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Exploring hydroamination-cycloaddition-fragmentation sequences to access polycyclicguanidines and
Ki-Hyeok Kwon1, Anne V Edwards1, Miao Yang1
1Department of Chemistry, University of Utah 315 S 1400 E, Salt Lake City, UT 8103, USA.
Tetrahedron
|April 24, 2018
Summary
A novel intramolecular hydroamination reaction creates guanidine-substituted dienes. These dienes participate in cycloaddition reactions, yielding complex guanidines and enabling synthesis of natural products.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Guanidine functional groups are prevalent in biologically active molecules.
- Efficient synthetic routes to complex guanidine structures are valuable.
Purpose of the Study:
- To develop a novel synthetic method for constructing guanidine-substituted dienes.
- To explore the reactivity of these dienes in cycloaddition reactions.
- To investigate cascade reactions for accessing complex guanidines and related structures.
Main Methods:
- Intramolecular hydroamination of eneyne substrates bearing a guanidine moiety.
- Diels-Alder ([4+2]-cycloaddition) reactions with dienophiles.
- Ring opening-elimination cascade reactions.
Main Results:
- The intramolecular hydroamination successfully generated guanidine-substituted dienes.
- These dienes reacted with dienophiles to form diverse cyclic- and spirocyclic-guanidines.
- A cascade pathway was identified, leading to vinyl-2-aminoimidazoles.
Conclusions:
- A new synthetic strategy for guanidine-containing compounds has been established.
- The developed methodology provides access to complex guanidines and vinyl-2-aminoimidazoles.
- This approach holds potential for the synthesis of oroidin-type natural products and analogues.
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