Di‐ and Trinuclear Gold Complexes of Diphenylphosphinoethyl‐Functionalised Imidazolium Salts and their N‐Heterocyclic Carbenes: Synthesis and Photophysical Properties

Abstract

Diphenylphosphinoethyl-functionalised imidazolium salts and their silver-carbene complexes were used to synthesise a series of di- and trinuclear gold complexes through ligand exchange and transmetallation, respectively. Besides a few positively charged macrocyclic compounds with different anions (both with and without activation of the carbene function), we were able to obtain neutral polynuclear complexes by varying the gold precursor. The synthesised gold complexes show a variety of photophysical properties, including bright white photoluminescence at ambient temperature.

Alkynyl-functionalized gold NHC complexes and their coinage metal clusters

“…Nowadays, NHCs are widely used in organometallic synthesis to establish novel complexes, which can be investigated in terms of their catalytic 5,6 or photophysical 7,8 properties. One particular advantage of NHCs is their broad variety as many different substituents can be attached to the nitrogen atoms.…”

“…24-26 Given our 7 and others' 27, 28 interest in polynuclear coinage metal complexes, we intended to extend our studies from phosphine-functionalized NHCs to alkynyl-functionalized carbene complexes aiming for the synthesis of heteronuclear clusters. A combination of goldmetal bonds, enabled by the relativistic effects of gold, and alkynyl groups attached to a carbene complex, should facilitate the synthesis of oligomeric or supramolecular coinage metal assemblies.…”

Remarkable catalytic activity of dinitrogen-bridged dimolybdenum complexes bearing NHC-based PCP-pincer ligands toward nitrogen fixation

“…One is the complex bearing methylene linkers between the NHC skeleton and the phosphorus atom, where a similar PCP-pincer ligand bearing two phenyl groups on each phosphorus atom has quite recently been reported by Rieger and co-workers49. The other is the complex bearing ethylene linkers, where similar PCP-pincer ligands bearing two phenyl groups on each phosphorus atom have already been reported by some research groups505152535455.…”

Recent Advances in Phosphorescent Pt(II) Complexes Featuring Metallophilic Interactions: Properties and Applications

“…Furthermore, the electronic properties of both metal center and substituents onto the coordinated ligands allow easy addressable modulation of both redox and emission properties with luminescence colors adjustable over the entire visible spectrum and beyond. 2,8,9 Also, for derivatives based on the second and third row of the transition metal block, such as d 6 Ir(III), Ru(II), Os(II), and Re(I), as well as d 8 Pt(II) and Au(III), 18,19 and d 10 Au(I), 20,21 the sizeable spinorbit coupling effect induced by the heavy atom promotes fast and efficient intersystem crossing process between singletand triplet-manifold electronic states, yielding triplet excited states with radiative rate constants (k r ) capable of efficiently competing with the radiationless deactivation pathways (k nr ).…”