Homoleptic and heteroleptic Au(I) complexes containing the new [Co5C(CO)12](-) cluster as ligand.

Abstract

The new [{Co5C(CO)12}Au{Co(CO)4}](-), , cluster has been obtained from the reaction of [Co6C(CO)15](2-) with two equivalents of [AuCl4](-). reacts with an excess of HBF4 resulting in the formation of [{Co5C(CO)12}2Au](-), . The new derivatives [Co5C(CO)12(AuPPh3)], , and [Co5C(CO)11(AuPPh3)3], , have been obtained by reacting with two and four equivalents of [Au(PPh3)Cl], respectively. All the new species have been structurally characterised by means of X-ray crystallography as their [NEt4][], [NEt4][], [NMe3(CH2Ph)][], and thf·0.5C6H14 salts and solvates. may be viewed as a homoleptic Au(i) complex containing two [Co5C(CO)12](-) clusters as ligands. Similarly, and are heteroleptic Au(i) complexes containing one [Co5C(CO)12](-) cluster ligand as well as [Co(CO)4](-) or PPh3. Conversely, contains the [Co5C(CO)11](3-) cluster stabilized by three [AuPPh3](+) fragments. and have been investigated in solution by means of electrochemical and spectroelectrochemical methods, revealing a very rich redox propensity to form the closely related (n = 1-3) and (n = 0-3) species.