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Disulfides, imines, and metal coordination within a single system: interplay between three dynamic equilibria.
Rupam J Sarma1, Sijbren Otto, Jonathan R Nitschke
1Department of Chemistry, University of Cambridge, Lensfield Road Cambridge, CB2 1EW, UK.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|September 20, 2007
Summary
This study demonstrates the simultaneous reversible exchange of disulfide, imine, and coordinative bonds. Metal salts and covalent exchange predictably altered disulfide bond equilibria, showcasing linkage compatibility.
Area of Science:
- Supramolecular Chemistry
- Dynamic Covalent Chemistry
- Coordination Chemistry
Background:
- Dynamic covalent chemistry utilizes reversible bonds to create adaptable materials.
- Simultaneous manipulation of multiple dynamic bond types remains a challenge in materials science.
Purpose of the Study:
- To investigate the simultaneous reversible exchange of disulfide, imine, and coordinative bonds.
- To demonstrate the compatibility and interplay between these distinct dynamic linkages.
- To explore the predictable perturbation of disulfide bond equilibria via metal complexation and covalent exchange.
Main Methods:
- Synthesis of homo- and hetero-disulfides.
- Catalytic disulfide exchange using triethylamine.
- Perturbation of disulfide equilibrium by 2-formylpyridine and metal salts (CuI, FeII).
- Demonstration of transmetallation and imine exchange reactions.
Main Results:
- Achieved simultaneous reversible exchange of disulfide, imine, and coordinative bonds.
- Metal complexation with CuI and FeII significantly shifted disulfide equilibria towards homo-disulfides.
- Demonstrated predictable control over disulfide equilibria through metal substitution (transmetallation) and amine exchange (imine exchange).
Conclusions:
- The three dynamic linkages (disulfide, imine, coordinative) are mutually compatible.
- Changes in one linkage type can predictably influence equilibria involving other linkages.
- This system offers a platform for designing sophisticated adaptive materials.
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