
along
with
moderate
comonomer
incorporation
and
high
copolymer
molecular
entries
7 in
and
8).
The
palladium
complex
Pd2″
with
benzene
backbone
showed
much
lower
activity
ethylene/methyl
10-undecenoate
copolymerization
in10-undecenoate
the
presence
of
MAO
(methylaluminoxane)
[50].
copolymerize
ethylene
with
various
polar
monomers
[51].
Here,
Ni3
could
also
achieve
moderate
weights
ethylene
copolymerization
with
methyl
and
6-chloro-1-hexene
(Table
2,
and
copolymer
molecular
weight
than
the
corresponding
complex
Pd2
with
the
naphthalene
monomers
[51].
Here,
Ni3
could
also
achieve
moderate
catalytic
activity,
along
with moderate
Our
groups
showed
that
some
sterically
very
bulky
phosphine-sulfonate
nickel
catalysts
could
catalytic
activity,
along
with
moderate
comonomer
incorporation
and
high
copolymer
molecular
entries
7 in
and
8).
The
palladium
complex
Pd2″
with
benzene
backbone
showed
much
lower
activity
copolymerize
ethylene
with
various
polar
monomers
[51].
Here,
Ni3
could
also
achieve
moderate
backbone
(Table
2, entries
9 weight
and
10).
Moreover,
the
nickel
complex
Ni1″
with
benzene
backbone
is
weights
ethylene
copolymerization
with
methyl
10-undecenoate
and
6-chloro-1-hexene
(Table
2,
and
copolymer
molecular
than
the
corresponding
complex
Pd2
with
the
naphthalene
Our
groups
showed
that
sterically
very
bulky
phosphine-sulfonate
nickel
catalysts
could
catalytic
activity,
with
moderate
comonomer
incorporation
and
high
copolymer
molecular
entries
7in
and
8).
The
palladium
complex
Pd2″
with
benzene
backbone
showed
much
lower
activity
backbone
(Table
2,along
entries
9some
and
10).
Moreover,
the
nickel
complex
Ni1″
with
benzene
backbone
is copolymerization
copolymerize
ethylene
with
various
polar
monomers
[51].
Here,
Ni3
could
also
achieve
moderate
weights
ethylene
copolymerization
with
methyl
10-undecenoate
and
6-chloro-1-hexene
(Table
2,
and
copolymer
molecular
weight
than
the
corresponding
complex
Pd2
with
the
naphthalene
comonomer
incorporation
and
high
copolymer
molecular
weights
in
ethylene
catalytic
activity,
with
moderate
comonomer
incorporation
and
high
copolymer
molecular
not active
in the
copolymerization
(Table
2, monomers
entry
11).
entries
7in
and
8).
The
palladium
complex
Pd2″
with
benzene
backbone
showed
much
lower
activity
backbone
(Table
2,along
entries
9 weight
and
10).
Moreover,
the
nickel
Ni1″
with
benzene
backbone
is
copolymerize
ethylene
with
various
polar
[51].complex
Here,
Ni3
could
also
achieve
moderate
weights
copolymerization
with
methyl
10-undecenoate
and
6-chloro-1-hexene
(Table
2,
and
copolymer
molecular
than
corresponding
complex
Pd2
with
thelower
naphthalene
not
active
inethylene
the
(Table
2,the
entry
11).
catalytic
activity,
with
moderate
comonomer
incorporation
and
high
copolymer
molecular
entries
7 in
and
8). copolymerization
The
palladium
complex
Pd2″
with
benzene
backbone
showed
much
activity
backbone
(Table
2,along
entries
9 weight
and
10).
Moreover,
the
nickel
complex
Ni1″
withwith
benzene
backbone
is
weights
copolymerization
with
methyl
10-undecenoate
and
6-chloro-1-hexene
(Table
2,
and
copolymer
molecular
than
corresponding
complex
Pd2
the
naphthalene
not
active
inethylene
the
copolymerization
(Table
2,the
entry
11).
with methyl
10-undecenoate
and
6-chloro-1-hexene
(Table
2,
entries
7
and
8).
The
palladium complex
catalytic
activity,
along
with
moderate
comonomer
incorporation
and
high
copolymer
molecular
a. lower
entries
7
and
8).
The
palladium
complex
Pd2″
with
benzene
backbone
showed
much
activity
backbone
(Table
2,
entries
9
and
10).
Moreover,
the
nickel
complex
Ni1″
with
benzene
backbone
is
Table
2.
Ethylene
copolymerization
catalyzed
by
Pd(II)
and
Ni(II)
complexes
weights
in
ethylene
copolymerization
with
methyl
10-undecenoate
and
6-chloro-1-hexene
(Table
2,
and
copolymer
molecular
than
corresponding
complex
Pd2
with
the
naphthalene
a. lower
not
active
in
the
copolymerization
(Table
2,the
entry
11).
entries
7in
and
8).
