title: Cyclometalated Platinum(II) Terpyridylacetylide with a Bis(arylamine) Donor as a Proton-Triggered Luminescence Chemosensor for Zn(2+).
abstract: A cyclometalated Pt(II) acetylide derivative bearing a bis(arylamine) donor (D) and a terpyridine (TPY) receptor (A) was successfully synthesized and characterized. This three-component D-π-A system displays an intense low-energy absorption band at λmax = 470 nm, resulting from overlapping the dπ(Pt) → π*(C^N^N) metal-to-ligand charge transfer and π(C≡C-Ar) → π*(C^N^N) ligand-to-ligand charge transfer transitions with the π(bis(arylamine)) → π*(C^N^N) intraligand charge transfer transition. Upon protonation of the bis(arylamine) donor, a strong emission from the phosphorescence Pt(II) complex unit is recovered at λmax = 580 nm. With introduction of the TPY receptor, this complex possesses quite high affinity for Zn(2+) (Ka = 6.86 × 10(9) mol(-2)·dm(6)) to form the heterotrinuclear Pt-Zn-Pt complex in CH2Cl2 solution. Though this coordination effect is seriously inhibited by protons in acidic medium, the 2.4-fold luminescence intensity enhancement is obtained yet, strongly suggesting the presence of the intramolecular energy transfer process from the Zn(II)-TPY complex core to the phosphorescence Pt(II) complex units at two ends. The H(+)-triggered and Zn(2+)-enhanced luminescence can be reversibly switched on and off upon successive additions of H(+) and OH(-). Furthermore, this complex displays an unexpected Zn(2+)-selective luminescence enhancement effect in acidic solution.
authors.affiliation: College of Chemistry and Pharmacy Engineering, Nanyang Normal University, Nanyang, 473061, P. R. China.
authors.forename: Dongfang
authors.initials: D
authors.lastname: Qiu
authors.affiliation: College of Chemistry and Pharmacy Engineering, Nanyang Normal University, Nanyang, 473061, P. R. China.
authors.forename: Mengmeng
authors.initials: M
authors.lastname: Li
authors.affiliation: College of Chemistry and Pharmacy Engineering, Nanyang Normal University, Nanyang, 473061, P. R. China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhao
authors.affiliation: College of Chemistry and Pharmacy Engineering, Nanyang Normal University, Nanyang, 473061, P. R. China.
authors.forename: Hongwei
authors.initials: H
authors.lastname: Wang
authors.affiliation: College of Chemistry and Pharmacy Engineering, Nanyang Normal University, Nanyang, 473061, P. R. China.
authors.forename: Chunxia
authors.initials: C
authors.lastname: Yang
mesh_terms: D000588:Amines / Q000737:chemistry*; D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D004579:Electron Transport; D008024:Ligands; D008163:Luminescent Measurements; D009944:Organoplatinum Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D011522:Protons; D011725:Pyridines / Q000737:chemistry*; D013696:Temperature; D015032:Zinc / Q000032:analysis* / Q000737:chemistry
chemical_list: D000588:Amines; D008024:Ligands; D009944:Organoplatinum Compounds; D011522:Protons; D011725:Pyridines; D015032:Zinc