Isolation of Fluorescent 2π-Aromatic 1,3-Disiladiboretenes

Area of Science:

• Organometallic Chemistry
• Materials Science
• Inorganic Chemistry

Background:

• Organoboron and organosilicon compounds are crucial in various chemical applications.
• Aromaticity in low-valent silicon-boron systems remains an area of active research.
• Exploring novel ring systems with unique electronic properties is essential for advancing chemical synthesis.

Purpose of the Study:

• To synthesize and characterize novel 2π-aromatic disiladiboretenes.
• To investigate the structural and electronic properties of these compounds.
• To explore their reactivity, particularly towards sulfur.

Main Methods:

• Synthesis via straightforward reduction of silylene-borane adducts using potassium graphite (KC8).
• Structural characterization using X-ray diffraction analysis.
• Computational investigation using Density Functional Theory (DFT) calculations.

Main Results:

• Isolation of 2π-aromatic disiladiboretenes (L2Si2B2Ph2) where L = ArC(NBu2)2, Ar = Ph (1), Mes (2).
• X-ray diffraction confirmed completely planar Si2B2 units in compounds 1 and 2.
• DFT calculations indicated delocalization of 2π-electrons over the Si2B2 rings.

Conclusions:

• The successful synthesis and characterization of planar 2π-aromatic disiladiboretenes represent a significant advancement in silicon-boron chemistry.
• The observed electron delocalization highlights the aromatic nature of the Si2B2 ring system.
• Further investigation into their photophysical properties and reactivity is warranted for potential applications.