T. Suzuki et al., Syntheses and structures of novel zerovalent 2,2 '-bipyridyl or 1,10-phenanthroline ruthenium complexes, ORGANOMETAL, 18(18), 1999, pp. 3671-3678
Rut 1-6-eta-cyclooctatriene)(eta(2)-dimethyl fumarate)(2) (2), which is eas
ily derived from Ru(1-2:5-6-eta-cyclooctadiene)( 1-6-eta-cyclooctatriene) (
1), reacts with bidentate nitrogen ligands, 2,2'-bipyridyl or 1,10-phenanth
roline, to give novel ruthenium(0) complexes, Ru(1-2:5-6-eta-cyclooctatrien
e)(eta(2)-dimethyl fumarate)(N N)(N N = 2,2'-bipyridyl (3a) or 1,10-phenant
hroline (3b)) quantitatively. On the other hand, the complex 1 reacts with
dimethyl fumarate in the presence of N N to give novel ruthenium(0) complex
es, Ru(1-2:5-6-eta-cyclooctadiene)(eta(2)-dimethyl fumarate)(N N) (N N = 2,
2'-bipyridyl (4a) or 1,10-phenanthroline (4b)), in high yields. The structu
res of the complexes 3a, 3b, and 4b were established. by X-ray analyses, an
d the coordination geometry around the central ruthenium atom in these comp
lexes was a distorted trigonal bipyramid. The two nitrogen atoms occupy an
axial and an equatorial position, respectively, the two olefinic moieties o
f the cyclooctatriene or cyclooctadiene occupy an axial and an equatorial p
osition, respectively, and the dimethyl fumarate was coordinated in the equ
atorial plane.