1 macromolecular science and engineering wednesday june 2 ma3 regatta advances in olefin...
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1
Macromolecular Science and Engineering
Wednesday June 2 MA3 Regatta Advances In Olefin Polymerization
Organizer - H. Zahalka Chair - J. Soares
14:00-14:30 00995 A Density Functional Study on Ion-Pair Formation in Group 4 Metallocene and Related Olefin Polymerization CatalystsZiegler T., Chan M., Vanka K., Pye C.
2
A Density Functional Study on Activation and Ion-Pair Formation in Group IV Metallocene and Related Olefin
Polymerization Catalysts
Mary S.W. Chan, Kumar Vanka, Cory C. Pye and Tom Ziegler
Department of Chemistry, University of CalgaryCalgary, Alberta Canada T2N 1N4
Ion-Pair FormationCH3
Zr
CH3
CH3
CH3
CH3
CH3
B
C6
F5
C6F5
C6F5
CH3
Zr
CH3
CH3
CH3
CH3
CH3
B
C6F5
C6F5
C6F5
Ion-Pair Formation
P.Deck,T.Marks, J.Am.Chem.Soc. 1995,117,6128-6129
ΔH dr . = -23.8 / , calc KCal molΔHdr . = -24.2 /exp KCal mol
F
F
C
F
C
C
C
C
C
F
C
F
F
C
C
F
C
C
F
C
C
B
C
C
C
C
C
Zr
C
C
CC
F
C
C
C
C
C
F
C
C
F
C
C
F
C
C
C
F
F
F
5
Major SectionsMajor Sections
Mono-cyclopentadienyl
ConstrainedGeometry
Bis-cyclopentadienyl
MR R
RNR
RRR2Si M R
RM M = Ti or Zr
R = methyl group
Reactions of the contact ion-pair
Activation of various catalyst precursors by the co-catalyst B(C6F5)3
Areas for In-depth Study
Catalyst Systems for In-depth Study
6
Enthalpy Change of Methide Abstraction
H3C CH3H3C
B
C6F5
C6F5C6F5
H3C
CH3CH3
B
C6F5
C6F5
C6F5+M
N
CH3CH3
H2Si
H
B
C6F5
C6F5C6F5
N
CH3CH3
H2Si
HB
C6F5
C6F5
C6F5+M
M
CH3CH3
B
C6F5
C6F5C6F5 CH3
CH3B
C6F5
C6F5
C6F5+M
M
∆H M = Ti -12.2 kcal/mol M = Zr -14.9 kcal/mol
∆H M = Ti -14.4 kcal/mol M = Zr -17.5 kcal/mol
∆H M = Ti -16.3 kcal/mol M = Zr -19.1 kcal/mol
Activation by a Activation by a Co-catalyst-catalyst
7
Activation by a Co-catalystActivation by a Co-catalyst
Charge Analysis of Ligands and Functional Groups in the Neutral Precursor and Ion-Pair
+
Cyclopentadienyl 0.02Ti 0.41methyl -0.15methyl -0.15methyl -0.13
B 0.11C6F5 -0.04C6F5 -0.03C6F5 -0.04
Cyclopentadienyl 0.13Ti 0.43methyl -0.07Methyl -0.07-methyl -0.03B -0.01C6F5 -0.09C6F5 -0.13C6F5 -0.15
C
C
C
C
Ti
C
CC
C
F
F
C
F
C
C
C
C
F
C
FF
FC
B
CC
C
C
F
F
C
C
C
C
Ti
C
C
C
C
F
C
C
F
C
C
C
C
F
F
C
F
FF
F
C
F
C
C
C
C
F
F
C
F
C
C
B
C
F
C
F
C
C
F
F
C
C
F
F
C
C
F
C
C
F
F
8
Activation by a Co-catalyst
N
CH3
CH3H2Si
R
B
C6F5
C6F5C6F5
N
CH3
CH3H2Si
RB
C6F5
C6F5
C6F5+TiTi
Effect of Alkyl Substitution on the Constrained Geometry Catalyst
∆H ∆H Total Total Change in R gas phase COSMO Charge in Charge in Charge
(kcal/mol) (kcal/mol) Neutral Ion-Pair Density
H -13.9 -14.4 -0.21 -0.17 0.04
Methyl -16.1 -16.4 -0.19 -0.13 0.06
Isopropyl -16.9 -17.0 -0.18 -0.12 0.06
tert-Butyl -18.4 -18.0 -0.19 -0.10 0.09
9
Activation by a Co-catalystActivation by a Co-catalyst
Effect of Methyl Substitution on Cp Rings
CH3
CH3
B
C6F5
C6F5C6F5
CH3
CH3
B
C6F5
C6F5
C6F5+Zr
Zr
∆H (kcal/mol) ∆H (kcal/mol) Substitution on Cp gas phase COSMO Experimentala
H -19.1 -19.1 -23.1
1,2-Dimethyl -23.8 -24.0 -24.3
Pentamethyl -27.5 -27.8 -36.7
aObtained from: Deck, P.A.; Beswick, C.L.; Marks, T.J. J. Chem. Soc. 1998, 120, 1772.
