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Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes
Published on: September 8, 2013
Alkoxyamine-cyanoborane adducts: efficient cyanoborane transfer agents
José M Márquez1, Elisa Martínez-Castro, Serena Gabrielli
1Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, c/Profesor García González 1, E-41012, Seville, Spain.
Chemical Communications (Cambridge, England)
|April 13, 2011
Summary
Researchers synthesized novel zwitterionic alkoxyamino cyanoboranes and cyanoboronated N-alkoxyformamidines. These compounds serve as effective cyanoborane transfer agents and can be used to create neoglycoconjugates.
Area of Science:
- Organic Chemistry
- Boron Chemistry
- Synthetic Methodology
Background:
- Cyanoboranes are versatile reagents in organic synthesis.
- Alkoxyamino compounds offer unique structural motifs.
- Developing efficient methods for cyanoborane transfer is crucial.
Purpose of the Study:
- To report the novel synthesis of zwitterionic alkoxyamino cyanoboranes.
- To explore the reactivity of these new compounds as cyanoborane transfer agents.
- To investigate their application in the synthesis of neoglycoconjugates.
Main Methods:
- Reduction of O-alkyloximes using sodium cyanoborohydride.
- Isolation and characterization of zwitterionic alkoxyamino cyanoboranes and cyanoboronated N-alkoxyformamidines.
- Cyanoborane transfer reactions with various amines, including aminosugars.
- Neoglycorandomization reaction with reducing sugars.
Main Results:
- Successful synthesis of hitherto unknown zwitterionic alkoxyamino cyanoboranes.
- Isolation of cyanoboronated N-alkoxyformamidines as by-products.
- Demonstration of efficient cyanoborane transfer to basic amines and aminosugars.
- Transformation of boronated alkoxyamines into neoglycoconjugates.
Conclusions:
- The developed method provides access to novel zwitterionic alkoxyamino cyanoboranes.
- These compounds are effective cyanoborane transfer agents.
- The synthesized compounds are valuable precursors for neoglycoconjugate synthesis.
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