[4+2+2] Cycloaddition catalyzed by a new cationic rhodium-bisphosphine monooxide complex
Gino Martin R Canlas1, Scott R Gilbertson
1Department of Chemistry, University of Houston, Houston, TX 77204, USA. srgilbertson@UH.edu.
Chemical Communications (Cambridge, England)
|April 8, 2014
Summary
A novel rhodium-BozPHOS complex efficiently catalyzes [4+2+2] cycloisomerization reactions of cyclooctatrienes. This study details the complex
Area of Science:
- Organometallic Chemistry
- Catalysis
- Organic Synthesis
Background:
- Cycloaddition reactions are fundamental in organic synthesis.
- Cyclooctatrienes are versatile substrates for complex molecular architectures.
- Development of efficient catalytic systems for cycloisomerization is ongoing.
Purpose of the Study:
- To report a new rhodium-BozPHOS based complex.
- To evaluate its catalytic activity in [4+2+2] cycloisomerization of cyclooctatrienes.
- To elucidate the structural features of the catalyst.
Main Methods:
- Synthesis and characterization of a rhodium-BozPHOS complex.
- Catalytic testing of the complex in [4+2+2] cycloisomerization reactions.
- X-ray crystallography for structural determination.
Main Results:
- The rhodium-BozPHOS complex effectively catalyzes the target reaction.
- Moderate to good yields of cyclized products were achieved.
- Formation of both bicyclic and tricyclic products was observed.
- The X-ray crystal structure of the complex was determined.
Conclusions:
- A new rhodium-BozPHOS complex is a competent catalyst for [4+2+2] cycloisomerization.
- The catalyst enables the synthesis of complex bicyclic and tricyclic structures.
- Structural insights aid in understanding the catalytic mechanism.
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