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Updated: Jan 16, 2026

Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry

Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry

Published on: October 18, 2019

SABRE Ir-IMes Catalysis for the Masses.

Izabelle Smith¹, Noah Terkildsen^1,2, Zachary Bender^1,2

¹Department of Chemistry Biology and Health Sciences, South Dakota School of Mines & Technology, Rapid City, SD 57701, USA.

Molecules (Basel, Switzerland)

|September 27, 2025

Summary

A new, simplified synthesis of the Ir-IMes catalyst enables broader access to Signal Amplification By Reversible Exchange (SABRE) hyperpolarization. This cost-effective method avoids specialized equipment, making advanced NMR techniques more accessible for researchers.

Keywords:

NMR spectroscopy SABRE hyperpolarization iridium parahydrogen

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Last Updated: Jan 16, 2026

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Area of Science:

Chemistry
Analytical Chemistry
Physical Chemistry

Background:

Signal Amplification By Reversible Exchange (SABRE) enhances Nuclear Magnetic Resonance (NMR) signals using parahydrogen.
The Ir-IMes catalyst is crucial for SABRE but traditionally requires complex synthesis.
Limited accessibility of the catalyst hinders SABRE methodology dissemination.

Purpose of the Study:

To develop a simplified, cost-effective, and reproducible synthesis for the Ir-IMes SABRE catalyst.
To make SABRE hyperpolarization techniques more accessible to a wider scientific community.
To validate the synthesis on a larger scale compared to previous methods.

Main Methods:

A robust synthetic procedure for the Ir-IMes catalyst was developed.
The synthesis bypasses the need for specialized inert atmosphere equipment (glove box, Schlenk line).
The procedure was scaled up to several grams, significantly larger than prior methods.

Main Results:

The synthesized [Ir(IMes)(COD)Cl] catalyst was successfully activated in situ.
Hyperpolarization experiments demonstrated signal enhancements comparable to or exceeding those from catalysts made with specialized equipment.
The simplified synthesis proved effective and reproducible on a multi-gram scale.

Conclusions:

A simplified, inexpensive, and scalable synthesis of the Ir-IMes SABRE catalyst is presented.
This method lowers the barrier for researchers to utilize SABRE hyperpolarization.
The developed procedure facilitates broader adoption and application of SABRE NMR techniques.