Crystal and molecular structure of µ-trimethylsilylcycloheptatrienylpentacarbonyltrimethylsilyldiruthenium(Ru–Ru): a binuclear metal complex with a bridging cycloheptatrienyl ligand

Abstract

Crystals of the title compound are orthorhombic. space group P2₁2₁2₁, with Z= 4 in a unit cell of dimensions: a= 10·355(2), b= 12·380(5), c= 17·580(5)Å. The structure was determined by direct methods from diffractometer data and refined to R 0·049 for 2024 independent reflections. The two ruthenium atoms are bonded to one another [Ru–Ru 2·937(2)Å] and to the cycloheptatrienyl ring; four of the carbon ring atoms effectively comprise a diene system bonded (somewhat asymmetrically) to Ru(1), while the other three carbon atoms form an allyl group bonded to Ru(2). The interplanar angle between the diene and allyl fragments is 57°. The central chain of the molecule comprises the sequence OC–Ru–Ru–SiMe₃; the O–C–Ru–Ru chain is almost linear, but the silyl group is bent away from the C₇ ring to give Ru–Ru–Si 173°[Ru–Si 2·456(4)Å]. The two equatorial carbonyl groups on each Ru atom are approximately orthogonal to one another and are in an eclipsed configuration.