Pd(OAc)2-Catalyzed Approach to Phenanthridin-6(5H)-one Skeletons.
Ye Li1, Dong-Wei Wang1, Jian-Quan Liu1
1School of Chemistry and Materials Science, Jiangsu Key Laboratory of Green Synthesis for Functional Materials, Jiangsu Normal University, Xuzhou, Jiangsu 221116, China.
Organic Letters
|January 6, 2025
Summary
This study introduces a new palladium-catalyzed method for synthesizing 4-arylphenanthridinones. The adaptable route efficiently produces diverse phenanthridinones with excellent functional group tolerance.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- Phenanthridinones are important heterocyclic compounds with diverse biological activities.
- Efficient and modular synthetic routes are crucial for accessing diverse phenanthridinone derivatives.
Purpose of the Study:
- To develop a novel palladium-catalyzed synthesis of 4-arylphenanthridinones.
- To establish an adaptable and modular route for efficient phenanthridinone production.
- To explore alternative cross-coupling strategies for phenanthridinone synthesis.
Main Methods:
- Palladium(II) acetate (Pd(OAc)2) and 1,3-bis(diphenylphosphino)propane (Dppp) catalyzed coupling of 2-bromobenzamides and iodobenzene.
- Sequential Ullman cross-coupling, C-H activation, and oxidative coupling dehydrogenation.
- Alternative 1:1 cross-coupling using an intramolecular norbornene ligand for N-arylation and C-H activation.
Main Results:
- Successful synthesis of 4-arylphenanthridinones from readily available starting materials.
- Demonstrated adaptability and modularity of the synthetic route.
- Achieved high functional group compatibility.
- Developed an alternative method via N-arylation and C-H activation using a norbornene-based ligand.
Conclusions:
- The presented Pd(OAc)2/Dppp-catalyzed method provides an efficient and versatile approach to 4-arylphenanthridinones.
- The methodology is amenable to the synthesis of a wide range of valuable phenanthridinone derivatives.
- An alternative cross-coupling strategy offers further modularity in phenanthridinone synthesis.
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