Co-catalyst Engineering
Co-catalyst ΔHdr . calc ΔHdrexp
/ /KCal mol KCal mol (B C6F5)3 -23.8 -24.2 (B C6F5)2(C6H3F2) -21.5 -18.7 (B C6F5)2 (C6H5) -18.3 -14.8 (B C6F5)2{C6H3(CH3)2} -18.0 -10.8 (B C6H5)3 -6.7 -- . . , . . , . . , . . . ,P A Deck C L Beswick T J Marks J Am Chem Soc
1998,120,1772-1784
5
10
15
20
25
-DelHdr
0 4 8 12 16 20
No. Of Fluorine Atoms
Plot Of -DelHdr vs No. of Fluorine Atoms
Charge AnalysisFunctional Group Δ . Hdrcalc Total Charge
/KCal mol C6F5 -23.8 -0.453
C6H3F2 -21.3 -0.3296
C6H5 -18.3 -0.2963
C6H3(CH3)2 -18.0 -0.2894
13
New Cocatalysts
L.Li, T.Marks, Organometallics 1998, 17, 3996-4003
F
F
C
F
C
C
F
C
C
C
C
F
F
C
C
F
C
C
CB
F
C
C
F
F
C
C
C
C
F
C
F
C
C
C
F
F
F
F
C
C
F
C
C
F
C
C
C
F
C
F
F
14
MAO as Co-catalyst
C
C
C
C
C
Al O
AlO
C
C
C
C
Zr
2.158Å
4.598Å Al
O
C
C
C
O
C
AlC
C
C
O
C
Al
C
C
OAl
C
C
C
C.J.Harlan, S.G.Bott, A.R.Barron,
J.Am.Chem.Soc. 1995,117,6465-6474
15
Co-catalyst ΔHdr . calc ΔHdrexp
( / ) ( / )KCal mol KCal mol(B C10F7)3 -25.8 -
-15.2 -10.9MAO -22.3 -MBO
AlMe3 -6.7 -(Al C6F5)3 -30.8 -
16
Ion-Pair DissociationCH3
Zr
CH3
CH3
CH3
CH3
CH3
B
C6F5
C6F5
C6F5
CH3
Zr
CH3
CH3
CH3
CH3
B
C6
F5 C6F5
CH3
C6F5
17
Ion-pair Dissociation Energies
Co-catalyst ΔHdr . -calc ΔHips . -calc ΔHipsexp#
/ / /KCal mol KCal mol KCal mol (B C6F5)3 -23.8 -38.0 -24.0(B C10F7)3 -25.8 -43.6 -
-15.2 -57.0 -MAO -22.2 -46.9 -MBOAlMe3 -6.7 -69.2 - (Al C6F5)3 -30.0 -48.3 -
18
Influence of Solvent
• Implicitly included through Single PointCalculations Using COSMO
• Explicitly included through addition of a singlesolvent molecule coordinated to the cation
19
Ion-Pair Dissociation
C6
F5
CH3
Zr
CH3
CH3
CH3
CH3
CH3
B
C6F5
C6F5
C6F5
CH3
Zr
CH3
CH3
CH3
CH3
B
C6F5
CH3
C6F5
CH3
CH3
Solvent Separated Ion-Pair
20
Influence Of Solvent
η2−Coordinated
F
F
C
C
F
F
C
F
C
F
C
C
C
C
F
F
C
C
C
B
C
C
C
C
C
F
C
C
C
C
CC
CF
F
C
C
F
Zr
C
C
C
C
C
C
C
C
C
F
C
C
CC
C
C
F
C
F
21
Influence Of Solvent
η1coordinated
F
F
C
C
F
C
C
F
C
C
C
C
CC
F
C
C
C
C
F
F
B
C
C
C
F
CZr
F
C
C
C
Cl
C
C
C
F
C
C
C
C
C
CC
F
C
C
F
C
C
F
C
F
C
C
C F
C
22
Solvent -ΔHips . -calc ΔHipsexp#
/ /KCal mol KCal mol (η2)C6H5CH3 -18.7 -24.2 (η2)C6D5 -15.4 -11.0Cl (η1)C6D5 -15.1 -11.0Cl (η2)C6D4Cl2 -13.8 -12.0 (η1)C6D4Cl2 -15.9 -12.0
. . , . . , . . ,P A Deck C L Beswick T J Marks. . . ., 1998,120,1772-1784J Am Chem Soc
23
Competing Reactions
CH3
Zr
CH3
CH3
CH3
Solvent
Precatalyst
Co-catalyst
