title: Preparation and properties of the full series of cuboidal clusters [Mo(x)W4-xSe4(H2O)12]n+ (n = 4-6) and their derivatives.
abstract: Hydrothermal reactions between incomplete cuboidal cluster aqua complexes [M3Q4(H2O)9]4+ and M(CO)6 (M = Mo, W; Q = S, Se) offer easy access to the corresponding cuboidal clusters M4Q4. The complete series of homometal and mixed Mo/W clusters [Mo(x)W4-xQ4(H2O)12]n+ (x = 0-4, n = 4-6) has been prepared. Upon oxidation of the mixed-metal clusters, it is the W atom which is lost, allowing selective preparation of new trinuclear clusters [Mo2WSe4(H2O)9]4+ and [MoW2Se4(H2O)9]4+. The aqua complexes were converted by ligand exchange reactions into dithiophosphato and thiocyanato complexes, and crystal structures of [W4S4((EtO)2PS2)6], [MoW3S4((EtO)2PS2)6], [Mo4Se4((EtO)2PS2)6], [W4Se4((i-PrO)2PS2)6], and (NH4)6[W4Se4(NCS)12]-4H20 were determined. Cyclic voltammetry was performed on [Mo(x)W4-xCO4(H2O)12]n+, showing reversible redox waves 6+/5+ and 5+/4+. The lower oxidation states are more difficult to access as the number of W atoms increases. The [Mo2WSe4(H2O)9]4+ and [MoW2Se4(H2O)9]4+ species were derivatized into [Mo2WSe4(acac)3(py)3]+ and [MoW2Se4(acac)3(py)3]+, which were also studied by CV. When appropriate, the products were also characterized by FAB-MS and NMR (31P, 1H) data.
authors.affiliation: A V Nikolayev Institute of Inorganic Chemistry, Novosibirsk 630090, Russia. caesar@che.nsk.su
authors.forename: M
authors.initials: M
authors.lastname: Sokolov
authors.forename: P
authors.initials: P
authors.lastname: Esparza
authors.forename: R
authors.initials: R
authors.lastname: Hernandez-Molina
authors.forename: J G
authors.initials: JG
authors.lastname: Platas
authors.forename: A
authors.initials: A
authors.lastname: Mederos
authors.forename: J A
authors.initials: JA
authors.lastname: Gavin
authors.forename: R
authors.initials: R
authors.lastname: Llusar
authors.forename: C
authors.initials: C
authors.lastname: Vicent