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Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
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Cobalt-Catalyzed Intermolecular [2+2] Cycloaddition between Alkynes and Allenes.
1Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore.
Angewandte Chemie (International Ed. in English)
|January 8, 2019
Summary
A novel cobalt-catalyzed [2+2] cycloaddition reaction efficiently synthesizes 3-alkylidenecyclobutene derivatives from alkynes and allenes. This method offers high yield and regioselectivity, accommodating diverse functional groups.
Area of Science:
- Organic Chemistry
- Catalysis
- Cycloaddition Reactions
Background:
- Intermolecular [2+2] cycloaddition reactions are fundamental in organic synthesis.
- Developing efficient catalytic systems for cycloadditions remains a key research area.
Purpose of the Study:
- To report a novel intermolecular [2+2] cycloaddition reaction between alkynes and allenes.
- To develop a cobalt(I)/diphosphine catalyzed method for synthesizing 3-alkylidenecyclobutene derivatives.
Main Methods:
- Utilizing a cobalt(I)/diphosphine catalyst system.
- Reacting near equimolar mixtures of various internal alkynes and mono- or disubstituted allenes.
Main Results:
- Achieved good yields and high regioselectivity in the formation of 3-alkylidenecyclobutene derivatives.
- Demonstrated tolerance for a wide range of functional groups on both alkyne and allene substrates.
- Proposed a reaction mechanism involving oxidative cyclization and reductive elimination.
Conclusions:
- The developed cobalt-catalyzed reaction provides an efficient route to 3-alkylidenecyclobutene derivatives.
- The methodology is versatile, accommodating diverse substrates and functional groups.
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