A versatile gold synthon for acetylene C–H bond activation

Abstract

The reaction of N,N'-bis(2,6-diisopropylphenyl)imidazol-2-ylidene gold hydroxide ([Au(OH)(IPr)]; 1) with acetylene and trimethylsilylacetylene derivatives cleanly leads to the formation of a gold-acetylide bond with the concomitant formation of water or trimethylsilanol. All compounds were isolated in high yield (>85%). The crystal structures of selected gold acetylides in conjunction with their UV-vis absorption/emission properties were investigated. Finally, DFT calculations were performed in an attempt to gain an insight into the mechanism of the general reaction.

Transmetalation between Au(I) and Sn(IV) complexes. The reaction mechanism in non-coordinating and coordinating polar solvents

“…The slight difference between Au-C1 and Au-C12 bond distances of 2.018(4) and 1.982(4) Å, respectively, can be accounted for the different hybridization of C1(sp 2 ) and C12(sp) atoms. These distances are similar to those observed in other alkynyl-carbene-gold(I) complexes [20][21][22][23][24]. The carbon-carbon bond length of 1.199(6) Å between C12 and C13 corresponds to a typical C"C triple bond in this class of complexes.…”

Tracking gold acetylides in gold(i)-catalyzed cycloisomerization reactions of enynes

“…The observation of these ions suggests the formation of gold acetylides, on which a second gold entity coordinates, thus creating gold dinuclear species. This was further corroborated by submitting the independently synthesized gold acetylide 1-Au 17,18 to A-C or AgSbF 6 , leading to the expected peaks of the corresponding dinuclear species. 19 The latter were next fragmented by Collision Induced Dissociation (CID), giving rise to cations bearing all of the phosphines.…”

Ligand Exchange at a Gold(I) Carbene Complex

“…These chemical shifts are significantly downfield from the C NHC resonance found for complex 1 (δ = 178.3 ppm) [43] nicely illustrating the dependence of the C NHC resonance on the co-ligand. The C NHC resonance of 2 falls in the range previously reported for a gold(I) NHC/acetylide complex [45,46]. The C NHC resonance of complex 3 cannot be compared to other Au I -NHC-SPh complexes due to lack of available 13 C NMR data.…”