Issue 2, 2020

Ligand–metal secondary interactions in phosphine–sulfonate palladium and nickel catalyzed ethylene (co)polymerization

Abstract

Ligand–metal secondary interactions are an efficient strategy to modulate transition-metal-catalyzed ethylene (co)polymerizations. In this contribution, some phosphine–sulfonate Pd and Ni catalysts, bearing sp2 hybrid N based aromatic carbazolyl and pyrrolyl units in their ligand framework, have been designed and synthesized. The N-heterocyclic unit can interact with the Pd or Ni center, thus inducing ligand–metal secondary interactions. Moreover, these secondary interactions could be modulated through the addition of a Lewis acid reagent. The Pd catalysts exhibit high activities in ethylene polymerization and copolymerization with a variety of polar comonomers (methyl acrylate, acrylic acid, 6-chloro-1-hexene, 10-undecenol and 10-undecenoic acid), resulting in high molecular weight (co)polymers. The Ni catalysts show low activities, affording low molecular weight (co)polymers. Both the Pd and Ni catalysts demonstrate enhanced thermal stability versus their analogues devoid of the ligand–metal interaction. The Lewis acidic additive B(C6F5)3 can efficiently increase activities and decrease polymer molecular weights. Specifically, a 670-fold increase of the chain transfer rate can be achieved in Pd catalyzed ethylene polymerization. The Lewis acid addition can also influence polymer microstructures in Ni catalyzed ethylene polymerization. The combination of ligand–metal secondary interactions with Lewis acid modulation makes this strategy highly versatile and potentially applicable to other catalytic processes.

Graphical abstract: Ligand–metal secondary interactions in phosphine–sulfonate palladium and nickel catalyzed ethylene (co)polymerization

Supplementary files

Article information

Article type
Paper
Submitted
20 Jun 2019
Accepted
06 Sep 2019
First published
09 Sep 2019

Polym. Chem., 2020,11, 411-416

Ligand–metal secondary interactions in phosphine–sulfonate palladium and nickel catalyzed ethylene (co)polymerization

C. Tan, M. Qasim, W. Pang and C. Chen, Polym. Chem., 2020, 11, 411 DOI: 10.1039/C9PY00904C

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements