Beyond the Active Site. Cp*ZrMe3/Sulfated Alumina-Catalyzed Olefin Polymerization Tacticity via Catalyst...Surface Ion-Pairing

被引：10

作者：

Zhang, Jialong ^{[1
,2
]}

Mason, Alexander H. ^{[1
,2
]}

Wang, Yang ^{[1
,2
]}

Motta, Alessandro ^{[3
,4
]}

Kobayashi, Takeshi ^{[5
]}

Pruski, Marek ^{[5
]}

Gao, Yanshan ^{[1
,2
]}

Marks, Tobin J. ^{[1
,2
]}

机构：

[1] Northwestern Univ, Dept Chem, 2145 Sheridan Rd, Evanston, IL 60208 USA

[2] Northwestern Univ, Inst Catalysis Energy Proc ICEP, 2145 Sheridan Rd, Evanston, IL 60208 USA

[3] Univ Roma La Sapienza, Dipartimento Sci Chim, Piazzale Aldo Moro 5, I-00185 Rome, Italy

[4] UdR Roma, INSTM, Piazzale Aldo Moro 5, I-00185 Rome, Italy

[5] Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA

来源：

CHEMCATCHEM | 2021年 / 13卷 / 11期

关键词：

Zirconocene; olefin polymerization; isotactic polypropylene; surface organometallics; solid-state NMR;

D O I：

10.1002/cctc.202100406

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Surface-bound organometallic molecules have recently enabled the development of single-site heterogeneous catalysts, advancing the atomic scale understanding and diversity of heterogeneous catalysis. Here we report that supporting Cp*ZrMe3 (Cat1) on acidic sulfated-alumina (AlS) affords the surface catalyst Cat1/AlS, which was characterized by multi-dimensional solid-state NMR spectroscopies, and is active in ethylene homo- and copolymerizations, as well as propylene and 1-hexene homopolymerizations. In contrast to propylene (or 1-hexene) polymerization by homogeneous Cp*ZrMe2+ B(C6F5)(4)(-) which yields atactic polyolefins, Cat1/AlS promotes remarkable isotacticity with mmmm >95 %. Complementary DFT analysis argues that the restrictive local Cat1/AlS C-1-symmetry favors activation and enchainment at the propylene re enantioface, promoting isotactic polymerization via a "back-skip-like" mechanism.

引用

页码：2564 / 2569

页数：6