Acylchalcogenourea Complexes of Silver(I)

Abstract

Acylthio- or acylselenoureas react with silver(I) oxide to form tetranuclear silver(I) complexes containing the deprotonated acylchalcogenourea ligands bound to the silver atoms through the chalcogen and oxygen atoms. These tetrasilver(I) species react with either 4 or 8 equiv. of a phosphine to afford either dinuclear silver(I) phosphine complexes or tetrahedral silver diphosphine complexes. In these compounds, the acylchalcogenourea ligands form six-membered rings by coordinating to the metal atom through the chalcogen and oxygen atoms. In one case, we observed a very rare example of an acylthiourealigand coordinated through the nitrogen and sulfur atoms to form a four-membered ring. A silver(I) complex containing adeprotonated acylselenourea and an N-heterocyclic carbene ligand is also reported. This was prepared from the corresponding acetate derivative and the acylselenourea; in this case, the acetate acts as the base. All of the reported compounds were characterized by spectroscopic techniques, and many were also studied by single-crystal X-ray diffraction

Acylseleno- and acylthioureato complexes of gold(i) N-heterocyclic carbenes

“…Initially, we examined three different routes towards the desired NHC-gold(I) acylchalcogenoureato complexes: (1) the reaction of the acylchalcogenoureas with [AuCl(IPr)] [IPr = 1,3-di(2,6diisopropylphenyl)imidazolylidene] in the presence of base, (2) the reaction of the acylchalcogenoureas with [AuOH(IPr)] and (3) by transmetallation of [AuCl(IPr)] with the corresponding silver(I) acylchalcogenoureato complexes. 17 To our surprise, the latter two routes afforded either no products at all or we observed formation of dark, inseparable mixtures. In particular, the lack of reactivity of the gold(I) hydroxy complex [AuOH(IPr)] in this system is somewhat unexpected.…”

“…We have previously reported the first Ag + and Au + compounds containing acylselenoureato and acylthioureato ligands together with a detailed study of their biological activity. [16][17][18][19] We also demonstrated that square planar gold(III) complexes with acylselenoureato ligands are accessible when a dicarbanionic co-ligand is present. 20 This stabilizing co-ligand is essential to prevent reduction of gold by the acylselenourea during the reaction.…”

Multifunctional Ag(I)/CAAA-Amidphos Complex-Catalyzed Asymmetric [3 + 2] Cycloaddition of α-Substituted Acrylamides

“…1d (Figure b–d). These results meant that the single peak might be derived from the higher aggregation state B of complex A . Subsequently, when iminoester 2a was added to the complex solution (a), (c) and (d), respectively, we found the two doublet peaks of the Ag- 1d (1:1) complex A was easily moved to a new position at 31.88 ppm compared with the single peak of aggregated form B (Figure e–g).…”

Acylselenoureas, selenosemicarbazones and selenocarbamate esters: Versatile ligands in coordination chemistry

“…7a). 80 These clusters react with four or eight equivalents of a phosphine affording dinuclear Ag 81 The presence of the co-ligands is essential in this case to stabilise the copper(I) oxidation state.…”