The
complex
Pd2″
with
benzene
backbone
showed
much
activity
Table
2.palladium
Ethylene
copolymerization
catalyzed
by Pd(II)
andand
Ni(II)
complexes
backbone
(Table
2, entries
9 weight
and
10).
Moreover,
the
nickel
complex
Ni1″
with
benzene
backbone
is
weights
ethylene
copolymerization
with
methyl
10-undecenoate
6-chloro-1-hexene
(Table
2,
and
copolymer
molecular
weight
than
the
corresponding
complex
Pd2
with
the
naphthalene
not
active
in
the
copolymerization
(Table
2,
entry
11).
a.
Pd2” with
benzene
backbone
showed
much
lower
activity
and
copolymer
molecular
Table
2.
Ethylene
copolymerization
catalyzed
by
Pd(II)
and
Ni(II)
complexes
entries
7
and
8).
The
palladium
complex
Pd2″
with
benzene
backbone
showed
much
lower
activity
backbone
(Table
2, entries 9 weight
and 10).
Moreover,
the
nickel
complex
Ni1″Pd2
with
benzene
backbone is weight than the
Yield
and
copolymer
molecular
than
corresponding
complex
naphthalene
not
active
in the
(Table
2,the
entry
11).
a. lower
Entry
Pcopolymerization
(bar)
T ( C)
Comonomer
[M]
mol/L
Activity
X with
(%)with
M the
Polydispersity
entries
7Catalyst
and
8).
The
complex
Pd2″
with
benzene
backbone
showed
much
activity
Table
2.palladium
Ethylene
copolymerization
catalyzed
by
Pd(II)
and Ni1″
Ni(II)
complexes
backbone
(Table
2, entries
9 weight
and
10).
Moreover,
the
nickel
complex
benzene
backbone
is
Yield
(mg)
and
copolymer
molecular
than
the
corresponding
complex
Pd2
with
the
naphthalene
a. Polydispersity
Entry
Catalyst
P
(bar)
T
(
C)
Comonomer
[M]
mol/L
Activity
X
(%)
M
not
active
in
the
copolymerization
(Table
2,
entry
11).
Table
2.
Ethylene
copolymerization
catalyzed
by
Pd(II)
and
Ni(II)
complexes
corresponding
complex
Pd2
with
the
naphthalene
backbone
(Table
2,
entries
9 andis10). Moreover, the
Yield
backbone
(Table
2, entries 9weight
and 10).
Moreover,
the
nickel
complex
Ni1″
with
benzene
backbone
(mg)
and
copolymer
molecular
than
the
corresponding
complex
Pd2
naphthalene
a. Polydispersity
not
active
in the
(Table
2,
entry
11).
Entry
Catalyst
Pcopolymerization
(bar)2. Ethylene
T ( C)
Comonomer
[M]
mol/L by
Activity
X complexes
(%)with
M the
Table
copolymerization
catalyzed
Pd(II)
and
Ni(II)
Yield
backbone
(Table
2,
entries
9
and
10).
Moreover,
the
nickel
complex
Ni1″
with
benzene
backbone
is
(mg)
not
inNi1”
the
(Table
2, entry
11).
Entry
Catalyst
P copolymerization
(bar)
T (80
C)
Comonomer
[M]
mol/L
X complexes
M
Pd1
1.2
500
25
3(%)
1000 a. Polydispersity
1.19
1active
Yield
Table
2. Ethylene
copolymerization
catalyzed
by
Pd(II)Activity
and
nickel complex
benzene
backbone
isnickel
not
active
inNi(II)
the
copolymerization
backbone
(Table
2,99with
entries
9 and
10).
Moreover,
the
complex
backbone
is(Table 2, entry 11).
Pd1
1.2
500
25Ni1″X with
3(%) benzene
1000
1.19
1active
Entry
Catalyst
(bar)
T 80
( C)
Comonomer
[M]11).
mol/L (mg)
Activity
M a Polydispersity
not
in thePcopolymerization
(Table 2, entry
o
o
b
b
c
c
o
b
c
o
b
c
o
b
c
wd
wd
wd
d
d
wd
wd
d
Table 2. Ethylene copolymerization catalyzed by
Pd(II) and Ni(II) complexes .
Yield
d
d
(mg)
b X c3
Pd1
1.2
500
25 Ni(II)
1active
9 2. Ethylene
Entry
Catalyst
Pcopolymerization
(bar)
T 80
(oC)
Comonomer
[M]
mol/L by
(%) 1000
Mw d a.
not
in the
(Table 2, entry
11).
Table
copolymerization
catalyzed
Pd(II)Activity
and
complexes
Yield
(mg)
d
1.19
Polydispersity
b X c3(%)
d
Pd1
1.2
500
25
1000
1.19
12
99 2. Ethylene
Entry
Catalyst
P (bar)
T 80
(oC)
Comonomer
[M]
mol/L by
M
w d a. Polydispersity
Pd2 Table
1.2
340
17 Ni(II)
5
4400
1.92
80
Yield
copolymerization
catalyzed
Pd(II)Activity
and
complexes
(mg)
d
o
b
c
d
a.
