Predesign of Covalent-Organic Frameworks for Efficient Photocatalytic Dehydrogenative Cross-Coupling Reaction

Area of Science:

• Materials Science
• Organic Chemistry
• Catalysis

Background:

• Dehydrogenative cross-coupling is key for synthesizing 4-quinazolinone drugs.
• Traditional methods require harsh conditions (high temperature, long reaction times) and yield low product output.

Purpose of the Study:

• To design and construct novel heterogeneous tandem catalysts for efficient 4-quinazolinone synthesis.
• To overcome the limitations of existing methods by enabling reactions under mild, light-driven conditions.

Main Methods:

• Synthesis of two photosensitive covalent-organic frameworks (COFs): TAPP-An and TAPP-Cu-An.
• Utilizing these COFs as heterogeneous catalysts in dehydrogenative cross-coupling reactions.
• Employing a combination of experimental studies and theoretical calculations to understand catalytic mechanisms.

Main Results:

• TAPP-An and TAPP-Cu-An demonstrated efficient catalysis under mild conditions (room temperature, light).
• TAPP-Cu-An significantly outperformed existing catalysts, achieving >99% conversion and >99% selectivity in one-step synthesis.
• Gram-scale production of 4-quinazolinones was achieved with high efficiency.

Conclusions:

• The developed COFs, particularly TAPP-Cu-An, represent a breakthrough in heterogeneous catalysis for 4-quinazolinone synthesis.
• Excellent photogenerated charge separation, transport, and synergistic An-Cu catalysis are crucial for TAPP-Cu-An's high performance.
• This approach offers a sustainable and highly efficient route for pharmaceutical synthesis.