Elucidating the Key Role of Phosphine-Sulfonate Ligands in Palladium-Catalyzed Ethylene Polymerization: Effect of Ligand Structure on the Molecular Weight and Linearity of Polyethylene

Nakano, Ryo1; Chung, Lung Wa2; Watanabe, Yumiko3; Okuno, Yoshishige3; Okumura, Yoshikuni4; Ito, Shingo1; Morokuma, Keiji5; Nozaki, Kyoko1

2016-09

10.1021/acscatal.6b00911

ACS Catalysis   影响因子和分区

2155-5435

The mechanism of linear polyethylene formation catalyzed by palladium/phosphine sulfonate and the effect of the ligand structure on the catalytic performance, such as linearity and molecular weight of the polyethylene, were reinvestigated theoretically and experimentally. We used dispersion-corrected density functional theory (DFT-D3) to study the entire mechanism of polyethylene formation from (R2PC6H4SO3)PdMe(2,6-lutidine) (R = Me, t-Bu) and elucidated the key steps that determine the molecular weight and linearity of the polyethylene. The alkylpalladium ethylene complex is the key intermediate for both linear propagation and fi-hydride elimination from the growing polymer chain. On the basis of the key species, the effects of substituents on the phosphorus atom (R = t-Bu, i-Pr, Cy, Men, Ph, 2-MeOC6H4, biAr) were further investigated theoretically to explain the experimental results in a comprehensive manner. Thus, the experimental trend of molecular weights of polyethylene could be correlated to the AA G* value between (i) the transition state of linear propagation and (ii) the transition state of the path for ethylene dissociation leading to fi-hydride elimination. Moreover, the experimental behavior of the catalysts under varied ethylene pressure was well explained by our computation on the small set of key species elucidated from the entire mechanism. In our additional experimental investigations, [o-Ani(2)PC(6)H(4)SO(3)]PdH[P(t-Bu)(3)] catalyzed a hydrogen/ deuterium exchange reaction between ethylene and Me0D. The deuterium incorporation from Me0D into the main chain of polyethylene, therefore, can be explained by the incorporation of deuterated ethylene formed by a small amount of Pd H species. These insights into the palladium/phosphine sulfonate system provide a comprehensive understanding of how the phosphine sulfonate ligands function to produce linear polyethylene.

phosphine sulfonate palladium catalysts ethylene polymerization linearity molecular weight suppression of beta-hydride elimination

SCI ; EI

英语

其他

Japan Science and Technology Agency[] ; Japan Society for the Promotion of Science[] ; Japan Society for the Promotion of Science[] ; Core Research for Evolutional Science and Technology[] ; National Institutes of Natural Sciences[]

Chemistry

Chemistry, Physical

WOS:000382714000052

AMER CHEMICAL SOC

20163602781204

Catalysis ; Catalysts ; Computation theory ; Density functional theory ; Deuterium ; Ethylene ; Hydrides ; Molecular weight ; Palladium ; Palladium compounds ; Phosphorus compounds ; Polyethylenes ; Polymerization

Precious Metals:547.1 ; Computer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming Theory:721.1 ; Physical Chemistry:801.4 ; Chemical Reactions:802.2 ; Chemical Agents and Basic Industrial Chemicals:803 ; Chemical Products Generally:804 ; Organic Polymers:815.1.1 ; Polymerization:815.2 ; Atomic and Molecular Physics:931.3

Web of Science

1.Univ Tokyo, Grad Sch Engn, Dept Chem & Biotechnol, Bunkyo Ku, 7-3-1 Hongo, Tokyo 1138656, Japan
2.South Univ Sci & Technol China, Dept Chem, Shenzhen 518055, Peoples R China
3.Computat Sci & Technol Informat Ctr, Showa Denko KK, Midori Ku, 1-1-1 Ohnodai, Chiba, Chiba 2670056, Japan
4.Inst Adv & Core Technol, Showa Denko KK, 2 Nakanosu, Oita, Oita 8701809, Japan
5.Kyoto Univ, Fukui Inst Fundamental Chem, Sakyo Ku, 34-4 Takano Nishihiraki Cho, Kyoto 6068103, Japan

Nakano, Ryo,Chung, Lung Wa,Watanabe, Yumiko,et al. Elucidating the Key Role of Phosphine-Sulfonate Ligands in Palladium-Catalyzed Ethylene Polymerization: Effect of Ligand Structure on the Molecular Weight and Linearity of Polyethylene[J]. ACS Catalysis,2016,6(9):6101-6113.

Nakano, Ryo.,Chung, Lung Wa.,Watanabe, Yumiko.,Okuno, Yoshishige.,Okumura, Yoshikuni.,...&Nozaki, Kyoko.(2016).Elucidating the Key Role of Phosphine-Sulfonate Ligands in Palladium-Catalyzed Ethylene Polymerization: Effect of Ligand Structure on the Molecular Weight and Linearity of Polyethylene.ACS Catalysis,6(9),6101-6113.

Nakano, Ryo,et al."Elucidating the Key Role of Phosphine-Sulfonate Ligands in Palladium-Catalyzed Ethylene Polymerization: Effect of Ligand Structure on the Molecular Weight and Linearity of Polyethylene".ACS Catalysis 6.9(2016):6101-6113.