Pd1
1.2
500
25
3
1000
1.19
1
9
80
Entry
Catalyst
P (bar)
T ( C)
Comonomer
[M] mol/L
X complexes
Mw
Pd2
a. Polydispersity
340
17 Ni(II)
5(%)
1.92
2
Table
2.
Ethylene
copolymerization
catalyzed
by
Pd(II)
and4400
Ni(II)
complexes
Table
2.
Ethylene
copolymerization
catalyzed
by
Pd(II)Activity
and
Yield
(mg)
d
Pd1 P (bar)
500
25 b X c53(%) 4400
1000
1.19
Pd2
340
17
1.92
21
9
Entry
Catalyst
T 80
(oC)
Comonomer
[M]1.2
mol/L Yield
Activity
Mw d
Polydispersity
(mg)
oC)
d
Pd1
500
25
1000
1.19
Pd2
340
17
53(%) 4400
1.92
213
99
Entry
Catalyst
T 80
(80
Comonomer
[M]1.2
mol/L Yield
Activity
M
wd
Polydispersity
Pd3 P (bar)
1.2
950
47 b X c15
5500
1.55
d
oC)
d
Pd1
1.2
500
25
35(%) M
1000
1.19
Pd2 P (bar)
340
17 b X c15
4400
1.92
Entry
Catalyst
T 80
(80
Comonomer
[M] 1.2
mol/L (mg)
Activity
Polydispersity
Pd3
950
47
5500
1.55
312
99
bw
Entry
T 80
(o C)
Comonomer
[M]
X c (%)1.55
Activity
Polydispersity d
Pd1 P (bar)
1.2mol/L (mg)
500Yield (mg)
25
1000
1.19 Mw d
80
Pd2
340
17
53
4400
1.92
Pd3
1.2
950
47
15
5500
321Catalyst
99
Pd1
500
25
358
1000
1.19
Pd2
340
17
4400
1.92
Pd3
1.2
950
47
15
5500
1.55
3124
99
80
Pd1
2.5
200
10
1600
1.43
80
Pd2
1.2
500
385 25 1000
1423 Pd1 Pd1
80
340
17
4400
1.92
Pd3
950 500 25
47
15
5500
1.55 1000
1
999
80
1.2
3 1.19
1.19
Pd1
2.5
200
10
1600
1.43
80
Pd2
340
17
4400
1.92
80
Pd3
1.2
950
47
15
5500
1.55
Pd1
2.5
200
10
85
1600
1.43
432
99
80
Pd2
1.2
340
17
5
4400
1.92
2
9
80
Pd3
950
47
15
5500
1.55
1.2
5 1.43
1.92
2
99
80
2.5
200
8 17 1600
435 Pd2 Pd1
Pd2
2.5
300 340 10
15
12
2100
1.35 4400
80
Pd2
Pd3
1.2
340
17
58
4400
1.92
2534
99
80
950
47
15
5500
1.55
Pd1
200
10
1600
1.43
Pd2
2.5
300
15
12
2100
1.35
80
Pd3
1.2
950 950 15
47
15
5500
1.55 5500
80
Pd1
200
10
8 47 2100
1600
1.43
3
9 99
80
1.2
15 1.35
1.55
2.5
300
12
543 Pd3 Pd2
80
Pd3
1.2
950
47
15
5500
1.55
99
80
Pd1
200
10
8
1600
1.43
Pd2
2.5
300
15
12
2100
1.35
5346
Pd3
2.5
510
25
27
3600
1.58
80
Pd1
1.2
950
15
3645 Pd1 Pd3
80
2.5
200
10
8 10 5500
1600
1.43
Pd2
300 200 47
15
12
2100
1.35 1600
4
999
80
2.5
8 1.55
1.43
Pd3
2.5
510
25
27
3600
1.58
80
Pd1
2.5
200
10
8
1600
1.43
80
Pd2
300
15
12
2100
1.35
Pd3
2.5
510
25
27
3600
1.58
654
99
80
Pd1
2.5
200
10
8
1600
1.43
4
9
80
Pd2
300
15
12 15 61,500
2100
1.35
510
25
27
3600
657 Pd2 Pd3
5
99
80
2.5
12 1.58
1.35
Ni3
1.0
150 300 7.5
1.5
2.64 2100
25
Pd1
Pd2
2.5
200
10
8
1600
1.43
4756
99
80
300
15
12
2100
1.35
Pd3
510
25
27
3600
1.58
Ni3
1.0
150
7.5
1.5
61,500
2.64
25
Pd2
300 5107.5
15
12 25 61,500
2100
1.35 3600
2.5
510
25
27
3600
1.58
80
Ni3
1.0
150
1.5
765 Pd3 Pd3
25
6
9 99
80
2.5
27 2.64
1.58
Pd2
2.5
300
15
12
2100
1.35
99
80
Pd3
510
25
27
3600
1.58
Ni3
1.0
150
7.5
1.5
61,500
2.64
7568
25
Ni3
1.0
500
25
0.5
124,600
2.25
25
Pd3
2.5
300
15
12
2100
5867 Ni3 Pd2
80
510
25
277.5 124,600
3600
1.58
150 150 7.5
1.5
61,500
