title: Adamantane-like cluster complexes of mixed-valent copper-copper and nickel-copper thiolates.
abstract: Square-planar copper(II) and nickel(II) derivatives of the cis-dithiolate N(2)S(2) ligand bis(N,N'-2-mercapto-2-methylpropyl)-1,5-diazocyclooctane, (bme*daco)M, nucleate four Cu(I)Cl moieties, forming M(II)(2)Cu(I)(4)S(4) clusters with unusual triply bridging thiolates, mu(3)-SR, in the topological form of adamantane. As determined by X-ray crystallography, the (bme*daco)M (M = Cu or Ni) metallothiolate serves as a bidentate ligand that bridges four Cu(I) ions, utilizing all lone pairs on sulfurs. Further characterization by electrochemical and electronic spectral measurements suggests greater electron delocalization in the all-copper complex as compared to the NiCu heterometallic complex. Mass spectral data imply that the mixed-metal Ni(II)(2)Cu(I)(4)S(4) is more stable toward CuCl loss than Cu(II)(2)Cu(I)(4)S(4), a result that is corroborated by extraction of Cu(I) by 1,2-bis(diphenylphosphino)ethane in the latter but not the former.
authors.affiliation: Department of Chemistry, Texas A&M University, College Station, TX 77845, USA.
authors.forename: Matthew L
authors.initials: ML
authors.lastname: Miller
authors.forename: Said A
authors.initials: SA
authors.lastname: Ibrahim
authors.forename: Melissa L
authors.initials: ML
authors.lastname: Golden
authors.forename: Marcetta Y
authors.initials: MY
authors.lastname: Darensbourg