Citation: Xiao-Lin Chen, Jie Gao, Heng Liao, Hai-Yang Gao, Qing Wu. Synthesis, Characterization, and Catalytic Ethylene Oligomerization of Pyridine-imine Palladium Complexes[J]. Chinese Journal of Polymer Science, ;2018, 36(2): 176-184. doi: 10.1007/s10118-018-2052-8 shu

Synthesis, Characterization, and Catalytic Ethylene Oligomerization of Pyridine-imine Palladium Complexes

School of Materials Science and Engineering, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, Guangdong Laboratory of High-performance Polymer Composites, Sun Yat-sen University, Guangzhou 510275, China

Corresponding author: Hai-Yang Gao, gaohy@mail.sysu.edu.cn
Received Date: 28 August 2017
Accepted Date: 28 September 2017
Available Online: 21 November 2017

Two neutral five-membered pyridine-imine palladium complexes with the bulky dibenzhydryl (CH(Ph)₂) substituted aniline were synthesized and fully characterized by nuclear magnetic resonance (NMR) and X-ray crystal diffraction. Well-defined cationic palladium complexes were further obtained by treatment of chloromethylpalladium complexes with sodium tetrakis(3, 5-bis(trifluoromethyl)phenyl)borate (NaBArF) in CH₃CN. Cationic palladium complexes were capable of catalyzing ethylene oligomerization without any cocatalysts. The influences of catalyst structure, reaction temperature, and ethylene pressure on ethylene oligomerization were studied in detail. The introduction of bulky benzhydryl (CH(Ph)₂) on the ortho position of the aniline moiety enhanced catalytic activity, thermal stability of the catalyst, and molecular weight of the obtained products. Highly branched oligomers with molecular weights of 600-800 g/mol and narrow polydispersities (1.03-1.12) were produced.
- Palladium,
- Ethylene,
- Oligomerization,
- Branching
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