2.64 61,500
Ni3
1.0
500
25
0.5
2.25
25
1.0
1.5 1.35
2.64
7
999
25
Pd3
2.5
510
25
27
3600
1.58
80
150
7.5
1.5
61,500
2.64
Ni3
1.0
500
25
0.5
124,600
2.25
876
99
25
Pd3
2.5
510
25
27
3600
1.58
6
9
80
Ni3
1.0
150
7.5
1.5
61,500
2.64
7
25
500
0.5
89 Ni3 Pd2″
8
99
25
1.0
0.5 2.25
2.25
1.2
110 500 5.5
2.525 124,600
1950
1.95 124,600
25
Pd3
Ni3
2.5
510
25
27
3600
1.58
6978
99
80
1.0
150
7.5
1.5
61,500
2.64
25
500
0.5
124,600
2.25
Pd2″
1.2
110
5.5
2.5
1950
1.95
25
Ni3
150 1105.5
7.5
1.55.5 124,600
61,500
2.64 1950
25
1.0
500
25
0.5
2.25
1.2
110
2.5
1950
987 Pd2”Pd2″
25
9
9 99
25
1.2
2.5 1.95
1.95
Ni3
1.0
150
7.5
1.5
61,500
2.64
500
25
0.5
124,600
2.25
Pd2″
1.2
110
5.5
2.5
1950
1.95
978
99
25
Pd2″
2.5
80
4
6
1100
1.63
10
25
Ni3
1.0
150
1.5
61,500
789
25
500
25
0.5
2.25
1.2
110
5.5
2.5
1950
1.95 1100
2.5
80
4
6 4 124,600
1100
1.63
10
25
10
Pd2”Pd2″
999
25
2.5
80 7.5
6 2.64
1.63
Ni3
1.0
500
25
0.5
124,600
2.25
8
9
25
1.2
110
5.5
2.5
1950
1.95
9
Pd2″
2.5
80
4
6
1100
1.63
10
9
25
Ni3
1.0
500
25
0.5
2.25
89
1.2
110
5.5
2.5
1950
1.95
Pd2″
2.5
80
40
6- 0 124,600
1100
1.63
10
99
25
Ni1″
1.0
0
11
25
1.0
0
11
Ni1”
9
25
Ni3
Pd2″
1.0
500
25
0.5
124,600
2.25
89
99
25
1.2
110
5.5
2.5
1950
1.95
2.5
80
61100
1.63
10
Ni1″
1.0
0
04
11
25
1.2
110
5.5
2.5
1950
1.95
9
Pd2″
2.5
80
61100
1.63
10
9
25
Ni1″
1.0
0
04
11
a Polymerization
b
a Polymerization conditions: total volume toluene + polar monomer = 25 mL, catalyst = 20 μmol.
+ polar110
monomer
mL,
catalyst
= 201.95
Pd2″
1.2
5.5
1950
9 a
2.5
80
61100
1.63
10
Ni1″ conditions:
0
04 = 252.5
-µmol. Activity in unit
11
9
25 total volume toluene 1.0
Polymerization
conditions:
total
volume toluene1.2
25 mL,
catalyst
= 20 1μmol.
−1 ·hin
−1unit
Pd2″
110
5.5
2.5
1950
9gab·mol
2.5
80
40 =%),
6- (mol
1100
1.63
Ni1″
1.0+ polar
0monomer
- determined
11
−1
−1. c monomer
Activity
of 102533 g·mol
·h−1
Amount
of polar
monomer
incorporated
%),
of 10310
.9 c Amount
oftotal
polar
incorporated
(mol
H1.95
NMR
spectroscopy (see
Polymerization
volume
toluene
+ polar
monomer
= 25 determined
mL,
catalyst
=by
20 μmol.
−1
c
Pd2″
2.5
80
4
6
1100
1.63
10 ab Activity
Ni1″ in unit
1.0
0
0
11
9 conditions:
25
of 10 g·moltotal
·h .volume
Amount
of polar
monomer
incorporated
(mol
%), determined
dtoluene
◦ C (see Supplementary
1H NMR spectroscopy
Polymerization
conditions:
+ polar
monomer
=trichlorobenzene
25 dmL,
catalyst
=by
20
μmol.
3 g·mol
−1Supplementary
−1. c Amount
(see
Materials,
Figures
S21–S25).
Determined
GPC
in
Supplementary
Materials,
Figures
S21–S25).
Determined
by
GPC
in
at
150
Pd2″
2.5
80
4
6
1100
1.63
10
9
25
Activity
in
unit
of
10
·h
of
polar
monomer
incorporated
(mol
%),
determined
Ni1″
1.0
0
0
11 baby
1H NMR spectroscopy
Polymerization
conditions:
volume toluene
+ polar
monomer
= 25 dmL,
catalyst
=by20GPC
μmol.
