Zwitterionic Metalates of Group 11 Elements and Their Use as Metalloligands for the Assembly of Multizwitterionic Clusters

Abstract

Reaction of RNHC(S)PPh2NPPh2C(S)NR (HRSNS; R = Me, Et) with M(I) (M = Cu, Ag, Au) salts afforded zwitterionic complexes of the general formula [M(RSNS)] (M = Cu, Ag, Au). The ligand was found in the solid state in S,S-kappa2 and S,N,S-kappa3 coordination fashions. [Cu(RSNS)] and [Ag(RSNS)] can be used as metalloligand building blocks for the assembly of pentanuclear multizwitterionic Cu5, Cu3Ag2 and Ag5 core clusters of the general formula [M'2{M(RSNS)}3]2+ (M = Cu, M' = Cu, Ag; M = M' = Ag) upon reaction with suitable M' salts. The crystal structures of the most significant compounds are reported herein. Compound [Ag2{Ag(RSNS)}2(OTf)2] was also isolated and structurally characterized, representing a model for the intermediate species of the aforementioned assembly.

Temperature‐Dependent Fluorescence of Cu5 Metal Clusters: A Molecular Thermometer

“…[13,14] Its absorption spectrum presents a broad and unstructured band below 450 nm (Figure 2 A). The system is luminescent in all phases, both at room temperature and at 77 K (Figure 2 B) and no dependence on the solvent was observed.…”

A Study on the Coordinative Versatility of the Zwitterionic S,N,S Ligand EtNHC(S)­Ph2P=NPPh2C(S)NEt in Its Anionic, Neutral and Cationic Forms – Determination of Absolute pKa Values in CH2Cl2 of RhI Complexes

“…The distorted square-planar coordination is completed by a chelating cod molecule. The S1-Rh1-S2 angle of 92.90(2)°is dramatically narrower than that observed in the S,S-chelated complex [Au(EtSNS)], [2] in which the coordination over the metal center is almost linear [S1-Au1-S2 177.73(6)°]. An intermediate geometry [2] was found in dimer [Ag(EtSNS)] 2 [mean value of the S-Ag-S angles 136.6(1)°].…”

“…As previously reported, EtSNS -acts as an S,N,S-tridentate or S,S-bidentate ligand towards M I species (M = Rh [1] and Cu, Ag, Au [2] ), whose N atom, as evidenced by its bent geometry, may coordinate a metal center, although this behavior has never been observed. [3] We also became interested in studying the coordination properties of HEtSNS and H 2 EtSNS + .…”

“…The zwitterionic ligand EtNHC(S)Ph 2 P=NPPh 2 NEt (HEtSNS, Scheme 1) can be prepared in high yield by double addition of ethylisothiocyanate (EtNCS) to bis(diphenylphosphanyl)amine (Ph 2 PNHPPh 2 , dppa), [1,2] which forms one thioamidic and one thioamidyl functionality bound to the phosphorus atoms. The opposite charges are formally located on the zwitterionic thioamidyl-phosphonium, N -C(S)P + , functional group.…”

“…[3] We also became interested in studying the coordination properties of HEtSNS and H 2 EtSNS + . Their reactivity towards Rh I species derived from [Rh(CO) 2 Cl] 2 and [Rh(cod)Cl] 2 (cod = 1,5 cyclooctadiene) is reported. Acid-base properties of the [Rh-(CO)(EtSNS)] complex are discussed together with a general method for the determination of absolute pK a values in dichloromethane.…”