Bimetallic effects for enhanced polar comonomer enchainment selectivity in catalytic ethylene polymerization

Brandon A. Rodriguez; Massimiliano Delferro; Tobin J. Marks

doi:10.1021/ja900257k

Bimetallic effects for enhanced polar comonomer enchainment selectivity in catalytic ethylene polymerization

Brandon A. Rodriguez, Massimiliano Delferro, Tobin J. Marks

Chemistry

Research output: Contribution to journal › Article › peer-review

102 Scopus citations

Abstract

The synthesis and characterization of the bimetallic 2,7-di-[(2,6- diisopropylphenyl)imino]-1,8- naphthalenediolato group 10 metal polymerization catalysts {[Ni(CH ₃)] ₂[1,8-(O) ₂C ₁₀H ₄-2,7-[CH=N(2,6- Pr ₂C ₆H ₃)](PMe ₃) ₂} and {[Ni(1-naphthyl)] ₂[1,8-(O) ₂C ₁₀H ₄-2,7-[CH=N(2,6-Pr ₂C ₆H ₃)](PPh ₃) ₂} [FI ²-Ni ₂(PR ₃) ₂] are presented, along with the synthesis and characterization of the mononuclear analogues {Ni(CH ₃)[3- ^tBu- 2-(0)C ₆H ₃CH=N(2,6- ⁱPr ₂C ₆H ₃)](PMe) ₃}and{Ni(1-naphthyl)[3- ^tBu-2-(0)C ₆H ₃CH=N(2,6- ⁱPr ₂C ₆H ₃)](PPh) ₃}[FI- Ni (PR ₃)]. Monometallic Ni catalysts were also prepared by functionalizing one ligation center of the bimetallic ligand with a trimethylsilyl group (TMS), yielding {Ni(CH ₃)[1,8-(O)(TMSO)C ₁₀H ₄-2,7-[CH=N(2,6- ⁱPr ₂C ₆H ₃)](PMe ₃)} [TMS-FI ²-Ni(PMe ₃)]. The Fl ²-Ni ₂ catalysts exhibit significant increases in ethylene homopolymerization activity versus the monometallic analogues, as well as increased branching and methyl branch selectivity, even in the absence of a Ni(cod) ₂ cocatalyst. Increasing ethylene concentrations significantly suppress branching and alter branch morphology. FI ²-Ni ₂-mediated copolymerizations with ethylene + polar-functionalized norbornenes exhibit a 4-fold increase in comonomer incorporation versus Fl-Ni, yielding copolymers with up to 10% norbornene copolymer incorporation. FI ²-Ni ₂-catalyzed copolymerizations with ethylene + methylacrylate or methyl methacrylate incorporate up to 11% acrylate comonomer, while the corresponding mononuclear Fl-Ni catalysts incorporate negligible amounts. Furthermore, the FI ²-Ni ₂-mediated polymerizations exhibit appreciable polar solvent tolerance, turning over in the presence of ethyl ether, acetone, and even water. The mechanism by which the present cooperative effects take place is investigated, as is the nature of the copolymer microstructures produced.

Original language	English (US)
Pages (from-to)	5902-5919
Number of pages	18
Journal	Journal of the American Chemical Society
Volume	131
Issue number	16
DOIs	https://doi.org/10.1021/ja900257k
State	Published - Apr 29 2009

ASJC Scopus subject areas

Catalysis
General Chemistry
Biochemistry
Colloid and Surface Chemistry

Access to Document

10.1021/ja900257k

Cite this

@article{3e53d82281764eaeb4dd3f7c25c2f2cd,

title = "Bimetallic effects for enhanced polar comonomer enchainment selectivity in catalytic ethylene polymerization",