Monomer
CH3
24
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
Zr
C
C
ZrC
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
25
Species ΔHdr
/KCal mol(1,2-Me2 )Cp 2ZrMe+-- (B C6F5)3 -9.9(1,2-Me2 )Cp 2ZrMe+--C6H5CH3 -10.2(1,2-Me2 )Cp 2ZrMe+--AlMe3 -25.4(1,2-Me2 )Cp 2ZrMe+--(1,2Me2 )Cp 2ZrMe2 -25.8
26
Work In Progress
Search for improved co-catalysts :
(i) Diborane Systems
L.Jia,X.Yang,C.Stern,T.J.Marks,
Organometallics,13,3755-37557
F
F
F
C
C
F
C
F
F
C
C
F
C
C
F
C
C
F
F C
F
F
BB
C
F
C
C
C
C
CC
F
C
C
C
C
F
F
C
C
F
C
F
F
C
C
C
C
F
27
Work In Progress
(ii) Modified MAO/MBO Structures
(iii) New Anionic systems- Carboranes,
M(OTeF5)nm- etc.
C
C
O
Al
Al
O
C
Al
O
O
Al
C
28
Work In Progress
PCH3
CH 3
Zr
CH 3
CH 3
CH 3
Solvent
Precatalyst
Monomer
29
IntroductionIntroduction
Possible Reactions of the Contact Ion-Pair{L}M
solvent complexed cation
Sol
solvent separated ion-pair
contact ion-pair
co-ordinatively unsaturated cation
olefin separated ion-pair
Me
{L}MMe
{L}MMe
{L}MMe
{L}MMe
{L}MMe
+
+
{L}M
+
Me
Me
olefin complexed cation
+ A
A
B
CD
EF
MeA
MeA
MeASol
MeA
precatalyst
MeA
MeA
30
-1.7 kcal/mol (-4.3)
-6.3 kcal/mol (3.4)
20.4 kcal/mol (50.5)
µ-Me contact ion-pair
solvated ion-pair
toluene separated ion-pair
toluene complexed cation
MeB(C6F5)3-+
+ CH3C6H5
Reactions of the Contact Ion-PairReactions of the Contact Ion-Pair
Toluene Complexed Ions and Ion-Pairs from the CpZrMe3 Precursor
C
C
C
C
C
C
C
C
ZrC
C
C
C
C
C
F
F
C
C
F
C
F
C
F
F
C
C
C
C
F
F
C
C
B
F
C
C
C
C
C
C
C
F
Zr
C
F
C
C
C
F
F
C
C
C
C
F
F
C
F
F
C
C
F
C
C
F
C
C
C
C
C
F
F
C
F
C
C
B
C
C
C
C
C
F
C
C
C
F
C
Zr
C
C
C
C
C
F
C
F
CC
C
C
F
C
F
C
F
F
F
F
F
F
C
C
F
F
C
C
C
C
C
C
F
C
CC
C
B
C
F
C
F
F
C
F
C
C
F
C
C
C
C
C
C
CZr
C
C
C
C
C
F
C
F
C
C
C
F
31
Reactions of the Contact Ion-PairReactions of the Contact Ion-Pair
Toluene Complexed Ions and Ion-Pairs from the H2SiCp(NH)ZrMe2 Precursor
11.5 kcal/mol (48.9)
-5.2 kcal/mol (-8.8)
0.0 kcal/mol (8.4)
µ-Me contact ion-pair
solvated ion-pair toluene separated ion-pair
toluene complexed cation
MeB(C6F5)3-+
+ CH3C6H5
+
C
N
C
Si
C
C
C
Zr
C
C
C
C
C
CC
C
F
F
C
F
C
C
C
C
F
F
C
F
F
F
Si
C
N B
C
C
C
C
C
C
C
F
Zr
C
C
C
C
C
F
C
C
F
C
C
C
F
F
C
F
F
F
F
C
C
F
C
C
C
F
C
C
C
C
F
F
F
C
C
F
B
C
N
C
C
F
Si
C
C
C
C
C
C
C
C
C
Zr
C
F
C
F
C
C C
F
F
C
C
C
F
C
F
C
C
F
C
C
F
C
C
C
C
Zr
C
F
C
C
C
F
C
C
C
N
Si
C
C
C
F
C
C
B
F
C
C
C
F
C
C
F
C
F
C
F
C
C
C
C
