Silver(I) and gold(I) complexes with tris[2-(2-pyridyl)ethyl]phosphine

Metal Complexes Containing Homoleptic Diorganoselenium(II) Ligands: Synthesis, Characterization and Investigation of Optical Properties

[(Z)-2'-{2-C6H5-(4H)-oxazol-5-one}CHC6H4]2Se (5, L1) and [(Z)-4'-{2-C6H5-(4H)-oxazol-5-one}CHC6H4]2Se (6, L2) were prepared, structurally characterized and used as ligands to obtain new metal complexes of types [MX(Ln)] [L1: M = Ag, X = OTf (7); M = Au, X = Cl (13); L2: M = Ag, X = OTf (8); M = Au, X = Cl (14)], [(MX)2(Ln)] [M = Ag, X = OTf, L1 (9); L2 (10)], [ZnCl2(Ln)] [L1 (15); L2 (16)] and [Ag(Ln)][PF6] [L1 (11); L2 (12)]. The silver complexes 7 and 8 were ionic species (1:1 electrolytes) in a MeCN solution, while in the solid state, the triflate fragments were bonded to the silver cations. Similarly, the 2:1 complexes 9 and 10 were found to behave as 1:2 electrolytes in a MeCN solution, but single-crystal X-ray diffraction demonstrated that compound 9 showed the formation of a dimer in the solid state: a tetranuclear [Ag(OTf)]4 built through bridging triflate ligands was coordinated by two bridging organoselenium ligands through the nitrogen from the oxazolone ring and the selenium atoms in a 1κN:2κSe fashion. Supramolecular architectures supported by intermolecular C-H∙∙∙π, C-H∙∙∙O, Cl∙∙∙H and F∙∙∙H interactions were observed in compounds 4, 5 and 9. The compounds exhibited similar photophysical properties, with a bathochromic shift in the UV-Vis spectra caused by the position of the oxazolone ring on the phenyl ring attached to the selenium atoms.

Phosphorus or Nitrogen - The first Phosphatriptycene in Coordination Polymer Chemistry

Phosphasilatriptycene, a phenylene spacer and a pyridyl moiety represent the building blocks of TRIP-Py, the first heteroditopic ligand featuring a phoshatriptycene scaffold. The P and N donor sites located at...

Synthesis, crystal structure and photophysical properties of bis-[2,6-di-fluoro-3-(pyridin-2-yl)pyridine-κN](tri-fluoro-methane-sulfonato-κO)silver(I)

In the title compound, [Ag(CF3SO3)(C10H6F2N2)2], the AgI centre adopts a highly distorted trigonal-planar coordination environment resulting from its coordination by one O atom of the tri-fluoro-methane-sulfonate anion and the pyridine N atoms of two crystallographically independent 2',6'-di-fluoro-2,3'-bi-pyridine ligands, which display very similar conformations to one another. Pairwise Ag⋯O-SO2CF3 - [Ag⋯O = 2.8314 (14) Å] inter-actions and inter-molecular C-H⋯O inter-actions between inversion-related units lead to the formation of an eight-membered cyclic dimer in which the silver atoms are separated by 6.2152 (3) Å. In the crystal, the dimers are linked through C-H⋯O hydrogen bonds, halogen⋯π and weak π-π stacking inter-actions, resulting in the formation of a three-dimensional supra-molecular network. The title compound exhibits a strong and broad emission band from 400 nm to 550 nm in solution and its photoluminescence quantum efficiency is estimated to be ca 0.2, indicating that the title compound could have applications as an emitting material in organic light-emitting diodes (OLEDs).

Intramolecular aurophilic interactions in dinuclear gold(I) complexes with twisted bridging 2,2'-bipyridine ligands

Elimination of the chloride ion from the [(PPh₃)AuCl] complex using silver triflate (AgOTf) in the presence of 2,2'-bipyridine R₂bpy (the Au : R₂bpy molar ratio is 2 : 1) in dichloromethane at room temperature leads to dinuclear gold(I) complexes [(PPh₃Au)₂(μ-R₂bpy)](OTf)₂ (R₂bpy = bpy (1), dbbpy (2), CH₃Obpy (3), 3-CO₂CH₃bpy (4), 4-CO₂CH₃bpy (5)) in high yields. The crystal structures for all compounds were determined using X-ray diffraction analysis. In all structures, gold ions are in a typical linear environment, and the bipyridine molecule is twisted, which allows intramolecular aurophilic interactions. Relatively short Au(I)⋯Au(I) contacts (3.1262 (2)-3.400 (1) Å) are found in structures 3-5. DFT calculations show the presence of bond critical points (3, -1) for aurophilic interactions in these structures. In structures 1 and 2, the Au(I)⋯Au(I) distances are noticeably larger and equal to 4.479 (1) and 4.589 (1) Å respectively; there are no bond critical points (3, -1) for aurophilic interactions. All complexes show photoluminescence in solid state at room temperature when excited at 300 nm in a wide spectral range: from blue or blue-green emission (400-460 nm) for 1-4 to orange emission (580 mn) for 5. The lifetimes of the excited state are in the microsecond range which is characteristic of phosphorescence. TD-DFT calculations reveal that electronic transitions of different nature are responsible for the photoluminescence of these compounds.

Excitation wavelength dependent emission of silver(i) complexes with a pyrimidine ligand

Interplay of three emission mechanisms for silver(i) complexes leads to luminescence thermochromism and color tunable emission.

Harvesting greenish blue luminescence in gold(i) complexes and their application as promising bioactive molecules and cellular bioimaging agents

This work presents new gold materials as promising antitumoral and antibacterial agents and their potential use as luminescent probes for cellular bioimaging.

Sky-blue thermally activated delayed fluorescence (TADF) based on Ag(i) complexes: strong solvation-induced emission enhancement

Remarkable solvation-induced emission enhancement is discovered on a new Ag(i) complex showing sky-blue thermally activated delayed fluorescence (TADF).