Synthesis of Cyclometalated Palladium(II) and Platinum(II) Complexes Using 2-Substituted 8-Quinolinols Containing C-Donor Atoms and Steric Interaction between the Ligands

Shinichi OHFUCHI*, Chitoshi KITAMURA†, George R. NEWKOME†† and Akio YONEDA†

Department of Applied Chemistry, Kobe City College of Technology; 8-3, Gakuenhigashi-machi, Nishi-ku, Kobe-shi 651-2194 Japan
† Department of Applied Chemistry, Faculty of Engineering, Himeji Institute of Technology; 2167 Shosha, Himeji-shi 671-2201 Japan
†† Department of VP Research & Grad School, The University of Akron; Akron, OH 44325-4717 U.S.A.

Cyclometalated complexes of 2-substituted 8-quinolinols possessing two or three carbon side chains have been prepared in the presence of a second ligand. The 5,5- or 5,6-chelate ring system containing a Pd (II)- or Pt (II)-C (sp3) bond is very stable. There are notable steric interactions among three adjacent substituents. The X-ray structure analysis of the complex containing a bulky second ligand, such as PPh3, reveals a remarkable distortion within the Pd-coordination plane. The steric repulsion was observed also in solution by 1H-NMR spectroscopy. A novel cyclometalated palladium complex of 3'-azido- 3'-deoxythymidine (AZT) was prepared and the steric interaction was investigated by H-H COSY analysis.


[Contents (In Japanese) ] [Contents (In English) ]