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

Herein, we reported the isolation of 2π-aromatic disiladiboretenes (L 2 Si 2 B 2 Ph 2 ) [L = ArC(N t Bu) 2 , Ar = Ph ( 1 ), Mes ( 2 )], which have been synthesized from the straightforward reduction of silylene-borane adducts (LSiX → BX 2 Ph) [X = Cl, Br] with potassium graphite (KC 8 ). X-ray diffraction analysis of 1 and 2 revealed that the Si 2 B 2 units are completely planar, and DFT calculations suggested delocalization of 2π-electrons over the Si 2 B 2 rings. Moreover, their photophysical properties and reactivity toward sulfur were also investigated in detail.