(seetotal
Materials,
Figures
S21–S25).
Determined
3 g·mol
−1Supplementary
−1. c Amount of
Pd2″
Ni1″ in unit
2.5
80
40
6- (mol1100
1.63
10
9 at
1.0 monomer
0
- determined
-in
11 bby
Activity
of
1025
·h
polar
incorporated
%),
atrichlorobenzene
1H
150
°C(see
(seetotal
Supplementary
Materials,
Figures
S49–S56).
Materials,
Figures
S49–S56).
Polymerization
conditions:
toluene
+ polar
monomer
= 25 dmL,
catalyst
=by20GPC
μmol.
NMR
Materials,
Figures
S21–S25).
Determined
b Activity
3 g·mol
−1Supplementary
c Amount
in spectroscopy
unit
of150
1025
·h−1.volume
of
polar
incorporated
Ni1″
1.0 monomer
0
0
- (mol %),
- determined
-in
11 aby
9 at
trichlorobenzene
°C(see
(seetotal
Supplementary
Materials,
Figures
S49–S56).
1H NMR spectroscopy
dmL,
Polymerization
conditions:
volume
toluene
+
polar
monomer
=
25
catalyst
=
20
μmol.
Supplementary
Materials,
Figures
S21–S25).
Determined
by
GPC
by
b Activity
3
−1
−1
c
in spectroscopy
unit
of150
1025°C
g·mol
·h .volume
Amount
of
polar
monomer
incorporated
%),
Ni1″
1.0+ polar
0monomer
0 = 25 dmL,
- (mol
- determined
-in
11 trichlorobenzene
9 at
(seetotal
Supplementary
Materials,
Figures
S49–S56).
a Polymerization
1H
conditions:
toluene
catalyst
=by
20GPC
μmol.
NMR
(see
Supplementary
Materials,
Figures
S21–S25).
Determined
in the
by
Clearly,
great
enhancement
in
the
polymerization
properties
was
achieved
by
changing
b
3
−1
−1
c
1.0 monomer
0
0 was dachieved
- (mol %),
- by
11 trichlorobenzene
9 enhancement
in unit
of150
1025°C
g·mol
·hin . the
Amount
of
polar
incorporated
determined
at
(see Supplementary
Materials,
Figures
S49–S56).
a Activity
1 Ni1″ great
Clearly,
polymerization
properties
changing
the
Polymerization
conditions:
toluene
+ polar
monomer
= 25 mL,
catalyst
=by20GPC
μmol.
H NMR
(see
Materials,
Figures
S21–S25).
Determined
in
by
−1Supplementary
c Amount
Activity
in spectroscopy
unit at
of150
103 °C
g·mol
·h−1.volume
of
polar
monomer
incorporated
(mol
%), determined
trichlorobenzene
(seetotal
Supplementary
Materials,
Figures
S49–S56).
b
ligand
backbone
from
benzene
toinnaphthalene
(Scheme
3).
Ligand
electronic
effect
may
play
an
aClearly,
1H NMR
great
enhancement
the
polymerization
properties
was
achieved
by=by
changing
conditions:
total
toluene
+ polar
monomer
= electronic
25 dmL,
catalyst
20GPC
μmol.
spectroscopy
(see
Materials,
Figures
S21–S25).
Determined
inbythe
by
b Polymerization
3 °C
−1Supplementary
−1.volume
c Amount
Clearly,
greatgreat
in
the
polymerization
properties
was
achieved
changing the ligand
ligand
backbone
from
benzene
to
(Scheme
3).
Ligand
effect
may
play
an
Activity
inenhancement
unit
of150
10
g·mol
·h
of
polar
monomer
incorporated
(mol
%),
trichlorobenzene
at
(see
Supplementary
Materials,
Figures
S49–S56).
1H NMR
aClearly,
enhancement
in−1naphthalene
the
polymerization
properties
was
achieved
bydetermined
changing
the
spectroscopy
(see
Materials,
Figures
S21–S25).
Determined
GPC
inacidic
Polymerization
conditions:
total
volume
toluene
+ polar
monomer
= electronic
25 dmL,
catalyst
=by
20more
μmol.
important
role.
1-Naphthalenesulfonic
acid
(pKa
=
0.17
at
298
K
in
aqueous
solution)
is
bby
3 g·mol
−1Supplementary
c Amount
ligand
backbone
from
benzene
to
naphthalene
(Scheme
3).
Ligand
effect
may
play
an
Activity
in
unit
of
10
·h
.
of
polar
monomer
incorporated
(mol
%),
determined
trichlorobenzene
at 150 °C(see
(see Supplementary
Supplementary
Materials,
Figures
S49–S56).
1H NMR
Clearly,
great
enhancement
in
the
polymerization
properties
was dachieved
byby
the
important
role.
1-Naphthalenesulfonic
acid
(pKa
= 0.17monomer
at
298Ligand
Kincorporated
in aqueous
solution)
ischanging
more
acidic
spectroscopy
Materials,
Figures
S21–S25).
