TY - JOUR

T1 - Molecular Architecture of Poly nuclear Ruthenium Bipyridyl Complexes with Controlled Metal Helicity

AU - Fletcher, Nicholas C.

AU - Keene, F. Richard

AU - Viebrock, Heiko

AU - Von Zelewsky, Alex

PY - 1997/3/1

Y1 - 1997/3/1

N2 - The synthesis of di- and trinuclear ruthenium(II) complexes is reported, where each metal center has a tris-(bidentate) octahedral coordination sphere with predetermined stereochemistry. New members of the "Chiragen" ligand series, consisting of two linked chiral 4,5-pineno-2,2′-bipyridine groups, have been prepared, with small spacer units between the coordination centers (-(CH2)n {n= 0, 3} and -CH2(bpy)CH2-). X-ray structural data were obtained for the ligand Chiragen[3]. (Crystal data: orthorhombic, space group P212121, a = 12.229(1) Å, b = 12.790(1) Å, c = 20.215(1) Å, V = 3161.8(4) Å3, Z = 4.) Combination of the ligands with Ru(bpy)2Cl2 (where bpy is 2,2′-bipyridine) led to a mixture of diastereomers, while the use of enantiomerically pure Δ- or A-[Ru(bpy)2(py)2](dibenzoyltartrate) or Δ-Ru(CG[w-xyl])Cl2 led to almost complete stereoselectivity in the products. Circular dichroism spectra show that the complexes are composed of one helical diastereomer, with the expected absolute configuration predetermined by the chiral building block used. Additionally, 1H-NMR spectroscopy indicates C2 point group symmetry for the structures in solution, confirming the absence of ΔΔ diastereomers.

AB - The synthesis of di- and trinuclear ruthenium(II) complexes is reported, where each metal center has a tris-(bidentate) octahedral coordination sphere with predetermined stereochemistry. New members of the "Chiragen" ligand series, consisting of two linked chiral 4,5-pineno-2,2′-bipyridine groups, have been prepared, with small spacer units between the coordination centers (-(CH2)n {n= 0, 3} and -CH2(bpy)CH2-). X-ray structural data were obtained for the ligand Chiragen[3]. (Crystal data: orthorhombic, space group P212121, a = 12.229(1) Å, b = 12.790(1) Å, c = 20.215(1) Å, V = 3161.8(4) Å3, Z = 4.) Combination of the ligands with Ru(bpy)2Cl2 (where bpy is 2,2′-bipyridine) led to a mixture of diastereomers, while the use of enantiomerically pure Δ- or A-[Ru(bpy)2(py)2](dibenzoyltartrate) or Δ-Ru(CG[w-xyl])Cl2 led to almost complete stereoselectivity in the products. Circular dichroism spectra show that the complexes are composed of one helical diastereomer, with the expected absolute configuration predetermined by the chiral building block used. Additionally, 1H-NMR spectroscopy indicates C2 point group symmetry for the structures in solution, confirming the absence of ΔΔ diastereomers.

U2 - 10.1021/ic960948n

DO - 10.1021/ic960948n

M3 - Journal article

AN - SCOPUS:0001572023

VL - 36

SP - 1113

EP - 1121

JO - Inorganic Chemistry

JF - Inorganic Chemistry

SN - 0020-1669

IS - 6

ER -