Highly Active and Thermally Robust Nickel Enolate Catalysts for the Synthesis of Ethylene‐Acrylate Copolymers
Abstract
The insertion copolymerization of polar olefins and ethylene remains a significant challenge in part due to catalysts′ low activity and poor thermal stability. Herein we demonstrate a strategy toward addressing these obstacles through ligand design. Neutral nickel phosphine enolate catalysts with large phosphine substituents reaching the axial positions of Ni achieve activity of up to 7.7×10³ kg mol⁻¹ h⁻¹ (efficiency >35×10³ g copolymer/g Ni) at 110 °C, notable for ethylene/acrylate copolymerization. NMR analysis of resulting copolymers reveals highly linear microstructures with main-chain ester functionality. Structure-performance studies indicate a strong correlation between axial steric hindrance and catalyst performance.
Additional Information
© 2022 Wiley-VCH GmbH. Version of Record online: 18 July 2022. Accepted manuscript online: 20 June 2022. Manuscript received: 06 May 2022. We are grateful to Dow for funding (T.A.) and to the Caltech SURF program for a Ronan Armaan Mack fellowship (A.H.). We thank Jerzy Klosin, Alex Nett for insightful discussions. We thank Heidi Clements for GPC and tBA incorporation analysis. We thank Michael Takase for assistance with X-ray crystallography and David VanderVelde for assistance with NMR spectroscopy. Support has been provided for the X-ray diffraction and NMR instrumentation via the Dow Next Generation Educator Fund. S.X. acknowledge Manar Shoshani for assistance in refinement of solid-state structures and Yu Chen for assistance in generating topographical steric maps. Data Availability Statement. The data that support the findings of this study are available in the Supporting Information of this article. The authors declare no conflict of interest.Attached Files
Accepted Version - Angew_Chem_Int_Ed_-_2022_-_Xiong_-_Highly_Active_and_Thermally_Robust_Nickel_Enolate_Catalysts_for_the_Synthesis_of.pdf
Files
| Name | Size | Download all |
|---|---|---|
|
md5:907413371e6c89c7897d0763f2b9d117
|
1.9 MB | Preview Download |
Additional details
- Eprint ID
- 115697
- Resolver ID
- CaltechAUTHORS:20220720-917478000
- Caltech Summer Undergraduate Research Fellowship (SURF)
- Dow Next Generation Educator Fund
- Created
-
2022-07-22Created from EPrint's datestamp field
- Updated
-
2022-07-22Created from EPrint's last_modified field