Terminal Coordination of a Gallium(I) Species to a Transition Metal. Syntheses and Crystal Structures of Ru{GaCl(THF)2}{GaCl2(THF)}2(CO)3·0.5THF and Ru2{GaCl2(THF)}2(CO)8

The reaction of Ru3(CO)12 with Ga2Cl4 in the presence of gallium metal in refluxing toluene, followed by crystallization from tetrahydrofuran, produces Ru{GaCl(THF)2}{GaCl2(THF)}2(CO)3·0.5 THF (1) and Ru2{GaCl2(THF)}2(CO)8 (2) (THF = tetrahydrofuran). The ruthenium atom in 1 has an approximately octahedral coordination environment, with meridinal arrangements of carbonyl ligands and gallium atoms. The GaCl(THF)2 group is in a position trans to one of the GaCl2(THF) groups. The crystal structure of 2 consists of a linear arrangement of metal atoms in which two GaCl2(THF) groups are in axial positions with respect to the metal−metal bond of an Ru2(CO)8 unit. Crystal data for 1: monoclinic space group P21/c (No. 14), a = 17.367(3) Å, b = 12.054(2) Å, c = 16.049(3) Å, β = 95.18(1)°, Z = 4, R = 0.0527, R w = 0.0718. Crystal data for 2: monoclinic space group P21/c (No. 14), a = 11.980(1) Å, b = 6.944(1) Å, c = 16.097(3) Å, β = 96.81(1)°, Z = 2, R = 0.0300, R w = 0.0510. The title complexes are the first compounds to contain ruthenium−gallium bonds, and compound 1 is the second structurally-characterized example of a complex in which a gallium(I) species is terminally coordinated to a transition metal.