27829-16-9Relevant academic research and scientific papers
Chiral discrimination in the reduction of [Co(edta)]- by [Co(en)3]2+ and [Ru(en)3]2+. X-ray structure of [Λ-Co(en)3][Δ-Co(edta)]2Cl·10H 2O
Warren, Robert M. L.,Haller, Kenneth J.,Tatehata, Akira,Lappin, A. Graham
, p. 227 - 232 (2008/10/08)
The structure of the salt [Λ-Co(en)3][Δ-Co(edta)]2Cl·10H 2O has been determined by X-ray crystallography. The salt crystallizes in the orthorhombic space group P21212 (No. 18) with Z = 2, a = 21.046(3) A?, b = 12.813(2) A?, c = 8.158(1) A?, and R = 0.035 for 5263 reflections. The complex ions participate in a network of hydrogen bonds which is interpreted to suggest a mechanism for chiral discrimination. Outer-sphere reduction of [Co(edta)]- by [Ru(en)3]2+ takes place with a second-order rate constant of 6 × 103 M-1 s-1 at 25°C and 0.10 M ionic strength. Chiral induction in the reaction results in a 2% enantiomeric excess with a ΔΛ preference, significantly smaller than the 10% ΔΛ induction found with [Co(en)3]2+ as reductant. This difference in chiral induction between the two reductants is ascribed to differences in chiral recognition in the assembly of electron-transfer precursor complexes.