abstract = "The synthesis and characterization of the bimetallic 2,7-di-[(2,6- diisopropylphenyl)imino]-1,8- naphthalenediolato group 10 metal polymerization catalysts {[Ni(CH 3)] 2[1,8-(O) 2C 10H 4-2,7-[CH=N(2,6- Pr 2C 6H 3)](PMe 3) 2} and {[Ni(1-naphthyl)] 2[1,8-(O) 2C 10H 4-2,7-[CH=N(2,6-Pr 2C 6H 3)](PPh 3) 2} [FI 2-Ni 2(PR 3) 2] are presented, along with the synthesis and characterization of the mononuclear analogues {Ni(CH 3)[3- tBu- 2-(0)C 6H 3CH=N(2,6- iPr 2C 6H 3)](PMe) 3}and{Ni(1-naphthyl)[3- tBu-2-(0)C 6H 3CH=N(2,6- iPr 2C 6H 3)](PPh) 3}[FI- Ni (PR 3)]. Monometallic Ni catalysts were also prepared by functionalizing one ligation center of the bimetallic ligand with a trimethylsilyl group (TMS), yielding {Ni(CH 3)[1,8-(O)(TMSO)C 10H 4-2,7-[CH=N(2,6- iPr 2C 6H 3)](PMe 3)} [TMS-FI 2-Ni(PMe 3)]. The Fl 2-Ni 2 catalysts exhibit significant increases in ethylene homopolymerization activity versus the monometallic analogues, as well as increased branching and methyl branch selectivity, even in the absence of a Ni(cod) 2 cocatalyst. Increasing ethylene concentrations significantly suppress branching and alter branch morphology. FI 2-Ni 2-mediated copolymerizations with ethylene + polar-functionalized norbornenes exhibit a 4-fold increase in comonomer incorporation versus Fl-Ni, yielding copolymers with up to 10% norbornene copolymer incorporation. FI 2-Ni 2-catalyzed copolymerizations with ethylene + methylacrylate or methyl methacrylate incorporate up to 11% acrylate comonomer, while the corresponding mononuclear Fl-Ni catalysts incorporate negligible amounts. Furthermore, the FI 2-Ni 2-mediated polymerizations exhibit appreciable polar solvent tolerance, turning over in the presence of ethyl ether, acetone, and even water. The mechanism by which the present cooperative effects take place is investigated, as is the nature of the copolymer microstructures produced.",

author = "Rodriguez, {Brandon A.} and Massimiliano Delferro and Marks, {Tobin J.}",

year = "2009",

month = apr,

day = "29",

doi = "10.1021/ja900257k",

language = "English (US)",

volume = "131",

pages = "5902--5919",

journal = "Journal of the American Chemical Society",

issn = "0002-7863",

publisher = "American Chemical Society",

number = "16",

}

TY - JOUR

T1 - Bimetallic effects for enhanced polar comonomer enchainment selectivity in catalytic ethylene polymerization

AU - Rodriguez, Brandon A.

AU - Delferro, Massimiliano

AU - Marks, Tobin J.

PY - 2009/4/29

Y1 - 2009/4/29

N2 - The synthesis and characterization of the bimetallic 2,7-di-[(2,6- diisopropylphenyl)imino]-1,8- naphthalenediolato group 10 metal polymerization catalysts {[Ni(CH 3)] 2[1,8-(O) 2C 10H 4-2,7-[CH=N(2,6- Pr 2C 6H 3)](PMe 3) 2} and {[Ni(1-naphthyl)] 2[1,8-(O) 2C 10H 4-2,7-[CH=N(2,6-Pr 2C 6H 3)](PPh 3) 2} [FI 2-Ni 2(PR 3) 2] are presented, along with the synthesis and characterization of the mononuclear analogues {Ni(CH 3)[3- tBu- 2-(0)C 6H 3CH=N(2,6- iPr 2C 6H 3)](PMe) 3}and{Ni(1-naphthyl)[3- tBu-2-(0)C 6H 3CH=N(2,6- iPr 2C 6H 3)](PPh) 3}[FI- Ni (PR 3)]. Monometallic Ni catalysts were also prepared by functionalizing one ligation center of the bimetallic ligand with a trimethylsilyl group (TMS), yielding {Ni(CH 3)[1,8-(O)(TMSO)C 10H 4-2,7-[CH=N(2,6- iPr 2C 6H 3)](PMe 3)} [TMS-FI 2-Ni(PMe 3)]. The Fl 2-Ni 2 catalysts exhibit significant increases in ethylene homopolymerization activity versus the monometallic analogues, as well as increased branching and methyl branch selectivity, even in the absence of a Ni(cod) 2 cocatalyst. Increasing ethylene concentrations significantly suppress branching and alter branch morphology. FI 2-Ni 2-mediated copolymerizations with ethylene + polar-functionalized norbornenes exhibit a 4-fold increase in comonomer incorporation versus Fl-Ni, yielding copolymers with up to 10% norbornene copolymer incorporation. FI 2-Ni 2-catalyzed copolymerizations with ethylene + methylacrylate or methyl methacrylate incorporate up to 11% acrylate comonomer, while the corresponding mononuclear Fl-Ni catalysts incorporate negligible amounts. Furthermore, the FI 2-Ni 2-mediated polymerizations exhibit appreciable polar solvent tolerance, turning over in the presence of ethyl ether, acetone, and even water. The mechanism by which the present cooperative effects take place is investigated, as is the nature of the copolymer microstructures produced.

