Transition Metal Catalysis
With our continuing effort to study metal-ligand multiple bonds and their applications in transition metal catalysis for practical organic transformations, various metal catalysts have been developed for oxygen atom and carbene or nitrene group transfer/insertion reactions. Through judicious choice of ligands and metal ions, we are able to synthesize and isolate diverse classes of metal-oxygen, -nitrogen and -carbon multiply bonded complexes including highly reactive ones for understanding the mechanisms of metal-catalyzed atom and group transfer to organic substrates at the molecular level via spectroscopic measurements and/or by DFT calculations. Useful structural information has been obtained for the rational design of more robust metal catalysts with higher selectivity. |
1. Iron Catalysis
In collaboration with Shanghai Institute of Organic Chemistry (SIOC), we have been working on the development of practical iron-catalyzed organic transformation reactions. Development of iron catalysts, compared with other transition metal catalysts, is of most significance because of (1) the high earth abundance of iron, which limits preparation cost of the iron catalysts to an affordable level; (2) the excellent biocompatibility of iron complexes, which renders iron catalysts the best for the synthesis of bioactive molecules; (3) the robust catalytic activity of iron complexes towards organic transformations with excellent selectivity. We envision that the development of iron catalysis is the increasing trend in the academia, and this would also be the future trend to the chemical industry as a plausible solution to the pollution problem faced in the current industrial practices. The major challenge of this study would be the synthesis and characterization of the high-valent iron-oxo and/or iron-nitrido species, which are highly reactive for selective bond-forming reactions. |
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2. Atom and/or Group Transfer Reactions and C–H Functionalization
Direct and selective C–H bond functionalization is appealing for organic synthesis because of the ubiquity of C–H bonds in organic molecules, and this strategy provides promising potential in streamlining the synthetic routes of useful chemicals, including molecules with biological or pharmaceutical activities, new materials and reaction intermediates towards these purposes. This strategy also coincides with the principles of Green Chemistry by elevating atom and energy economy with minimum production of wastes, which bring the development of academic research and synthetic chemical industry towards a sustainable future. With our continuing effort on metal-ligand multiple bonds, we focus on the carbene, nitrene and oxygen transfer/insertion reactions. Our catalytic systems allow selective carbene and nitrene transfer reactions with desired product yields up to 99%, which advances the development of atom and group transfer reactions. |
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3. Application on Synthesis of Natural Products
We have also applied these atom and group transfer reactions to the formal synthesis of natural products and bioactive molecules, showing the potential of these reactions in practical organic syntheses.
We have also applied these atom and group transfer reactions to the formal synthesis of natural products and bioactive molecules, showing the potential of these reactions in practical organic syntheses.
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