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10:42
Combining Solid-state and Solution-based Techniques: Synthesis and Reactivity of ChalcogenidoplumbatesII or IV
Published on: December 29, 2016
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Reductive Insertion of Elemental Chalcogens into Boron-Boron Multiple Bonds
Holger Braunschweig1, Theresa Dellermann2, William C Ewing2
1Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg (Germany). h.braunschweig@uni-wuerzburg.de.
Angewandte Chemie (International Ed. in English)
|June 30, 2015
Summary
Researchers synthesized novel sulfur and selenium cyclic compounds stabilized by N-heterocyclic carbenes (NHCs). These reactions involved reductive insertion into boron-boron multiple bonds, forming unique bicyclic and borolane structures.
Area of Science:
- Organometallic Chemistry
- Inorganic Chemistry
- Materials Science
Background:
- N-heterocyclic carbenes (NHCs) are versatile ligands in stabilizing reactive main group elements.
- Boron-boron multiple bonds offer unique reactivity for forming novel inorganic frameworks.
- Chalcogens (sulfur and selenium) are key elements for constructing diverse chemical structures.
Purpose of the Study:
- To synthesize novel sulfur- and selenium-bridged cyclic boron compounds stabilized by NHCs.
- To explore the reductive insertion of elemental chalcogens into boron-boron multiple bonds.
- To investigate the electronic properties and bonding characteristics of the resulting compounds.
Main Methods:
- Reductive insertion of elemental sulfur and selenium into boron-boron multiple bonds (diboryne and diborene).
- Stabilization of the resulting cyclic boron-chalcogen compounds using N-heterocyclic carbenes (NHCs).
- Characterization of the synthesized compounds using spectroscopic and analytical techniques.
Main Results:
- Successful synthesis of sulfur- and selenium-bridged [2.2.1]-bicyclic systems from a diboryne precursor.
- Formation of an NHC-stabilized trisulfidodiborolane from a diborene precursor.
- Demonstration of six- and four-electron reduction reactions, supporting multi-electron bonding in boron-boron multiple bonds.
Conclusions:
- The study demonstrates a novel synthetic route to NHC-stabilized cyclic boron-chalcogen compounds.
- The reactions provide evidence for multi-electron bonding in diborynes and diborenes.
- These findings contribute to the understanding of main group element chemistry and bonding.
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