AB - The synthesis and characterization of the bimetallic 2,7-di-[(2,6- diisopropylphenyl)imino]-1,8- naphthalenediolato group 10 metal polymerization catalysts {[Ni(CH 3)] 2[1,8-(O) 2C 10H 4-2,7-[CH=N(2,6- Pr 2C 6H 3)](PMe 3) 2} and {[Ni(1-naphthyl)] 2[1,8-(O) 2C 10H 4-2,7-[CH=N(2,6-Pr 2C 6H 3)](PPh 3) 2} [FI 2-Ni 2(PR 3) 2] are presented, along with the synthesis and characterization of the mononuclear analogues {Ni(CH 3)[3- tBu- 2-(0)C 6H 3CH=N(2,6- iPr 2C 6H 3)](PMe) 3}and{Ni(1-naphthyl)[3- tBu-2-(0)C 6H 3CH=N(2,6- iPr 2C 6H 3)](PPh) 3}[FI- Ni (PR 3)]. Monometallic Ni catalysts were also prepared by functionalizing one ligation center of the bimetallic ligand with a trimethylsilyl group (TMS), yielding {Ni(CH 3)[1,8-(O)(TMSO)C 10H 4-2,7-[CH=N(2,6- iPr 2C 6H 3)](PMe 3)} [TMS-FI 2-Ni(PMe 3)]. The Fl 2-Ni 2 catalysts exhibit significant increases in ethylene homopolymerization activity versus the monometallic analogues, as well as increased branching and methyl branch selectivity, even in the absence of a Ni(cod) 2 cocatalyst. Increasing ethylene concentrations significantly suppress branching and alter branch morphology. FI 2-Ni 2-mediated copolymerizations with ethylene + polar-functionalized norbornenes exhibit a 4-fold increase in comonomer incorporation versus Fl-Ni, yielding copolymers with up to 10% norbornene copolymer incorporation. FI 2-Ni 2-catalyzed copolymerizations with ethylene + methylacrylate or methyl methacrylate incorporate up to 11% acrylate comonomer, while the corresponding mononuclear Fl-Ni catalysts incorporate negligible amounts. Furthermore, the FI 2-Ni 2-mediated polymerizations exhibit appreciable polar solvent tolerance, turning over in the presence of ethyl ether, acetone, and even water. The mechanism by which the present cooperative effects take place is investigated, as is the nature of the copolymer microstructures produced.

UR - http://www.scopus.com/inward/record.url?scp=69949120884&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=69949120884&partnerID=8YFLogxK

U2 - 10.1021/ja900257k

DO - 10.1021/ja900257k

M3 - Article

C2 - 19351155

AN - SCOPUS:69949120884

SN - 0002-7863

VL - 131

SP - 5902

EP - 5919

JO - Journal of the American Chemical Society

JF - Journal of the American Chemical Society

IS - 16

ER -

Bimetallic effects for enhanced polar comonomer enchainment selectivity in catalytic ethylene polymerization

Abstract

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

CCDC 740303: Experimental Crystal Structure Determination

Cite this

Bimetallic effects for enhanced polar comonomer enchainment selectivity in catalytic ethylene polymerization

Abstract

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Datasets

CCDC 740303: Experimental Crystal Structure Determination

Cite this