Determined
GPCplay
in
by
btrichlorobenzene
3 °C
−1to
−1naphthalene
c Amount
ligand
backbone
from
benzene
(Scheme
3).
Ligand
electronic
effect
may
an
backbone
from
benzene
to
naphthalene
(Scheme
3).
electronic
effect
may
play an important
at
150
(see
Supplementary
Materials,
Figures
S49–S56).
Activity
in
unit
of
10
g·mol
·h
.
of
polar
(mol
%),
determined
than
benzenesulfonic
acid
(pKa
=
0.70
at
298
K
in
aqueous
solution)
[52],
suggesting
that
Clearly,
great
enhancement
in
the
polymerization
properties
was
achieved
by
changing
the
1
d
important
role. 1-Naphthalenesulfonic
acid (pKa
= 0.17 at
298
KS21–S25).
in aqueous
solution)
ismay
more
H NMR
spectroscopy
(see
Supplementary
Materials,
Figures
Determined
by
GPCplay
inacidic
by
ligand
backbone
from
benzene
to
naphthalene
(Scheme
3). Ligand
electronic
effect
an
trichlorobenzene
at 150
°C(see
(see
Supplementary
Materials,
Figures
S49–S56).
than
benzenesulfonic
acid
(pKa
0.70
at
298
K inat
aqueous
solution)
[52],
suggesting
that
1H NMR
dachieved
Clearly,
great
enhancement
in=naphthalene
the
polymerization
properties
was
by
changing
the
important
role.
1-Naphthalenesulfonic
acid
(pKa
= 0.17
298
KS21–S25).
inthan
aqueous
solution)
is
more
spectroscopy
Supplementary
Materials,
Figures
Determined
by
GPCplay
inacidic
by
naphthalene
based
ligand
is
electronically
more
withdrawing
the
benzene
based
ligand.
ligand
backbone
from
benzene
to
(Scheme
3).
Ligand
electronic
effect
may
an
than
benzenesulfonic
acid
(pKa
=
0.70
at
298
K
in
aqueous
solution)
[52],
suggesting
that
role. 1-Naphthalenesulfonic
acid
(pKa
=
0.17
at
298
K
in
aqueous
solution)
is
trichlorobenzene
at
150
°C
(see
Supplementary
Materials,
Figures
S49–S56).
Clearly,
great
enhancement
in theacid
polymerization
wasthe
achieved
by based
the more acidic than
important
role.
1-Naphthalenesulfonic
(pKa
= 0.17
atproperties
298 K inthan
aqueous
solution)
ischanging
more
acidic
naphthalene
based
ligand
is(pKa
electronically
more
withdrawing
benzene
ligand.
ligand
backbone
from
benzene
to
(Scheme
3).
electronic
effect
may
play
an
than
benzenesulfonic
acid
0.70
at(pKa
298
inatFigures
aqueous
solution)
[52],
suggesting
that
trichlorobenzene
at
150
°C
Supplementary
Materials,
S49–S56).
Clearly,
enhancement
in=naphthalene
the
polymerization
properties
was
achieved
by
the
Moreover,
thegreat
bigger
size
ofis(see
the
naphthalene
backbone
may
help
to
prevent
catalyst
deactivation
important
role.
1-Naphthalenesulfonic
acid
=K
0.17
298Ligand
K
inthan
aqueous
solution)
ischanging
more
acidic
naphthalene
based
ligand
electronically
more
withdrawing
the
benzene
based
ligand.
ligand
backbone
from
benzene
to
naphthalene
(Scheme
3).
Ligand
electronic
effect
may
play
annaphthalene based
than
benzenesulfonic
acid
(pKa
=
0.70
at
298
K
in
aqueous
solution)
[52],
suggesting
that
benzenesulfonic
acid
(pKa
0.70
atnaphthalene
298
K(pKa
in
aqueous
solution)
[52],
suggesting
that
Moreover,
the
bigger
size=ofis
the
naphthalene
backbone
may
help
to
prevent
catalyst
deactivation
Clearly,
great
enhancement
in
the
polymerization
was
achieved
by based
the
important
role.
1-Naphthalenesulfonic
acid
= 0.17
atproperties
298
K
inthan
aqueous
solution)
ischanging
more
acidic
naphthalene
based
ligand
electronically
more
withdrawing
the
benzene
ligand.
ligand
backbone
from
benzene
to
(Scheme
3).
Ligand
electronic
effect
may
play
an
reactions
such
as
bis-ligation
[53].
Furthermore,
the
potential
interaction
of
the
hydrogen
atom
on
than
benzenesulfonic
acid
(pKa
=
0.70
at
298
K
in
aqueous
solution)
[52],
suggesting
that
Moreover,
the
bigger
size
of
the
naphthalene
backbone
may
help
to
prevent
catalyst
deactivation
Clearly,
great
enhancement
inFurthermore,
theacid
polymerization
wasthe
achieved
by is
changing
the
important
role.
