Reductive cyclization cascades of lactones using SmI2-H2O
Dixit Parmar1, Kieran Price, Malcolm Spain
1School of Chemistry, University of Manchester, Manchester, United Kingdom.
Journal of the American Chemical Society
|February 11, 2011
Summary
This study introduces a new method for synthesizing azulene structures using reductive cyclization. The process efficiently creates complex azulene motifs from lactones with high yield and stereochemical control.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Methodology Development
Background:
- Azulene motifs are valuable in medicinal chemistry and materials science.
- Efficient synthesis of substituted azulenes remains a challenge.
Purpose of the Study:
- To develop a novel synthetic route to decorated azulene motifs.
- To explore the utility of reductive cyclization cascades for azulene synthesis.
Main Methods:
- Treatment of lactones bearing two alkenes or an alkene and an alkyne with samarium(II) iodide (SmI2) and water.
- Reductive cyclization cascade reactions.
Main Results:
- Excellent yields of decorated azulene motifs were achieved.
- Good diastereocontrol was observed in the cyclization process.
- The method is applicable to lactones with diverse unsaturation patterns.
Conclusions:
- Reductive cyclization cascades using SmI2-H2O provide an effective strategy for constructing complex azulene structures.
- This methodology offers a new pathway for accessing valuable azulene derivatives.
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