F
C
F
F
F
F
32
17.1 kcal/mol (33.4)
11.0 kcal/mol (32.5)
-2.5 kcal/mol (-4.2)
µ-Me contact ion-pair
solvated ion-pair
toluene separated ion-pair
toluene complexed cation
MeB(C6F5)3-+
+ CH3C6H5
+
Reactions of the Contact Ion-PairReactions of the Contact Ion-Pair
Toluene Complexed Ions and Ion-Pairs from the Cp2ZrMe2 Precursor
C C
C
C
C
C
C
C
CC
C
C
Zr
C
C
C
C
C
C
FC
F
F
C
CC
C
F
F
F
C
F
F
C
C
C
B
C
C
C
F
C
C
C
C
C
C
C
C
Zr
C
C
C
C
C
F
C
F
C
C
F
C
F
C
F
F
F C
F
F
C
C
C
C
F
F
C
F
C
F
C
F
C
B
C
C
C
F
C
C
C
C
C
C
CC
Zr
C
C
C
C
C
F
C
F
C
F
CC
F
C
C
C
F
C
C
F
C
C
C
FC
F
F
C
CC
C
F
F
C
F
F
C
B
F
C
C
C
C
C
C
F
C
CC
C
C
C
C
C
C
F
C
F
C
C
C
F
C
C
C
F
C
C
Zr
C
F
C
F
C CC
C
33
Reactions of the Contact Ion-PairReactions of the Contact Ion-Pair
Olefin Complexed Ions and Ion-Pairs from the CpZrMe3 Precursor
12.6 kcal/mol (20.0)
49.7 kcal/mol (94.8)
MeB(C6F5)3-
+
18.3 kcal/mol (51.9)
C2H4
µ-Me contact ion-pair
olefin separated ion-pair
olefin π-complex
co-ordinatively unsaturated cation
_
+
C2H4+
+
+
+
C
C
CC
Zr
C
CC
C
C
FF
C
C
C
C
FCCF
C
C
C
Zr
F
C
F
C
C
F
C
C
F
C
BC
CC
C
C
F
C
C
C
C
F
F
C
F
C
F
C
C
F
F
F
F
C
C
F
C
F
C
F
F
C
C
C
C
F
F
C
C
B
F
C
C
C
C
C
C
C
F
Zr
C
F
C
C
C
F
F
C
C
C
C
F
F
C
C
C
C
Zr
C
C
C
C
FF
F
F
C
C
F
F
C
C
CC
C
C
C
C
F
F
C
C
F
B
C
F
F
C
C
F
C
C
F
C
C
F
F
34
Reactions of the Contact Ion-PairReactions of the Contact Ion-Pair
Olefin Complexed Ions and Ion-Pairs from the H2SiCp(NH)ZrMe2 Precursor
10.0 kcal/mol (16.1)
49.8 kcal/mol (93.7)
20.0 kcal/mol (54.1)
µ-Me contact ion-pair
co-ordinatively unsaturated cation
olefin π-complex
olefin separated ion-pair
C2H4+ +
_+
MeB(C6F5)3-+
+
C2H4+
FF
F
F
C
C
F
F
C
C
CC
C
C
C
C
F
F
C
C
F
B
C
F
F
C
C
F
C
C
F
C
C
F
F
C
C
N
Si
C
Zr
C C
C C
C
F
C
F
C
C C
Si
N
C
FC
C
Zr
C
C
FC
F
C
C C
C
F
F
C
C
FB
C
C
C
C
F
C
C
C
F
C
C
F
F
C
C
F
F
F
F
F
C
F
C
C
C
C
F
F
C
F
F
F
Si
C
N B
C
C
C
C
C
C
C
F
Zr
C
C
C
C
C
F
C
C
F
C
C
C
F
F
C
F
F
C
C
N
C
Zr
Si
C
C
C
35
Reactions of the Contact Ion-PairReactions of the Contact Ion-Pair
Olefin Complexed Ions and Ion-Pairs from the Cp2ZrMe2 Precursor
48.5 kcal/mol (88.5)
20.4 kcal/mol (57.5)
8.2 kcal/mol (9.5)
co-ordinatively unsaturated cation
µ-Me contact ion-pair
olefin π-complex
olefin separated ion-pair
C2H4+ +
_
C2H4+
+
MeB(C6F5)3-+
+
FF
F
F
C
C
F
F
C
C
CC
C
C
C
C
F
F
C
C
F
B
C
F
F
C
C
F
C
C
F
C
C
F
F
C
C
C
C
C
Zr
C
C C
C
C
C
C
C
F
F
F
C
F
C
C F
FC
C
C
F
C
C C
CC
C
C
