Crowning of Coinage Metal Pyrazolates: Double-Decker Homo- and Heteronuclear Complexes with Synergic Emissive Properties

Abstract

A new pyrazole ligand with flexible thioether chelate arms was synthesized and was used to obtain an unprecedented class of hexanuclear coinage metal complexes of general formula [MM'L]3Y3 (M, M' = Cu, Ag, Au; Y = OTf, BF4). Three of them were characterized by X-ray crystallography, namely, homometallic [Ag2L]3(OTf)3 and [Ag2L]3(BF4)3 as well as heterometallic [CuAgL]3(OTf)3, revealing that the classical [M(μ-pz)]3 core is crowned by a second deck of S-bound M' ions. Depending on the solvent, these oligonuclear systems undergo rapid dynamics and show cation-anion aggregation in solution, which has been investigated by DOSY and temperature dependent NMR spectroscopy. Preliminary luminescence data for selected hexametallic [MM'L]3Y3 complexes show that the combination of ligand-directed intramolecular and supramolecular d(10) metal ion interactions in the solid state gives rise to synergic emissive properties that allow for a selective addressing of different emission wavelengths.

Isolable arene sandwiched copper(i) pyrazolates

“…Copper(I) pyrazolates have attracted significant interest in recent years. [1][2][3][4][5][6][7][8][9][10][11][12] They show diverse structures, fascinating luminescent properties and are useful in catalysis and serve as excellent precursors for mixed ligand complexes of copper. For instance, [Cu(Pz)] n (1) (Pz = pyrazolate) is a polymer, 13 whereas { [3, 2 Pz]Cu} 3 and {[3,5-(i-Pr) 2 Pz]Cu} 3 adopt trinuclear structures 3 and {[3,5-(t-Bu) 2 Pz]Cu} 4 is a tetramer.…”

A Ferromagnetically Coupled (S=1) Peroxodicopper(II) Complex

“…To avoid forfeiting the beneficial stabilizing effect of the side arm triazacyclononane (tacn) units, we chose to follow a different strategy in the present work, namely elongation of the linkages between the central pyrazole and the tacn rings from methylene spacers in HL me to ethylene spacers in HL et (Scheme ) 16. The multistep synthesis of the new ligand HL et , starting from recently reported pyrazole building blocks,17, 18 is described in the Supporting Information.…”

The use of DOSY experiments to determine the solution structures of coinage metal pyrazolates: The case of {[3,5‐(CF3)2Pz]Ag}3

“…The study of trimeric gold(I) pyrazolate complexes started as elementary research in chemistry but quickly evolved into an applied field due to an increasing interest in their unique properties with recent applications in chemical sensing, [ 10 ] medicine, [ 11 ] liquid crystalline materials, [ 12 ] and MOFs. [ 13 ] Other coinage metals also lead to interesting applications, such as phosphorescence, [ 14 ] emissive properties, [ 15 ] catalysis, [ 16 ] olefin‐paraffin separation, [ 17–19 ] and as Buckycatchers. [ 20 ]…”