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Updated: Apr 16, 2026

Heterogeneous Removal of Water-Soluble Ruthenium Olefin Metathesis Catalyst from Aqueous Media Via Host-Guest Interaction
Published on: August 23, 2018
A simple iridicycle catalyst for efficient transfer hydrogenation of N-heterocycles in water
Dinesh Talwar1, Ho Yin Li, Emma Durham
1Department of Chemistry, University of Liverpool, Liverpool, L69 7ZD (UK) http://pcwww.liv.ac.uk/∼jxiao.
Abstract:
A cyclometalated iridium complex is shown to catalyse the transfer hydrogenation of various nitrogen heterocycles, including but not limited to quinolines, isoquinolines, indoles and pyridinium salts, in an aqueous solution of HCO2H/HCO2Na under mild conditions. The catalyst shows excellent functional-group compatibility and high turnover number (up to 7500), with catalyst loadings as low as 0.01 mol % being feasible. Mechanistic investigation of the quinoline reduction suggests that the transfer hydrogenation proceeds via both 1,2- and 1,4-addition pathways, with the catalytic turnover being limited by the step of hydride transfer.
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