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Updated: Oct 10, 2025
09:37
Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
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Rhodium-Iodide Complex on a Catalytically Active SiO2 Surface for One-Pot Hydrosilylation-CO2 Cycloaddition
Kei Usui1,2, Yuichi Manaka1,3, Wang-Jae Chun4
1Department of Chemical Science and Engineering, Tokyo Institute of Technology, Meguro City, 226-8502 Yokohama, Japan.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|December 8, 2021
Summary
A novel Rh-iodide catalyst on SiO2 enables efficient one-pot synthesis of silylcarbonates from epoxides, hydrosilanes, and CO2. This surface-confined complex shows high activity and stability, advancing catalytic applications.
Area of Science:
- Heterogeneous catalysis
- Organometallic chemistry
- Sustainable synthesis
Background:
- Development of efficient catalytic systems for CO2 utilization is crucial for sustainable chemistry.
- Immobilized metal complexes offer advantages in catalyst recovery and stability.
- Synthesis of silylcarbonates is an important transformation with applications in materials science.
Purpose of the Study:
- To synthesize and characterize a novel Rh-iodide complex immobilized on SiO2.
- To investigate the catalytic performance of the supported complex for the one-pot synthesis of silylcarbonates.
- To elucidate the mechanism and structural factors contributing to the catalyst's high activity.
Main Methods:
- Synthesis of a SiO2-supported Rh-iodide complex via surface reaction.
- Catalytic evaluation in a one-pot reaction involving epoxy olefins, hydrosilanes, and CO2.
- Characterization using X-ray absorption fine structure (XAFS) and X-ray photoelectron spectroscopy (XPS).
Main Results:
- The immobilized Rh-iodide complex effectively catalyzed the one-pot synthesis of silylcarbonates with high turnover numbers (TONs) up to 7600 for hydrosilylation.
- Spectroscopic analyses confirmed the presence of a Rh-I bond and an electron-rich Rh center, with evidence of cyclooctadiene (COD) ligand dissociation.
- The catalyst demonstrated superior performance compared to Rh complex alone, attributed to reduced steric hindrance and an electron-rich Rh state promoting Si-H activation.
Conclusions:
- A novel surface Rh-iodide complex immobilized on SiO2 was successfully synthesized and characterized.
- The catalyst enables an efficient one-pot synthesis of silylcarbonates, showcasing high catalytic activity and selectivity.
- The study provides mechanistic insights into the enhanced catalytic performance, highlighting the role of the co-immobilized iodide and Rh electronic state.
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