Crystal and molecular structure of tri-µ-(dimethylgermanio)-tris(tricarbonylruthenium), [Ru(CO)3(GeMe2)]3

Abstract

Crystals of [Ru(CO)₃(GeMe₂)]₃ are hexagonal, space group P6₃/m, with Z= 2 molecules in a unit cell of dimensions a= 10·92, c= 12·18 Å. The structure was refined to R 0·072 for 137 independent reflections. The three germanium atoms are coplanar with the three ruthenium atoms which form an equilateral triangle of side 2·93(1)Å. Two of the carbonyl groups on each Ru atom are mutually trans and almost perpendicular to the Ru₃Ge₃ plane, while the third lies equatorially along the mirror line of the Ru₃ triangle. The Me₂Ge bridges are symmetrical, with a Ru–Ge distance of 2·49(1)Å and an angle of 71·9(3)°. The molecule possesses idealised symmetry D_3h(m2), and is the first example to be definitively established of a six-membered heterocyclic metal ring system.