Exploring Hydrogen Sources in Catalytic Transfer Hydrogenation: A Review of Unsaturated Compound Reduction
Batoul Taleb1,2, Rabih Jahjah1, David Cornu3
1Platform for Research and Analysis in Environmental Sciences (PRASE), Doctoral School of Science and Technology, Lebanese University, Beirut P.O. Box 6573/14, Lebanon.
Molecules (Basel, Switzerland)
|November 25, 2023
Summary
Catalytic transfer hydrogenation offers a safer, cost-effective alternative to direct hydrogenation. This review explores various hydrogen donors and future trends for enhanced selectivity and efficiency in chemical processes.
Area of Science:
- Green Chemistry
- Organic Synthesis
- Catalysis
Background:
- Catalytic transfer hydrogenation (CTH) is a key process for transferring hydrogen between molecules using a catalyst.
- CTH presents advantages over direct hydrogenation, including improved safety, economical hydrogen sources, and byproduct recyclability.
Purpose of the Study:
- To review the significance and applications of catalytic transfer hydrogenation.
- To explore diverse hydrogen donor molecules and their impact on catalytic systems.
- To outline future trends and innovations in CTH.
Main Methods:
- Review of existing literature on catalytic transfer hydrogenation.
- Analysis of various hydrogen donor molecules (alcohols, formic acid, glycerol, etc.).
- Discussion of catalyst compatibility, reaction conditions, and mechanistic insights.
Main Results:
- Alcohols and formic acid are effective hydrogen donors; formic acid enables irreversible hydrogenation.
- Unconventional donors like glycerol offer green solvent properties and efficient reductions.
- Compatibility studies highlight donor-catalyst-substrate interactions.
Conclusions:
- CTH is a versatile and advantageous hydrogenation method.
- Future directions include biomass-derived donors, MOFs for hydrogen storage, and eco-friendly solvents.
- Continued research will enhance CTH selectivity, efficiency, and industrial applicability.
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