Synthesis, structure and density functional theory calculations of a novel photoluminescent trisarylborane-bismuth(III) complex.

A novel trisarylborane-Bi(III) complex, tris(4-(dimesitylboryl)phenyl)bismuthine [Bi(PhBMes ) ], in which (Ph = phenyl, and Mes = mesityl), was synthesized via the reaction of bismuth (III) chloride (BiCl ) with three equivalents of lithiated (4-bromophenyl)- dimesitylborane [BrPhBMes ]. The new trisarylbismuthine was characterized by elemental analysis, ultraviolet-visible (UV-vis) spectroscopy, and NMR ( H and C) spectroscopy. The molecular structure of Bi(PhBMes ) in the solid state was determined using single-crystal X-ray diffraction analysis, which showed short intermolecular C-H···H-C contact. The complex is a fluorescent emitter (λ  = 395 nm) at room temperature and a phosphorescent emitter (λ  = 423 nm) at 77 K, which displayed a long lifetime of 495 ms. The UV-vis transitions were investigated using density function theory (DFT) and time-dependent (TD)-DFT calculations. Natural bond orbital analysis showed that the bismuth (III) center was mainly Lewis acidic in nature.