Photofunctional platinum complexes featuring N-heterocyclic carbene-based pincer ligands

Abstract

Photoactive platinum complexes of stoichiometry [Pt((R)CCC(R))L](0/+) (R = Me, nBu and L = -CN, -C≡CPh, -N≡CCH3, -Py, -CO) featuring pincer-type bis N-heterocyclic carbene (NHC) ligands ((R)CCC(R)) were synthesized. Organometallic syntheses of these complexes are facile and achievable through standard laboratory procedures. Control of intermolecular Pt⋅⋅⋅Pt interaction, π-π stacking, and emission tuning is achieved through suitable choice of the NHC-wingtip substituent (R) and the auxiliary ligand (L). Exposure to specific volatile organic compounds (VOCs) or mechanical grinding triggers changes in emission colors, which render these complexes photofunctional. Solid-state structures and photoluminescence results are described herein.

Keywords: N-heterocyclic carbene complexes; photoactive platinum complexes; stimuli-responsive emission.