1-Naphthalenesulfonic
(pKa
= 0.17
atproperties
298Ligand
K
inthan
aqueous
solution)
more
acidic
naphthalene
based
ligand
is
electronically
more
withdrawing
benzene
based
ligand.
reactions
such
as
bis-ligation
[53].
the
potential
interaction
of
the
hydrogen
atom
on
ligand
backbone
from
benzene
to
naphthalene
(Scheme
3).
electronic
effect
may
play
an
than
acidofis
(pKa
= 0.70
298
Kwithdrawing
in
aqueous
solution)
[52],
suggesting
that the bigger size of
Moreover,
thebased
bigger
size
the
naphthalene
backbone
help
tosulfonate
prevent
catalyst
deactivation
ligand is
more
withdrawing
than
the
benzene
based
ligand.
Moreover,
important
role.
1-Naphthalenesulfonic
acidat
(pKa
=the
0.17
atmay
298Ligand
K
inor
aqueous
ismay
more
acidic
theelectronically
8 benzenesulfonic
position
of
the
naphthalene
backbone
with
phosphine
substituent
may
also
naphthalene
ligand
electronically
more
than
theof solution)
benzene
based
ligand.
reactions
such
as
bis-ligation
[53].
Furthermore,
the
potential
interaction
the
hydrogen
atom
on
ligand
backbone
from
benzene
to
naphthalene
(Scheme
3).
electronic
effect
play
an
than
benzenesulfonic
acid
(pKa
=
0.70
at
298
K
in
aqueous
solution)
[52],
suggesting
that
Moreover,
the
bigger
size
of
the
naphthalene
backbone
may
help
to
prevent
catalyst
deactivation
the
8 position
of
the
naphthalene
backbone
with
phosphine
sulfonate
substituent
may
also
important
role.
1-Naphthalenesulfonic
acidat
(pKa
=the
0.17
at aqueous
298 K
inor
aqueous
solution)
is
more
acidic
naphthalene
based
ligand
electronically
more
than
the
benzene
based
ligand.
reactions
such
as
bis-ligation
[53].
Furthermore,
the
potential
interaction
the
hydrogen
atom
onas bis-ligation [53].
than
benzenesulfonic
acid
= 0.70
298
Kwithdrawing
inat
solution)
[52],
suggesting
that
influence
the
catalyst
properties.
This
steric
effect
may
bemay
the help
key
factor
inofthe
differences
between
Moreover,
the
bigger
size
ofis(pKa
the
naphthalene
backbone
tosulfonate
prevent
catalyst
deactivation
the
8 position
of
the
naphthalene
backbone
with
phosphine
substituent
may
also
the naphthalene
backbone
may
help
to
prevent
catalyst
deactivation
reactions
such
important
role.
1-Naphthalenesulfonic
acid
(pKa
=the
0.17
298
inor
aqueous
solution)
is
more
acidic
naphthalene
based
ligand
electronically
more
than
the
benzene
based
ligand.
reactions
such
as
bis-ligation
[53].
Furthermore,
the
potential
interaction
the
hydrogen
atom
on
influence
the
catalyst
properties.
This
steric
may
the K
key
factor
inofthe
differences
between
than
benzenesulfonic
acidofis
(pKa
= 0.70
ateffect
298
Kwithdrawing
inbemay
aqueous
solution)
[52],
suggesting
that
Moreover,
the
bigger
size
the
naphthalene
backbone
help
to
prevent
catalyst
deactivation
the
8
position
of
the
naphthalene
backbone
with
the
phosphine
or
sulfonate
substituent
may
also
naphthalene
based
ligand
is
electronically
more
withdrawing
than
the
benzene
based
ligand.
the two
sets
ofcatalyst
catalysts
with
different
connectivity
topotential
the
naphthalene
backbone.
reactions
such
as the
bis-ligation
[53].This
Furthermore,
the
interaction
ofthe
the
hydrogen
atomthat
on
influence
the
properties.
steric
effect
may
be
the
key
factor
in
differences
between
than
benzenesulfonic
acid
(pKa
=
0.70
at
298
K
in
aqueous
solution)
[52],
suggesting
Moreover,
the
bigger
size
of
the
naphthalene
backbone
may
help
to
prevent
catalyst
deactivation
the
8
position
of
naphthalene
backbone
with
the
phosphine
or
sulfonate
substituent
may
also
Furthermore,
the
potential
interaction
of
the
hydrogen
atom
on
the
8
position
of the naphthalene
the
two
sets
of
catalysts
with
different
connectivity
to
the
naphthalene
backbone.
naphthalene
based
ligand
is
electronically
more
withdrawing
than
the
benzene
based
ligand.
reactions
such
as
bis-ligation
[53].
Furthermore,
the
potential
interaction
of
the
hydrogen
atom
on
influence
the
catalyst
properties.
