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Fabrication and Characterization of Thickness Mode Piezoelectric Devices for Atomization and Acoustofluidics
Published on: August 5, 2020
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Electro-Mechanochemical Atom Transfer Radical Cyclizations using Piezoelectric BaTiO3.
Christian Schumacher1, José G Hernández1, Carsten Bolm1
1Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany.
Angewandte Chemie (International Ed. in English)
|June 10, 2020
Summary
Mechanical ball milling of barium titanate (BaTiO3) generates electrical polarization, reducing copper(II) to the active copper(I) species. This enables efficient copper-catalyzed mechanochemical solvent-free atom transfer radical cyclizations (ATRC).
Area of Science:
- Organic Chemistry
- Materials Science
- Catalysis
Background:
- Copper(I) species are crucial for copper-catalyzed atom transfer radical cyclizations (ATRC).
- Traditionally, active Cu(I) requires high catalyst loadings or reducing agents.
- Mechanochemical approaches offer solvent-free reaction conditions.
Purpose of the Study:
- To investigate the use of piezoelectric materials for generating active Cu(I) species.
- To develop a novel method for copper-catalyzed mechanochemical ATRC reactions.
- To harness mechanical energy for catalyst activation.
Main Methods:
- Utilizing barium titanate (BaTiO3) as a piezoelectric material.
- Employing mechanical ball milling to induce electrical polarization.
- Performing solvent-free atom transfer radical cyclizations (ATRC).
Main Results:
- Piezoelectric effect of BaTiO3 successfully reduced Cu(II) precatalyst to active Cu(I) species.
- Mechanochemical activation via ball milling enabled catalyst regeneration.
- Efficient copper-catalyzed solvent-free ATRC reactions were achieved.
Conclusions:
- Barium titanate's piezoelectric properties can activate copper catalysts under mechanochemical conditions.
- This method provides a sustainable route for copper-catalyzed ATRC reactions.
- Mechanical energy can be converted to drive catalytic cycles.
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