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Alkyne mechanochemistry: putative activation by transoidal bending.
Charles E Diesendruck1, Lingyang Zhu, Jeffrey S Moore
1Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, USA. jsmoore@illinois.edu.
Chemical Communications (Cambridge, England)
|August 7, 2014
Summary
Mechanical stress bends carbon-carbon triple bonds, forming isoquinoline via nucleophilic addition. This mechanochemical trans-bending differs from typical cisoidal bending in strained alkynes.
Area of Science:
- Organic Chemistry
- Mechanochemistry
- Materials Science
Background:
- Carbon-carbon triple bonds are fundamental in organic synthesis.
- Understanding the reactivity of strained alkynes is crucial for developing new synthetic methodologies.
- Mechanochemistry offers a unique approach to induce chemical transformations.
Purpose of the Study:
- To investigate the application of mechanical stress in manipulating carbon-carbon triple bonds.
- To elucidate the reaction mechanism of mechanochemically induced triple bond bending.
- To differentiate this novel reactivity from known pathways in strained cyclic alkynes.
Main Methods:
- Application of mechanical stress to induce bending of carbon-carbon triple bonds.
- Utilizing a benzyl azide trap to capture reaction intermediates.
- Spectroscopic analysis to identify reaction products and elucidate mechanisms.
Main Results:
- Successful induction of mechanical stress to bend carbon-carbon triple bonds.
- Formation of an isoquinoline product upon reaction with benzyl azide.
- Evidence for a nucleophilic addition mechanism in the mechanochemical process.
Conclusions:
- Mechanical stress can induce trans-bending of π bonds in carbon-carbon triple bonds.
- The observed reactivity proceeds via a nucleophilic addition pathway.
- This mechanochemical approach offers a distinct reactivity profile compared to traditional methods involving strained cyclic alkynes.
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