This
steric effect
may
bemay
the key
factor
in thesubstituent
differences
between
Moreover,
the
bigger
size
ofisdifferent
the
naphthalene
backbone
help
tosulfonate
prevent
catalyst
deactivation
8 position
of
the
naphthalene
backbone
with
the
phosphine
or
may
also
the
two
sets
ofbased
catalysts
with
connectivity
to
the
naphthalene
backbone.
naphthalene
ligand
electronically
more
withdrawing
than
the
benzene
based
ligand.
reactions
such
as
bis-ligation
[53].
Furthermore,
the
potential
interaction
the
hydrogen
atom
on
influence
the
catalyst
properties.
This
steric effect
may
bemay
the help
key
factor
inofthe
differences
between
Moreover,
the
bigger
size
of different
the
naphthalene
backbone
tosulfonate
prevent
catalyst
deactivation
8
position
of
the
naphthalene
backbone
with
the
phosphine
or
substituent
may
also
the
two
sets
of
catalysts
with
connectivity
to
the
naphthalene
backbone.
backbone
with
the
phosphine
or
sulfonate
substituent
may
also
influence
the
catalyst properties.
reactions
such
as
bis-ligation
[53].
Furthermore,
the
potential
interaction
of
the
hydrogen
atom
on
influence
the
catalyst
properties.
steric effect
may
bemay
the help
keyorfactor
in thesubstituent
differences
between
Moreover,
the
bigger
size
of different
the This
naphthalene
backbone
tosulfonate
prevent
catalyst
deactivation
the two
8 position
of
naphthalene
backbone
with
the
phosphine
also
sets
ofcatalyst
catalysts
with
connectivity
topotential
the
naphthalene
backbone.
reactions
such
as the
bis-ligation
[53].This
Furthermore,
the
interaction
the
hydrogenmay
atom
on
influence
theof
properties.
steric effect
may
benaphthalene
the key
factor
inofthe
differences
between
8
position
of
the
naphthalene
backbone
with
the
phosphine
or
sulfonate
substituent
may
also
the
two
sets
catalysts
with
different
connectivity
to
the
backbone.
This steric
effect
be properties.
the key
factor
in the
differences
between
the
sets may
of
catalysts
with different
reactions
such
as bis-ligation
[53].
Furthermore,
the
potential
interaction
thetwo
hydrogen
atom
on
influence
themay
catalyst
This
steric
effect
may
be the key
inof
the
differences
between
the
8 position
of
the naphthalene
backbone
with the
phosphine
orfactor
sulfonate
substituent
also
two
sets
catalysts
with different
connectivity
to the
backbone.
influence
theof
catalyst
properties.
This
steric effect
may
benaphthalene
the keyor
factor
in thesubstituent
differencesmay
between
8 position
of
the naphthalene
backbone
with the
phosphine
sulfonate
also
two
sets
ofcatalyst
catalysts
with different
connectivity
to the
naphthalene
backbone.
connectivity
to
the
naphthalene
backbone.
Polymersthe
2017,
9,
168
6 of 8
influence
the
properties.
This
steric
effect
may
be
the
key
factor
in
the
differences
between
the two sets of catalysts with different connectivity to the naphthalene backbone.
influence the catalyst properties. This steric effect may be the key factor in the differences between
the two sets of catalysts with different connectivity to the naphthalene backbone.
the two sets of catalysts with different connectivity to the naphthalene backbone.
Scheme 3. Comparison of the three ligand frameworks.
3. Conclusions
To conclude, a series of phosphine-sulfonate based palladium and nickel catalysts were
prepared and characterized. A naphthalene bridge was installed in the ligand framework. These
palladium and nickel catalysts showed very high activities in ethylene polymerization. For the case
Polymers 2017, 9, 168
6 of 9
3. Conclusions
To conclude, a series of phosphine-sulfonate based palladium and nickel catalysts were prepared
and characterized. A naphthalene bridge was installed in the ligand framework. These palladium
and nickel catalysts showed very high activities in ethylene polymerization. For the case of nickel
system, very high polyethylene molecular weights could be achieved. Both the palladium and the
nickel catalysts could initiate ethylene-polar monomer copolymerization. We clearly demonstrated
the importance of ligand backbone structure and connectivity in determining the properties of these
metal catalysts. This work provides an alternative strategy to modify/improve the properties of
group 10 phosphine-sulfonate catalysts.
Supplementary Materials: The following are available online at www.mdpi.com/2073-4360/9/5/168/s1.
Experimental procedures, characterization for ligands, palladium complexes, nickel complexes (Figures S1–S20),
polyethylene and copolymers (Figures S21–S56), and CIF files for complexes Pd2 and Ni1.
Acknowledgments: This work was supported by National Natural Science Foundation of China (NSFC, 21690071,
and 51522306), the Fundamental Research Funds for the Central Universities (WK3450000001), and the Recruitment
Program of Global Experts.
Author Contributions: Changle Chen conceived and designed the experiments; Zixia Wu, Changwen Hong,
Hongxu Du, and Wenmin Pang performed the experiments; and Zixia Wu and Changle Chen analyzed the data
and wrote the paper.
Conflicts of Interest: The authors declare no conflict of interest.
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