FB C F
C
C
CC F
FC
C
C
C
Zr
F
C
C
C
C
C
C
CC
F
C
C
F
F
FC
F
F
C
CC
C
F
F
F
C
F
F
C
C
C
B
C
C
C
F
C
C
C
C
C
C
C
C
Zr
C
C
C
C
C
F
C
F
C
C
F
C
F
C
F
F
C
C
C
C
C
CZr
C
C
C
C
C
36
Reactions of the Contact Ion-PairReactions of the Contact Ion-Pair
Initial Stages of Polymerization for CpMMe3 and H2SiCp(NH)MMe2 Systems
H3C
CH3CH3
B
C6F5
C6F5
C6F5
CH3B
C6F5
C6F5
C6F5
CH3
M
H3C
H3C
CH3B
C6F5
C6F5
C6F5
M
H3CH3C
CH2
CH2
H3C
CH3
CH3B
C6F5
C6F5
C6F5
CH3
M
M
H3C
CH2CH2CH3
CH3B
C6F5
C6F5
C6F5M
contact ion-pair
olefin separated ion-pair
toluene separated ion-pair
solvated ion-pair
olefin inserted product
37
Reactions of the Contact Ion-PairReactions of the Contact Ion-Pair
Initial Stages of Polymerization for Cp2MMe2 Systems
CH3CH3
B
C6F5
C6F5
C6F5
CH3B
C6F5
C6F5
C6F5
CH3
CH3
CH3B
C6F5
C6F5
C6F5
CH3
CH3B
C6F5
C6F5
C6F5CH2
CH2
M
M
M
M
CH2CH2CH3
CH3B
C6F5
C6F5
C6F5M
CH3
CH3
olefin separated ion-pair
olefin inserted product
contact ion-pair
toluene separated ion-pair
solvated ion-pair
38
Electronic factors play a predominant role in determining the enthalpy change of methide abstraction to form a contact ion-pair.
Mechanism of olefin complexation dependant on the structure of the catalyst precursor and solvent.
Mono-cyclopentadienyl and constrained geometry catalysts show a strong tendency to co-ordinate with toluene
The steric bulk of the bis-cyclopentadienyl catalysts prevent optimal co-ordination with toluene and makes olefin complexation more favorable
Conclusions
39
Work in ProgressWork in Progress
Search for the structure of resting state(s) incorporating the counter ion
Molecular dynamics simulation of olefin uptake and insertion from the contact ion-pair
F
F
C
C
F
C
C
F
C
C
C
CC
F
C
F
F
C
C
F
C
F
B
C
C
C
C
C
Zr C
C
C
C
C
C
C
C
F
C
F
F
C
F
F
C
C
F
C
C
C
40
Future WorkFuture Work
To study the influence of the counter ion on the propagation steps of the polymerization process
To study the influence of the counter ion on chain termination steps of the polymerization process
To study the role of the counter ion with other catalysts precursors such as the Brookhart or the McConville systems
To study the influence of other solvents (non-aromatic) on ion-pair formation and dissociation
To design new precatalysts and co-catalysts systems
NSERC
PRF Novacor
Dr. Mary Chan
Kumar Vanka
Dr. Cory Pye
42
43
Computerson benchesall linkedtogether
Cobalt
44