Alkynyl-functionalized gold NHC complexes and their coinage metal clusters

Abstract

Phenylpropynyl-functionalized imidazolium salts, as well as their gold complexes, were prepared in excellent yields affording suitable starting materials for metal cluster synthesis. The reactions of these gold complexes with coinage metal phenylacetylides [M(CCPh)](x) (M = Cu, Ag) resulted in the formation of novel heterometallic hexanuclear clusters which exhibit mixed metallophillic interactions and intense white photoluminescence at low temperature.

Coinage Metal Complexes of Bis‐Alkynyl‐Functionalized N‐Heterocyclic Carbenes: Reactivity, Photophysical Properties, and Quantum Chemical Investigations

“…Calculated excitationspectraofc omplexes 11 (black line, top) and 12 (black line, bottom) as well as spectraofr espective compounds in which the phenylalkynyl moieties of the NHC Di-Ph-Alkyne ligandsw ere replaced by methyl groups (red lines). comes brighter at temperatures below about 100 K. As imilar general trend as in previous work [28] was observed:c ompounds withouti ntra-and intermolecular (in the solid state) metallophilic interactions show relativelys imple PL spectra, whereas those of polynuclear compounds with pronounced metallophilic interactions are often complicated, in particular at low temperatures. The characteroft he peaks was visualized by using the unrelaxed differenced ensities.…”

“…[1][2][3][4][5][6][7][8][9][10] Nowadays, NHCs are considered to be maturel igands and are widely used in transition metal and main group chemistry. [13][14][15][16] In this way,f urtherd onor sites such as phosphines, [17][18][19][20][21] alcohols, [22][23][24][25] thiols, [26,27] and other functional groups [28][29][30] can be combined with NHC chemistry and allow ab road variety of applicationsf or functionalized NHC complexes. [13][14][15][16] In this way,f urtherd onor sites such as phosphines, [17][18][19][20][21] alcohols, [22][23][24][25] thiols, [26,27] and other functional groups [28][29][30] can be combined with NHC chemistry and allow ab road variety of applicationsf or functionalized NHC complexes.…”

“…[43][44][45] Nowadays,s imilar attractive intermetallic interactions are also known foro ther metal ions with d 10 configuration, for example, silver [46] and mercury. [20] As it is knownt hat coinagem etal ions also coordinate to alkynes, [28,[54][55][56] we thought that ac ombinationo fN HC ligands with alkynyl sidec hains should facilitate the formation of oli-gomeric metal compounds. For instance, there is still little understanding of how Au-Au contacts participate in certain catalytic steps.…”

“…[11,12] Besides their different steric ande lectronic properties compared to, for example, phosphines, NHCs are easily functionalized, as almosta ny organic substituent can be attached to the nitrogen atoms. [13][14][15][16] In this way,f urtherd onor sites such as phosphines, [17][18][19][20][21] alcohols, [22][23][24][25] thiols, [26,27] and other functional groups [28][29][30] can be combined with NHC chemistry and allow ab road variety of applicationsf or functionalized NHC complexes. Besides their applicationi nc atalysis, coinage metal compounds have also been extensively investigatedw ith respect to their photoluminescence properties.…”

Double‐Strand DNA Breaks Induced by Paracyclophane Gold(I) Complexes

“…Since these groundbreaking results, the research on gold complexes and their application in hetero‐ and homogeneous catalysis has experienced a significant upturn and can still be considered as one of the most up to date topics in organometallic chemistry . Besides their application in certain catalytic transformations, gold complexes have been thoroughly investigated in terms of their photophysical and cytotoxic properties . Since certain gold compounds are commercially available as antirheumatic agents (e.g., Auranofin/Ridaura © ), much effort has been made to investigate whether other gold complexes or gold nanoparticles might be useful as drug for some diseases, such as cancer or arthritis .…”