C-Alkylation by Phenalenyl-Based Molecule via a Borrowing Hydrogen Pathway
Ananya Banik1, Paramita Datta1, Swadhin K Mandal1
1Department of Chemical Sciences, Indian Institute of Science Education and Research-Kolkata, Mohanpur 741246, India.
Organic Letters
|February 17, 2023
Summary
This study introduces the first transition-metal-free catalytic C-alkylation using a borrowing hydrogen pathway. This method enables ketone α-alkylation, quinoline synthesis, and fluorene monoalkylation, with potential for drug discovery and large-scale synthesis.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- Transition-metal catalysis is prevalent in C-alkylation reactions.
- Developing metal-free alternatives is crucial for sustainable chemistry.
- Borrowing hydrogen pathways offer efficient synthetic routes.
Purpose of the Study:
- To develop a novel transition-metal-free catalytic C-alkylation method.
- To explore the application of this method in synthesizing valuable organic molecules.
- To investigate the underlying reaction mechanism.
Main Methods:
- Utilizing a borrowing hydrogen pathway for catalytic C-alkylation.
- Applying the methodology to α-alkylation of ketones.
- Synthesizing substituted quinolines and 9-monoalkylation of fluorene.
- Conducting preliminary mechanistic studies.
Main Results:
- Demonstrated the first transition-metal-free catalytic C-alkylation via borrowing hydrogen.
- Successfully achieved α-alkylation of ketones.
- Synthesized substituted quinolines and monoalkylated fluorene.
- Preliminary mechanistic investigation suggests a radical-mediated pathway.
Conclusions:
- The developed method offers a novel, metal-free approach to C-alkylation.
- The methodology is applicable to the synthesis of diverse, biologically relevant molecules.
- The reaction proceeds via a radical-mediated borrowing hydrogen pathway, opening new avenues in catalysis research.
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