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Lewis acid-catalyzed domino generation/[2,3]-sigmatropic rearrangement of ammonium ylides to access chiral azabicycles
- Source :
- Science Advances
- Publication Year :
- 2020
-
Abstract
- A domino process to prepare chiral azabicycles with bridgehead quaternary stereogenic centers is reported.<br />[2,3]-Sigmatropic rearrangement of ammonium ylides represents a fundamental reaction for stereoselective synthesis of nitrogenous compounds. However, its applicability is limited by the scarcity of efficient, catalytic, and mild methods for generating ammonium ylides. Here, we report silver-catalyzed domino generation/[2,3]-sigmatropic rearrangement of ammonium ylides, furnishing chiral azabicycles with bridgehead quaternary stereogenic centers in high enantiomeric purity (up to 99% ee). A combination of density functional theory calculations and experimental studies revealed that residual water in the reaction system is crucial for the mild reaction conditions by functioning as a proton shuttle to assist carbon-silver bond protonation and C2─H deprotonation to generate the ammonium ylide. This reaction has a broad application scope. Besides the diverse substituents, N-fused azabicycles of various ring sizes are also easily accessed. In addition to silver salts, this strategy has also been successfully implemented by using a stoichiometric amount of nonmetallic I2.
- Subjects :
- chemistry.chemical_classification
Multidisciplinary
010405 organic chemistry
2,3-sigmatropic rearrangement
Organic Chemistry
SciAdv r-articles
Protonation
010402 general chemistry
01 natural sciences
Combinatorial chemistry
0104 chemical sciences
Stereocenter
Catalysis
chemistry.chemical_compound
Deprotonation
chemistry
Ylide
Ammonium
Lewis acids and bases
Research Articles
Research Article
Subjects
Details
- ISSN :
- 23752548
- Volume :
- 7
- Issue :
- 5
- Database :
- OpenAIRE
- Journal :
- Science advances
- Accession number :
- edsair.doi.dedup.....222208c8061383c3bc08bcc2b22e49e1