ALKENE ANALOGUES OF BIS(N-DONOR)KETONE LIGANDS - RUTHENIUM(II) COMPLEXES CONTAINING 1-(PYRIDIN-2-YL)-1-(N-METHYLIMIDAZOL-2-YL)ETHENE AND 1,1-BIS(N-METHYLIMIDAZOL-2-YL)ETHENE((MIM)(2)C=CH2), AND STRUCTURAL STUDIES OF [RU(BPY)(2)((MIM)(2)C=CH2)][PF6](2

摘要

The complexes [Ru(bpy)(2)(N similar to N)][PF6](2) have been synthesized from reactions of cis-[RuCl2(bpy)(2)]. 2H(2)O (bPY=2,2'-bipyridine) and the bidentate ligands N similar to N ((mim)(2)C=CH2 and (py)(mim)C=CH2 where py=pyridin-2-yl and mim=N-methylimidazol-2-yl) in aqueous ethanol; with the analogue (py)(mim)C=O, the pyridine-2-carboxylate complex [Ru(bpy)(2)(pyCO(2))][PF6] is formed. The complexes [Ru(bpy)(2){(mim)(2)C=CH2}][PF6](2) (1) and [Ru(bpy)(2)(pyCO(2))][PF6] (3), characterized by room-temperature single crystal X-ray studies, were shown to have distorted octahedral geometry for ruthenium(II). The (mim)(2)C=CH2 ligand is non-planar, with the mim mean planes forming a dihedral angle of 32.2(1)degrees and forming dihedral angles of 56.5(1) and 60.4(1)degrees with the 'C=CC2' mean plane, in contrast to the near planarity reported for the ketone analogue (mim)(2)C=O in other metal complexes. Crystallographic data: for 1, monoclinic, space group C2/c, a=25.123(9), b=13.607(1), c=21.310(1) Angstrom, beta=103.61(4)degrees, Z=8, R=0.040 for N-o=6065 'observed' reflections, R(w)=0.041; for 3, monoclinic, space group P2(1)/c, a=14.463(10), b=11.211(7), c=18.619(13) Angstrom, beta=119.97(6)degrees, Z=4, R=0.045 for N-o=3031 'observed' reflections, R(w)=0.048. [References: 43]