Synthesis and structure of the cationic tert-butoxide complexes Y3(OR)7Cl(THF)3+, Y2(OR)4Cl(THF)4+, and Y(OR)Cl(THF)5+: representatives of a new class of yttrium alkoxides

Y{sub 3}(OR){sub 7}Cl{sub 2}(THF){sub 2} (1) (R = CMe{sub 3}) reacts with AgBPh{sub 4} to form a mixture of (Y{sub 3}({mu}{sub 3}-OR)({mu}{sub 3}-Cl)({mu}-OR){sub 3}(OR){sub 3}(THF){sub 3})(BPh{sub 4}) (2) and (Y{sub 2}({mu}-Cl)({mu}-OR){sub 2}(OR){sub 2}(THF){sub 4})(BPh{sub 4}) (3). At 0{degree}C the reaction favors 2, which can be isolated by crystallization from toluene at {minus}37{degree}C. 2 forms crystals in space group P{anti 1} (C{sub i}{sup l}; No. 2) with a = 14.131 (3) {angstrom}, b = 15.035 (3) {angstrom}, c = 18.712 (5) {angstrom}, {alpha} = 85.01 (2){degree}, {beta} = 85.02 (2){degree}, {gamma} = 81.75 (2){degree}, V = 3,908 (2) {angstrom}{sup 3}, and D{sub calcd} = 1.23 g cm{sup {minus}3} for Z = 2. Least-squares refinement of the model based on 4,692 reflections converged to a final R{sub F} = 9.1%. The three yttrium atoms in 2 form an equilateral triangle with doubly bridging alkoxide groups along the edges and triply bridging alkoxide and chloride ligands above and below the plane of metals.