Structural complexity through multicomponent cycloaddition cascades enabled by dual-purpose, reactivity regenerating
Paul A Wender1, Dennis N Fournogerakis2, Matthew S Jeffreys2
1Department of Chemistry, Department of Chemical and Systems Biology, Stanford University, Stanford, California 94305-5080, USA.
Nature Chemistry
|April 24, 2014
Summary
Researchers developed a novel multicomponent reaction using a 1,2,3-butatriene equivalent (TMSBO) that efficiently synthesizes complex polycycles. This yne-to-diene transmissive reagent enables sequential cycloadditions for streamlined synthesis.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Reaction Methodology
Background:
- Multicomponent reactions offer efficient synthesis of complex molecules.
- Relaying reactivity through multiple intermediates is key in complex syntheses.
- Simple starting materials can be converted to value-added targets economically.
Purpose of the Study:
- To report a novel multicomponent process for synthesizing polycycles.
- To introduce a new 1,2,3-butatriene equivalent as a synthetic reagent.
- To couple two powerful cycloaddition reactions via a novel elimination pathway.
Main Methods:
- A novel 1,2,3-butatriene equivalent (TMSBO) was employed.
- Metal-catalyzed [5 + 2] cycloaddition with vinylcyclopropane was performed.
- Subsequent 1,4-Peterson elimination and [4 + 2] cycloaddition were utilized.
Main Results:
- TMSBO acted as a two-carbon alkyne component in a [5 + 2] cycloaddition.
- A rapid 1,4-Peterson elimination generated a diene intermediate.
- The diene intermediate was intercepted by a subsequent [4 + 2] cycloaddition, forming polycycles.
Conclusions:
- TMSBO functions as an yne-to-diene transmissive reagent.
- This method effectively couples Diels-Alder and homologous Diels-Alder reactions.
- The process provides flexible access to diverse polycyclic structures.
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