Dimensional reduction: Directed synthesis of metal-anion frameworks and heterometallic clusters

The work presented herein describes a predictive reaction scheme for solid state chemistry, dubbed dimensional reduction, and the extension of this method to the synthesis of heterometallic clusters.; In Chapter 2, the premises of dimensional reduction are set forth, specifying which aspects of a given reaction are predictable and the variation possible within those confines. Analysis of over 3000 known metal-halide, -oxide, and -chalcogenide frameworks demonstrates its general applicability. Examination of the data collected reveals underlying factors that affect whether a given system will obey the tenets of dimensional reduction, permitting enumeration of systems likely to be manipulated by this method and the probable products of such syntheses.; The concepts of dimensional reduction are extended further to describe the synthesis of heterometallic clusters in Chapter 3. The extended solid Re₄OS₂Se₈Cl₄ is presented, as are compounds containing discrete, soluble clusters of the type [Re_{6− n}Os_nSe ₈Cl₆](4−n )− (n = 1, 2, 3). Reaction with triethylphosphine yields [Re_6−nOs _nSe₈(PEt₃)₆](2+ n)+ (n = 1, 2), which, unlike previously known clusters of this type, exhibit reversible reduction waves in cyclic voltammetry measurements. Such reactions also reveal a glimpse of the differential reactivity possible with distinct metal sites, as the relatively facile removal of chloride ligands from osmium atoms permits isolation of trans,trans-[Re₄OS₂Se₈Cl ₄(PEt₃)₂].; Chapter 4 reports the syntheses of the hexacyanide clusters [Re _6−nOs_nSe ₈(CN)₆](4−n )− (n = 1, 2). The possibility of incorporating such clusters into porous solids is demonstrated through synthesis of Ni ₃[Re₅OsSe₈(CN)₆]₂·32H ₂O. The reduced clusters [Re_6−nOs _nSe₈(CN)₆](5− n)− (n = 1, 2) are described, suggesting the possibility of building a magnetically-ordered, porous framework. The potential for magnetic ordering is shown by the soluble assemblies {lcub}Re_6−nOs _nSe₈[CNCu(Me₆tren)]₆{rcub}(CF ₃SO₃)₉ (n = 0, 1, 2). The variable temperature magnetic properties of these clusters are reported, and indicate no magnetic coupling for the assemblies with oxidized (n = 0) or native (n = 1) central clusters, and weak ferromagnetic coupling for the assembly with a reduced central cluster (n = 2).; Chapter 5 concludes with the description of a new oxo-bridged dicluster {lcub}[Re₄Os₂Se₈(CN)₅]₂O{rcub} 4−. Strong coupling across the oxo-bridge is evident in the reduced form, {lcub}[Re₄Os₂Se₈(CN)₅] ₂O{rcub}5−.