TY - JOUR
T1 - Synthesis and characterization of imidazolate-bridged polynuclear copper complexes
AU - Higa, Takumi
AU - Moriya, Masaki
AU - Shimazaki, Yuichi
AU - Yajima, Tatsuo
AU - Tani, Fumito
AU - Karasawa, Satoru
AU - Nakano, Motohiro
AU - Naruta, Yoshinori
AU - Yamauchi, Osamu
N1 - Funding Information:
We gratefully acknowledge the support of this work by a Grant-in-Aid for Scientific Research (No. 17750055 to Y.S. and No. 16350036 to O.Y.) of the Ministry of Education, Culture, Sports, Science and Technology of Japan.
PY - 2007/7/2
Y1 - 2007/7/2
N2 - Copper(II) complexes of N4-donor ligands containing imidazole moieties, 4-[bis(1-methylimidazole-2-yl-methyl)aminomethyl]imidazole (Him-im2) and 4-[bis(1-methylimidazole-2-yl-methyl)aminoethyl]imidazole (Hhis-im2), were prepared, and [Cu(Him-im2)Cl]ClO4 (1) and [Cu(Hhis-im2)Cl]ClO4 (2) were structurally characterized by the X-ray diffraction method. Complexes 1 and 2 have a mononuclear structure with a coordinated chloride ion. The geometry of the Cu(II) center in 1 was found to be 5-coordinate trigonal-bipyramidal, whereas that of 2 was square-pyramidal. Complexes 1 and 2 showed different absorption and EPR spectra in MeOH, indicating that these compounds in solution maintain the structures revealed in the solid state. On the other hand, the reaction of Him-im2 with Cu(ClO4)2 · 6H2O under basic conditions gave a tetranuclear Cu(II) complex, [Cu4(im-im2)4](ClO4)4 (3), whereas using the ligand Hhis-im2 gave two kinds of polynuclear complexes [Cu4(his-im2)4](ClO4)4 (4) and [Cu6(his-im2)6](ClO4)6 (5) exhibiting discretely different structures. X-ray crystal structure analysis of the polynuclear complexes revealed their cyclic structures bridged by the imidazolate moiety. The geometry difference of the Cu(II) centers between 1 and 2 is thus concluded to determine the structures of tetranuclear complexes 3 and 4, respectively. Temperature dependent magnetic susceptibility measurements of complexes 3, 4, and 5 have shown an antiferromagnetic exchange interaction with a coupling constant of J = -32.5, -27.1 and -22.8 cm-1, respectively.
AB - Copper(II) complexes of N4-donor ligands containing imidazole moieties, 4-[bis(1-methylimidazole-2-yl-methyl)aminomethyl]imidazole (Him-im2) and 4-[bis(1-methylimidazole-2-yl-methyl)aminoethyl]imidazole (Hhis-im2), were prepared, and [Cu(Him-im2)Cl]ClO4 (1) and [Cu(Hhis-im2)Cl]ClO4 (2) were structurally characterized by the X-ray diffraction method. Complexes 1 and 2 have a mononuclear structure with a coordinated chloride ion. The geometry of the Cu(II) center in 1 was found to be 5-coordinate trigonal-bipyramidal, whereas that of 2 was square-pyramidal. Complexes 1 and 2 showed different absorption and EPR spectra in MeOH, indicating that these compounds in solution maintain the structures revealed in the solid state. On the other hand, the reaction of Him-im2 with Cu(ClO4)2 · 6H2O under basic conditions gave a tetranuclear Cu(II) complex, [Cu4(im-im2)4](ClO4)4 (3), whereas using the ligand Hhis-im2 gave two kinds of polynuclear complexes [Cu4(his-im2)4](ClO4)4 (4) and [Cu6(his-im2)6](ClO4)6 (5) exhibiting discretely different structures. X-ray crystal structure analysis of the polynuclear complexes revealed their cyclic structures bridged by the imidazolate moiety. The geometry difference of the Cu(II) centers between 1 and 2 is thus concluded to determine the structures of tetranuclear complexes 3 and 4, respectively. Temperature dependent magnetic susceptibility measurements of complexes 3, 4, and 5 have shown an antiferromagnetic exchange interaction with a coupling constant of J = -32.5, -27.1 and -22.8 cm-1, respectively.
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U2 - 10.1016/j.ica.2007.03.058
DO - 10.1016/j.ica.2007.03.058
M3 - Article
AN - SCOPUS:34249984699
SN - 0020-1693
VL - 360
SP - 3304
EP - 3313
JO - Inorganica Chimica Acta
JF - Inorganica Chimica Acta
IS - 10
ER -