57255-56-8Relevant academic research and scientific papers
1H NMR spectra of ternary platinum(II) complexes with N-ethyl- or N- benzyl-1,2-ethanediamine and 2,2'-bipyridine or 1,10-phenanthroline: Intramolecular aromatic-aromatic interaction in coordination sphere, and it's solvent and temperature effects
Goto, Masafumi,Sumimoto, Masamitsu,Matsumoto, Takashi,Iwasaki, Maki,Tanaka, Yoshitomo,Kurosaki, Hiromasa,Yuto, Koji,Yoshikawa, Yuzo
, p. 1589 - 1598 (2007/10/03)
Square-planar complexes with the formula [Pt(L1) (L2)]X2, where L1 is di(ammine) or 2,2'-bipyridine (bpy) or 1,10-phenanthroline (phen) and L2 is N-ethyl-1,2-ethanediamine (Eten) or N-benzyl-1,2-ethanediamine (Been), and X = NO3- or Cl-, were prepared. NMR measurements of D2O solutions of these complexes showed that the N-ethyl and N-benzyl groups are forced to take a pseudo axial disposition due to an intramolecular repulsion from hydrogen atoms of aromatic diamines for complexes where L1 = bpy or phen and significant upfield shifts due to the ring current effect were observed for the Been complexes. An analysis of coupling with N-H and 195Pt showed that the major rotamer due to rotation around CH2-NH is (-)-syn for the Been with a significant intramolecular stacking between aromatic rings of L1 and L2, but anti-for the Eten complexes. The solvent and temperature dependency of the upfield shift of the Been complexes are described; the protein denaturants, guanidinium chloride, and urea, act to reduce stacking as dioxane.
