94249-62-4Relevant academic research and scientific papers
Chiral octahedral iron and ruthenium complexes. Use of diastereotopic phosphorus atoms for the direct observation of hidden coupling constants
Pa?kowski, Marek,Chodkiewicz, Wladyslaw,Simonnin, Marie-Paule
, p. 533 - 541 (2008/10/08)
A series of asymmetric phosphorus ligands was synthesized and used to prepare chiral octahedral iron and ruthenium complexes (MR(CO)2L*(PMe3)2)+A -. Their geometrical configuration was deduced from IR and NMR (1H, 31P) spectroscopic studies. Due to the presence of an asymmetric center directly bonded to the metal atom, the two axial PMe3 ligands are shown to be diastereotopic and this allows, for the first time, a direct determination of the phosphorus-phosphorus coupling constants between chemically identical ligands by 31P NMR. The conformation of the asymmetric ligands relative to the other ligands, CO, R, and the two axial PMe3 groups, is shown to be an important factor in determining the magnitude of the proton inequivalence between the two PMe3 ligands.
