Site-selective and stepwise complexation of two M(cod)+ (M = Rh, Ir) fragments with calix[4]arene.
The reaction of [(cod)M(mu-OMe)]2 (M = Rh, Ir; cod = cycloocta-1,5-diene) with calix[4]arenes (LH4) in the molar ratio of 0.5-0.6:1 gave the rhodium and iridium pi-arene complexes [(cod)M(eta 6-LH3)], while that in the molar ratio of 1.1-1.5:1 (M = Rh) led to the selective formation of the dinuclear complexes [((cod)Rh)2(eta 6:eta 2-LH2)] in which one of the Rh(cod)+ fragments is coordinated by an eta 6-aryl group and the other by two phenolic oxygen atoms; the stepwise synthesis of the Rh-Ir heterobimetallic analogue of the latter complex was further achieved.
Ishii
Youichi
Y
Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan. ishii@chembio.t.u-tokyo.ac.jp
Onaka
Ken-ichi
K
Hirakawa
Hidehiko
H
Shiramizu
Kohei
K