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Synthesis of a Thiol Building Block for the Crystallization of a Semiconducting Gyroidal Metal-sulfur Framework
Published on: April 9, 2018
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(Thio)urea-Based Covalent Organic Framework as a Hydrogen-Bond-Donating Catalyst.
Jiyun Hu1, Federica Zanca2, Patricia Lambe1
1Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701, United States.
ACS Applied Materials & Interfaces
|June 9, 2020
Summary
New two-dimensional covalent organic frameworks (COFs) containing urea and thiourea were synthesized rapidly at ambient conditions. These COF catalysts exhibit superior efficiency and recyclability for key organic reactions compared to molecular catalysts.
Area of Science:
- Materials Science
- Organic Chemistry
- Catalysis
Background:
- Covalent organic frameworks (COFs) are crystalline porous polymers with tunable structures.
- Organocatalysis offers a metal-free alternative for various chemical transformations.
- Developing efficient and recyclable catalysts is crucial for sustainable chemistry.
Purpose of the Study:
- To synthesize novel two-dimensional urea- and thiourea-containing COFs.
- To evaluate the catalytic performance of these COFs as hydrogen-bond-donating organocatalysts.
- To compare their efficiency and recyclability against molecular counterparts.
Main Methods:
- Ambient condition synthesis of COFs within 1 hour.
- Utilizing site-isolated urea and thiourea functionalities within the COF structure.
- Testing catalytic activity in epoxide ring-opening, aldehyde acetalization, and Friedel-Crafts reactions.
Main Results:
- Successful large-scale synthesis of 2D urea/thiourea COFs under mild conditions.
- Enhanced catalytic efficiency of COF catalysts compared to molecular analogues.
- Demonstrated excellent recyclability of the COF catalysts over multiple reaction cycles.
Conclusions:
- Site-isolated urea and thiourea in COFs act as highly effective organocatalysts.
- These COFs represent a promising class of recyclable catalysts for organic synthesis.
- The developed synthetic method allows for rapid, large-scale production of COF catalysts.
Keywords:
catalyst quenchingcovalent organic frameworkshydrogen-bond-donating catalystsite isolationthioureaMore Related Videos
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