A C^N Cycloplatinated(II) Fluoride Complex: Photophysical Studies and Csp3-F Bond Formation.

This work reports the synthesis and characterization of a new C^N-based cycloplatinated(II) fluoride complex, [Pt(ppy)(PPh3)F] (2; ppy = 2-phenylpyridinate), involving a Pt-F bond. The new complex is highly luminescent in the green area with a high quantum yield of 94.6% at 77 K. A comparison study of the heavier halogen derivatives reveals a descending emission quantum yield order of F > Cl > Br > I. Time-dependent density functional theory calculations ascribe the decreased emission efficiency to the decreasing trend of an intraligand (IL) transition from F to I, which accounts for the major radiative pathway. In addition, 2 is capable of the fluorinating alkyl halides, leading to Csp3-F bond formation at room temperature.