A C^N Cycloplatinated(II) Fluoride Complex: Photophysical Studies and C_sp³–F Bond Formation

Abstract

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.

Synthesis, Reactivity, and Bonding of Gold(I) Fluorido–Phosphine Complexes

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Strongly Luminescent Pt(IV) Complexes with a Mesoionic N-Heterocyclic Carbene Ligand: Tuning Their Photophysical Properties

“…Transition-metal complexes featuring long-lived emissive triplet excited states are at the core of numerous technological, analytical, biomedical, and synthetic developments, including chemosensing, , cell imaging, photodynamic therapy, photocatalysis, and light-emitting materials. − Over the past decades, most research in this area has focused on luminescent Ir­(III) − and Pt­(II) − complexes with cyclometalating heteroaromatic ligands because of the high tunability and adaptability of their excited states, whereas Pt­(IV) complexes have only started to be systematically explored as strong emitters in recent years. − …”

Platinum Indolylphosphine Fluorido and Polyfluorido Complexes: An Interplay between Cyclometallation, Fluoride Migration, and Hydrogen Bonding

“…described the preparation of Pt( ii ) fluorido complexes by a F/I exchange reaction with AgF. [ 1d , 1e , 6l ] Platinum fluorido complexes were also obtained by reaction of hydrogen fluoride sources with platinum hydrido or dimethyl complexes, as shown by Perutz et al. and Seppelt et al., respectively.…”