α-Carbonyl Cations in Sulfoxide-Driven Oxidative Cyclizations.
Tobias Stopka1, Meike Niggemann1, Nuno Maulide2
1Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany.
Angewandte Chemie (International Ed. in English)
|August 24, 2017
Summary
This study presents a metal-free method for creating α-carbonyl cations from alkynes. These reactive intermediates enable the synthesis of complex molecules with congested carbon centers in one step.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Metal-free synthetic strategies are crucial for sustainable chemistry.
- Vinyl cations are important intermediates in organic synthesis.
Purpose of the Study:
- To develop a selective, metal-free method for generating α-carbonyl cations.
- To explore the reactivity of these cations in complex molecule synthesis.
Main Methods:
- Addition of sulfoxides to densely substituted vinyl cations.
- Mechanistic analysis to understand reaction pathways.
Main Results:
- Successful generation of α-carbonyl cations from simple internal alkynes.
- Demonstrated high reactivity leading to hydrogen and carbon shifts with unusual selectivities.
- Synthesis of complex compounds with congested tertiary and quaternary carbon centers in a single step.
Conclusions:
- The developed method provides efficient access to valuable synthetic intermediates.
- The study offers a predictive scheme for substituent migratory aptitude in these reactions.
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