Preparation and Solution Properties of Chalcogenide-Rich Clusters [Mo(3)Y(7)(H(2)O)(6)](4+) (Y = S, Se): Kinetics of PR(3)(3-) Abstraction of Y from &mgr;-(Y(2)(2-)) and H(2)O Substitution by Cl(-) and Br(-).

The chalcogenide-rich trinuclear Mo(IV)(3) clusters [Mo(3)Y(7)(H(2)O)(6)](4+), containing single &mgr;(3)-(Y(2)(-)) and three &mgr;-(Y(2)(2)(-)) core ligands, have been obtained for the first time from polymeric {Mo(3)Y(7)Br(4)}(x)() via [Mo(3)Y(7)Br(6)](2)(-) (Y = S, Se). ICP analyses of 2 M HCl solutions give Mo:S and Mo:Se ratios consistent with the formulas indicated, and on reaction with concentrated HBr, 85% recovery of (Et(4)N)(2)[Mo(3)S(7)Br(6)], the structure of which is known, has been achieved. Abstraction of S and Se with PPh(3) (two-phase system), or the water-soluble phosphine (3-SO(3)C(6)H(4))(3)P(3)(-) (PR(3)(3)(-)), gives quantitative formation of [Mo(3)S(4)(H(2)O)(9)](4+) and [Mo(3)Se(4)(H(2)O)(9)](4+).

Aqueous Solution Chemistry of the Mo(3)PdS(4) Cube: Substitution Reactions and the Double to Single Cube Interconversion Induced by CO, Two Phosphines, Cl(-), Br(-), and NCS(-).

The kinetics of conversion of an edge-linked double cube, in this case [{Mo(3)PdS(4)(H(2)O)(9)}(2)](8+), to the corresponding single cube [Mo(3)(PdX)S(4)(H(2)O)(9)](4+), has been studied for the first time. Reaction is induced by six reagents X = CO, two water-soluble phosphines, Cl(-), Br(-), and NCS(-), which complex at the tetrahedral Pd. The first stage of reaction is fast and is accompanied by color changes, e.

Interconversion and Reactivity of Two Heterometallic Tin-Containing Cuboidal Clusters from [Mo(3)S(4)(H(2)O)(9)](4+): X-ray Structure of the Single Cube with an Mo(3)SnS(4) Core.

The Mo(3)SnS(4)(6+) single cube is obtained by direct addition of Sn(2+) to [Mo(3)S(4)(H(2)O)(9)](4+). UV-vis spectra of the product (0.13 mM) in 2.