Synthesis, Optical Properties, and Reactivities of A Dibenzophosphaborin and Its Derivatives.

Dibenzo-1,4-phosphaborins were synthesized and characterized by X-ray crystallographic analysis. The phosphaborins exhibited UV/vis absorption derived from intramolecular charge transfer from the phosphorus atom to the boron atom. The phosphaborins showed different fluorescent properties depending on the substituents on the phosphorus atom. The phosphaborin was easily derivatized to P-sulfide, P-selenide and phosphonium salt. The phosphaborin and its P-derivatives formed complexes with fluoride ion. The complex formation constants were shown to increase in accordance with the decrease in their LUMO energy levels. [ABSTRACT FROM AUTHOR]