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Title: Alkene Hydrosilylation on Oxide-Supported Pt-Ligand Single=Site Catalysts

Abstract

Heterogeneous single-site catalysts (SSCs), widely regarded as promising next-generation catalysts, blend the easy recovery of traditional heterogeneous catalysts with desired features of homogeneous catalysts: high fraction of active sites and uniform metal centers. We previously reported the synthesis of Pt-ligand SSCs through a novel metal-ligand self-assembly method on MgO, CeO 2, and Al 2O 3 supports (J. Catal. 2018, 365, 303-312). Here, we present their applications in the industrially-relevant alkene hydrosilylation reaction, with 95 % yield achieved under mild conditions. As expected, they exhibit better metal utilization efficiency than traditional heterogeneous Pt catalysts. The comparison with commercial catalysts (Karstedt and Speier) reveals several advantages of these SSCs: higher selectivity, less colloidal Pt formation, less alkene isomerization/hydrogenation, and better tolerance towards functional groups in substrates. Despite some leaching, our catalysts exhibit satisfactory recyclability and the single-site structure remains intact on oxide supports after reaction. Pt single-sites were proved to be the main active sites rather than colloidal Pt formed during the reaction. An induction period is observed in which Pt sites are activated by Cl detachment and replacement by reactant alkenes. The most active species likely involves temporary detachment of Pt from ligand or support. Catalytic performance of Pt SSCs ismore » sensitive to the ligand and support choices, enabling fine tuning of Pt sites. This work highlights the application of heterogeneous SSCs created by the novel metal-ligand self-assembly strategy in an industrially-relevant reaction. It also offers a potential catalyst for future industrial hydrosilylation applications with several improvements over current commercial catalysts.« less

Authors:
ORCiD logo [1]; ORCiD logo [1];  [2];  [3]; ORCiD logo [1]; ORCiD logo [1]
  1. Indiana Univ., Bloomington, IN (United States). Dept. of Chemistry
  2. Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
  3. Department of ChemistryIndiana University 800 E. Kirkwood Ave., Bloomington Indiana 47405 USA
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); National Science Foundation (NSF)
OSTI Identifier:
1563148
Alternate Identifier(s):
OSTI ID: 1515798
Grant/Contract Number:  
[AC02-06CH11357; SC0016367]
Resource Type:
Accepted Manuscript
Journal Name:
ChemCatChem
Additional Journal Information:
[ Journal Volume: 11; Journal Issue: 12]; Journal ID: ISSN 1867-3880
Publisher:
ChemPubSoc Europe
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; X-ray absorption spectroscopy; X-ray photoelectron spectroscopy; heterogeneous catalysis; hydrosilylation; platinum; single-site catalyst

Citation Formats

Chen, Linxiao, Ali, Iyad S., Sterbinsky, George E., Gamler, Jocelyn T. L., Skrabalak, Sara E., and Tait, Steven L. Alkene Hydrosilylation on Oxide-Supported Pt-Ligand Single=Site Catalysts. United States: N. p., 2019. Web. doi:10.1002/cctc.201900530.
Chen, Linxiao, Ali, Iyad S., Sterbinsky, George E., Gamler, Jocelyn T. L., Skrabalak, Sara E., & Tait, Steven L. Alkene Hydrosilylation on Oxide-Supported Pt-Ligand Single=Site Catalysts. United States. doi:10.1002/cctc.201900530.
Chen, Linxiao, Ali, Iyad S., Sterbinsky, George E., Gamler, Jocelyn T. L., Skrabalak, Sara E., and Tait, Steven L. Mon . "Alkene Hydrosilylation on Oxide-Supported Pt-Ligand Single=Site Catalysts". United States. doi:10.1002/cctc.201900530.
@article{osti_1563148,
title = {Alkene Hydrosilylation on Oxide-Supported Pt-Ligand Single=Site Catalysts},
author = {Chen, Linxiao and Ali, Iyad S. and Sterbinsky, George E. and Gamler, Jocelyn T. L. and Skrabalak, Sara E. and Tait, Steven L.},
abstractNote = {Heterogeneous single-site catalysts (SSCs), widely regarded as promising next-generation catalysts, blend the easy recovery of traditional heterogeneous catalysts with desired features of homogeneous catalysts: high fraction of active sites and uniform metal centers. We previously reported the synthesis of Pt-ligand SSCs through a novel metal-ligand self-assembly method on MgO, CeO2, and Al2O3 supports (J. Catal. 2018, 365, 303-312). Here, we present their applications in the industrially-relevant alkene hydrosilylation reaction, with 95 % yield achieved under mild conditions. As expected, they exhibit better metal utilization efficiency than traditional heterogeneous Pt catalysts. The comparison with commercial catalysts (Karstedt and Speier) reveals several advantages of these SSCs: higher selectivity, less colloidal Pt formation, less alkene isomerization/hydrogenation, and better tolerance towards functional groups in substrates. Despite some leaching, our catalysts exhibit satisfactory recyclability and the single-site structure remains intact on oxide supports after reaction. Pt single-sites were proved to be the main active sites rather than colloidal Pt formed during the reaction. An induction period is observed in which Pt sites are activated by Cl detachment and replacement by reactant alkenes. The most active species likely involves temporary detachment of Pt from ligand or support. Catalytic performance of Pt SSCs is sensitive to the ligand and support choices, enabling fine tuning of Pt sites. This work highlights the application of heterogeneous SSCs created by the novel metal-ligand self-assembly strategy in an industrially-relevant reaction. It also offers a potential catalyst for future industrial hydrosilylation applications with several improvements over current commercial catalysts.},
doi = {10.1002/cctc.201900530},
journal = {ChemCatChem},
number = [12],
volume = [11],
place = {United States},
year = {2019},
month = {5}
}

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