Supported gold nanoparticle-catalyzed hydration of alkynes under basic conditions
Shengzong Liang1, Jacek Jasinski, Gerald B Hammond
1Department of Chemistry and ‡Institute for Advanced Materials and Renewable Energy, University of Louisville , Louisville, Kentucky 40292, United States.
Organic Letters
|December 18, 2014
Summary
A novel titanium dioxide-supported gold nanoparticle catalyst enables alkyne hydration under mild, weakly basic conditions. This recyclable catalyst is compatible with sensitive functional groups and effective in flow reactors.
Area of Science:
- Catalysis
- Materials Science
- Organic Chemistry
Background:
- Gold catalysis is crucial for organic synthesis.
- Traditional gold catalysts often require harsh conditions or are incompatible with sensitive functional groups.
- Developing robust and versatile gold catalysts remains an active research area.
Purpose of the Study:
- To develop a novel heterogeneous gold catalyst for alkyne hydration.
- To investigate the compatibility of the catalyst with acid-sensitive and coordinating functional groups.
- To assess the recyclability and performance of the catalyst in flow chemistry.
Main Methods:
- Synthesis of nanosize gold particles supported on titanium dioxide (TiO2).
- Catalytic hydration of alkynes using the TiO2-supported gold catalyst with morpholine as a co-catalyst.
- Evaluation of catalyst compatibility with various functional groups.
- Testing catalyst recyclability and performance in continuous flow reactors.
Main Results:
- The TiO2-supported gold nanoparticle catalyst efficiently catalyzes alkyne hydration.
- The catalyst operates under weakly basic conditions, showing compatibility with silyl ethers, ketals, and pyridine.
- The heterogeneous gold catalyst can be easily recovered by filtration and reused.
- The system demonstrates good performance in flow reactor setups.
Conclusions:
- TiO2-supported gold nanoparticles offer a versatile and recyclable catalytic system for alkyne hydration.
- This approach overcomes limitations of homogeneous cationic gold catalysts, enabling reactions with sensitive substrates.
- The catalyst's suitability for flow chemistry opens avenues for efficient and scalable synthetic processes.
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