Isolation of Fluorescent 2-Aromatic 1,3-Disiladiboretenes

Herein, we reported the isolation of 2 pi-aromatic disiladiboretenes (L2Si2B2Ph2) [L = ArC((NBu)-Bu-t)(2), Ar = Ph (1), Mes (2)], which have been synthesized from the straightforward reduction of silylene-borane adducts (LSiX -> BX2Ph) [X = Cl, Br] with potassium graphite (KC8). X-ray diffraction analysis of 1 and 2 revealed that the Si2B2 units are completely planar, and DFT calculations suggested delocalization of 2 pi-electrons over the Si2B2 rings. Moreover, their photophysical properties and reactivity toward sulfur were also investigated in detail.