Synthetic and structural studies on the formation of a tetradecametallic yttrium oxide alkoxide chloride complex: An example of how molecular yttrium oxygen frameworks from extended arrays

YCl3 reacts with 2 equiv of NaOCMe3in THF to from Y3(OCMe3)7Cl2(THF)2 (1) in 80% yield. The yttrium atoms in this molecule form a triangle that has double bridging alkoxide groups along each edge, a μ3-OCMe3 group on one side of the Y3 plane, and a μ3-Cl ligand on the other side. One metal is coordinated to a terminal chloride ion and a terminal alkoxide group. Each of the other metals is coordinated to a terminal alkoxide group and a molecular of THF. Both chloride ions lie on the same side of the Y3 plane as the two THF ligands. In toluene under nitrogen over a period of 2 weeks, 1 converts to Y14-(OCMe3)28Cl10O2(THF)4 (2) in quantitative yield. 2 is comprised of four trimetallic Y3(μ3-OR)(μ3-X)(μ-Z)3 units (where X = Cl, O; Z = Cl, OCMe3) that have structures similar to the Y3(μ-OR)(μ3-Cl)(μ-OR)3(OR)3Cl(THF)2 structure of 1. The four trimetallic subunits in 2 are connected by two μ-Cl ions, a μ4-O ion and a [(μ-OR)2Y(μ-Cl)]2 group. Complex 2 is a dimer, [[Y3(μ3-OR)(μ3-Cl)(μ-OR)3(OR)3(THF)2](μ-Cl)[Y3(μ3-OR)(μ-OR)2(μ-Cl)(OR)2](μ4-O)[(μ-OR)2Y(μ-Cl)]]2, which contains a center of inversion. The crystal structures of 1 and 2 are reported. 52 refs., 3 figs., 3 tabs