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Geminal Aminocyanation Enabled by Ylide Mediated Rearrangement
Zichun Yan1, Meirong Huang2, Chuang Wang1
1Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China.
Organic Letters
|November 25, 2024
Summary
This study introduces a new method for cyanation reactions using oxycyanopyridinium ylides, forming both C-N and C-C bonds. Enantioselective versions were achieved using chiral rhodium catalysts.
Area of Science:
- Organic Chemistry
- Catalysis
- Computational Chemistry
Background:
- Oxycyanopyridinium ylides are reactive intermediates.
- Cyanation reactions are crucial in organic synthesis.
- Developing new methods for C-N and C-C bond formation is important.
Purpose of the Study:
- To investigate the generation and reactivity of oxycyanopyridinium ylides.
- To understand the mechanism of concomitant C-N and C-C bond formation.
- To develop enantioselective cyanation reactions.
Main Methods:
- In situ generation of oxycyanopyridinium ylides from oxy-cyanopyridines and rhodium carbene.
- Experimental studies to characterize the reaction products.
- Density functional theory (DFT) calculations to elucidate the reaction mechanism.
- Use of chiral dirhodium complexes for enantioselective catalysis.
Main Results:
- Concomitant formation of C-N and C-C bonds was achieved.
- A mechanism involving sequential metal-bound ylide formation, a rhodium-associated five-membered transition state, and 1,4-cyano group relocation was proposed.
- Enantioselective cyanation reactions were successfully realized using chiral dirhodium catalysts.
Conclusions:
- The developed method offers a complementary approach for cyanation reactions.
- The mechanistic insights provide a deeper understanding of ylide chemistry.
- The enantioselective variant expands the synthetic utility of this transformation.
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