Dichlorido(furfurylamine-κN)(η6-hexamethylbenzene)ruthenium(II)

The single-crystal X-ray structure analysis of [RuCl2(C12H18)(C5H7NO)] reveals a distorted piano-stool geometry around the RuII atom, with a hexamethylbenzene ligand, two chloride ligands and a furfurylamine ligand, the latter coordinating through the amine group. In the crystal, a dimeric structure is observed as a result of N—H⋯Cl interactions between two symmetry-related molecules.

The single-crystal X-ray structure analysis of [RuCl 2 (C 12 H 18 )-(C 5 H 7 NO)] reveals a distorted piano-stool geometry around the Ru II atom, with a hexamethylbenzene ligand, two chloride ligands and a furfurylamine ligand, the latter coordinating through the amine group. In the crystal, a dimeric structure is observed as a result of N-HÁ Á ÁCl interactions between two symmetry-related molecules.
AG gratefully acknowledges financial support from the Federal Commission for Scholarships for Foreign Students.
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: FF2034).
The formation of (η 6 -C 12 H 18 )RuCl 2 (C 5 H 7 NO-κN) is easily monitored by 1 H NMR spectroscopy, in which the signal corresponding to the protons of the NH 2 group is strongly shifted by 1.57 p.p.m., while the signal of the CH 2 protons is also shifted downfield but to a lesser extent (0.15 p.p.m.) as compared to uncoordinated furfurylamine. The infrared spectrum of (η 6 -C 12 H 18 )RuCl 2 (C 5 H 7 NO-κN) shows as well shifting of some of the bands associated to the furfurylamine moiety, especially those corresponding to the symmetrical and asymmetrical ν NH , in accordance with other metal complexes of furfurylamine derivatives (Joesten et al., 1967). In addition, the molecular structure of the complex has been established by single-crystal structure analysis.
The title complex shows a three-legged piano-stool geometry with the Ru II metal center being surrounded by an hexamethylbenzene ligand, two terminal chlorido and a N-coordinated furfurylamine ligand, see Fig. 1. The furfurylamine acts as a monodentate ligand and the Ru-N distance at 2.156 (2) Å is comparable to the one found in the analogous dichlorido(η 6 -p-cymene)(benzylamine-κN)ruthenium(II) complex [2.1445 (18) Å] (Govindaswamy et al., 2004). The aromatic ring of the hexamethylbenzene is planar and the Ru-centroid distance is 1.672 Å (centroid defined by C6 to C11). Otherwise, the Ru-Cl distances are almost equivalent at 2.4277 (9) and 2.4299 (8) Å, respectively, which is similar to those found in other dichlorido arene ruthenium complexes (Therrien & Süss-Fink, 2004;Govindaswamy et al., 2004;. In the crystal packing, one chlorido is involved in an H-bonded interaction with the NH 2 moiety of a neighbouring molecule, thus forming a centrosymmetric dimeric structure: The N-Cl separations being 3.406 (3)Å with the N-H···Cl angles being 168.3°.

Experimental
Furfurylamine was purchased from Aldrich and used as received and [(η 6 -C 12 H 18 )Ru(µ-Cl)Cl] 2 (Bennett et al., 1982) was prepared according to published methods. The NMR spectrum was recorded on a Bruker 400 MHz spectrometer. The infrared spectrum was recorded on a Perkin-Elmer 1720X FT-IR spectrometer (4000-400 cm -1 ).