CAAC-stabilised 9,10-diboraanthracene: an electronically and structurally flexible platform for small-molecule
Maximilian Dietz1,2, Merle Arrowsmith1,2, Holger Braunschweig1,2
1Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany. h.braunschweig@uni-wuerzburg.de.
Dalton Transactions (Cambridge, England : 2003)
|December 8, 2023
Summary
A novel cyclic alkyl(amino)carbene-stabilised 9,10-diboraanthracene (DBA) activates small molecules and forms new half-sandwich complexes with transition metals. This research advances organoboron chemistry and coordination complexes.
Area of Science:
- Organometallic Chemistry
- Boron Chemistry
- Small Molecule Activation
Background:
- Carbene-stabilised 9,10-diboraanthracenes (DBAs) are emerging as versatile platforms in synthetic chemistry.
- Understanding their reactivity with small molecules and transition metals is crucial for developing new catalytic systems and materials.
Purpose of the Study:
- To investigate the small molecule activation capabilities of a specific biradical cyclic alkyl(amino)carbene-stabilised DBA.
- To synthesize and characterize the first half-sandwich DBA complexes with group 6 metals.
Main Methods:
- Reaction of the DBA with small molecules including hydrogen, phenyl azide, and TEMPO.
- Complexation reactions with [(MeCN)3M(CO)3] where M = Cr, Mo, W.
Main Results:
- The DBA successfully activated hydrogen, phenyl azide, and TEMPO across its boron atoms.
- The first half-sandwich DBA complexes, [(η6-DBA)M(CO)3], were synthesized and characterized.
Conclusions:
- The studied DBA exhibits significant reactivity towards small molecule activation.
- This work introduces a new class of half-sandwich organometallic complexes with potential applications in catalysis.
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