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Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
Synthesis, structure, and ferromagnetic behavior of decacopper(II) cluster complex supported by hexaanionic
Takashi Kajiwara1, Noriyoshi Kon, Shuichi Yokozawa
1Department of Chemistry, Graduate School of Science, Tohoku University, Aramaki Aoba-ku, Sendai 980-8578, Japan. kajiwara@agnus.chem.tohoku.ac.jp
Abstract:
A nanosized decacopper(II) cluster complex was synthesized using p-tert-butylthiacalix[6]arene as a ligand. In the complex, the calixarene assumes a "pinched cone" conformation and acts as an undecadentate ligand via six phenoxy oxygen and five sulfur atoms. The resulting pentacopper(II) subunits are connected by two hydroxo and two oxo groups to form decacappoer(II) cluster core. The core structure remains intact in alcoholic solution as shown by ESI MS. The temperature dependence of chimT clearly shows ferromagnetic behavior of the core due to orthogonality between two adjoining magnetic orbitals of copper(II) ions.
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