Harnessing the electronic differences between CAAC-stabilised 1,4-diborabenzene and 9,10-diboraanthracene for...

Area of Science:

• Organoboron Chemistry
• Heterocyclic Chemistry
• Materials Science

Background:

• Cyclic alkyl(amino)carbene-stabilised diborabenzenes and diboraanthracenes are unique organoboron compounds.
• Understanding their reactivity with oxidising agents is crucial for developing new synthetic methodologies and materials.

Purpose of the Study:

• To investigate the oxidation reactions of closed-shell 1,4-diborabenzenes and open-shell 9,10-diboraanthracene.
• To characterise the resulting sulfur-, selenium-, and oxygen-bridged heterocyclic compounds.

Main Methods:

• Oxidation reactions using elemental sulfur, selenium, and molecular oxygen.
• Spectroscopic characterisation (NMR, Mass Spectrometry) and X-ray crystallography of the products.

Main Results:

• Oxidation of 1,4-diborabenzenes with S or Se yielded S4/S5- or Se4-bridged hexa-1,4-dienes.
• Oxidation of 9,10-diboraanthracene with O2, S, or Se produced endoperoxo- or S/Se-bridged bicyclic species.

Conclusions:

• The study demonstrates selective oxidation pathways for diborabenzenes and diboraanthracenes.
• Novel sulfur-, selenium-, and oxygen-bridged organoboron heterocycles were successfully synthesised and characterised.