Synthesis, Characterization, Photoluminescence, and Simulations of a CCC-NHC-Supported Pt2Ag2 Mixed-Metal Cluster Containing a PtAg2 Metallacyclopropane

Influence of the Steric/Electronic Properties of N-Aryl Substituents in Cycloplatinated Guanidinate(1-) Complexes on the Formation of Discrete Pt → Ag Complexes and One-Dimensional Coordination Polymer

The reactions of cycloplatinated guanidinate(1-) complexes 1-6 with AgTFA (TFA = OC(O)CF₃) in 1:1 and 1:2 Pt^II/Ag^I molar ratios afforded complexes containing three types of Pt₂Ag₂ skeletons (7-10, 11, and 13), one 1D CP containing Pt₂Ag₃ skeleton (16), and a Pt₂Ag₄ complex (17) in 91-95% (method 1), 73-82% (method 2) (7-10), and 54-79% (11, 13, 16, and 17) yields. The reactions of 11 with 2,6-XylNC (2,6-Xyl = 2,6-Me₂C₆H₃) and 4-DMAP (4-dimethylaminopyridine) gave a neutral complex 18 and an ionic complex 19, respectively. Molecular structures of 12 complexes were unambiguously determined by single-crystal X-ray diffraction. Ten complexes contain unprecedented PtAg skeletons and are shown to contain multiple number of dative Pt → Ag bonds supported by the TFA ligand, platinated carbon of the TAG ligand, or both these ligands in conjunction with the Ag-Ag contacts stabilized by argentophilic interaction. Further, the new complexes were characterized by analytical, IR, and multinuclear NMR (¹⁹F, ¹H, ¹³C{¹H}, and ¹⁹⁵Pt) spectroscopies, powder X-ray diffraction, and TGA/DTA. In solution, 9 and 19 exist in more than one form as identified by multinuclear NMR, and this behavior is ascribed to the restricted (N₂)C-N(H)Ar single-bond rotation of the TAG ligand. The photophysical properties of 9 and 11 are reported.

NHC stabilized Pd nanoclusters in the Mizoroki–Heck reaction within microemulsion: exploring the role of imidazolium salt in rate enhancement

Significant rate enhancement of the Mizoroki–Heck reaction by in situ generated palladium nanoclusters within the confined space of water-in-oil mixed microemulsion in the presence of novel imidazo[1,5-α]pyridinium chlorides as N-heterocyclic carbene (NHC) precursors is reported.

U- to Z-shape isomerization in a Pt2Ag2 framework containing pyridyl-NHC ligands

A highly twisted U-shaped Pt₂Ag₂ complex bearing pyridyl–NHC ligands showed isomerization to Z-shaped conformations via an intermolecular process. ¹H NMR experiments revealed that the isomerization reached U : Z = 2 : 1 ratio in a thermodynamic equilibrium state.

Metal complexes with di(N-heterocyclic carbene) ligands bearing a rigid ortho-, meta or para-phenylene bridge

Ag(i) complexes with diNHC ligands are efficient transmetalating agents towards transition metals.

Monoanionic bis(carbene) pincer complexes featuring cobalt(I–III) oxidation states

The synthesis and characterization of a series of cobalt complexes featuring a pincer bis(carbene) ligand of the meta-phenylene-bridged bis-N-heterocyclic carbene (^ArCCC, Ar = 2,6-diispropylphenyl or mesityl) are reported.

Induced phosphorescence from Pt → Ag and Ag(i)⋯Ag(i) metallophilic interactions in benzenedithiolatodiimine-Pt2/Ag2 clusters: a combined experimental and theoretical investigation

We report the synthesis and luminescence properties of a novel platinum(ii)–silver(i) cluster exhibiting supramolecular donor–acceptor dative Pt → Ag bonds as well as d¹⁰⋯d¹⁰ argentophilic interactions.

Synthesis, characterization, photophysical properties, and catalytic activity of an SCS bis(N-heterocyclic thione) (SCS-NHT) Pd pincer complex

Treatment of 1,3-bis(3'-butylimidazolyl-1'-yl)benzene diiodide with elemental sulfur in the presence of a base produced a bis(N-heterocyclic thione) (NHT) pincer ligand precursor. Its reaction with PdCl2(CH3CN)2 produced chloro[1,3-bis(3'-butylimidazole-2'-thione-κ-S)benzene-κ-C]palladium(ii), a 6,6-fused ring SCS-NHT palladium pincer complex. This air stable compound is, to our knowledge, the first SCS pincer complex that utilizes N-heterocyclic thione (NHT) donor groups. The molecular structures of the ligand precursor and the palladium complex were determined by X-ray crystallography and computational studies provided insight into the interconversion between its rac and meso conformations. The photophysical properties of the complex were established, and its catalytic activity in Suzuki, Heck, and Sonogashira cross-coupling reactions was evaluated.

Self-assembly of a neutral platinum(ii) complex into highly emitting microcrystalline fibers through metallophilic interactions

The solvent-assisted self-assembly of a blue-emitting neutral platinum(ii) complex into micrometer-long and highly crystalline fibers has been achieved.

N-heterocyclic carbene metal complexes: photoluminescence and applications

This review covers the advances made in the synthesis and applications of luminescent transition metal complexes containing N-heterocyclic carbene (NHC) ligands.

When self-assembly meets biology: luminescent platinum complexes for imaging applications

Self-assembled luminescent structures based on platinum complexes. A new tool for bioimaging?