1998 Fiscal Year Final Research Report Summary
Structural and solution chemistries of five-coordinate copper(II) complexes
| Project/Area Number |
09640656
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Inorganic chemistry
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| Research Institution | Iwate University |
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Principal Investigator |
MURAKAMI Tasuku Iwate Univ., Education, Prof., 教育学部, 教授 (60006327)
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| Co-Investigator(Kenkyū-buntansha) |
KIKUCHI Yoichi Iwate Univ., Education, Assoc.Prof., 教育学部, 助教授 (50241493)
TAKEI Takaaki Iwate Univ., Education, Assoc.Prof., 教育学部, 助教授 (10109150)
KITA Shoichi Hirosaki Univ., Science & Technology, Assoc.Prof., 理工学部, 助教授 (80142834)
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| Project Period (FY) |
1997 – 1998
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| Keywords | copper(II) complex / five-coordinate / mixed-ligand complex / X-ray analysis / stability |
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| Research Abstract |
1. Five-coordinate Cu(II) ternary complexes containing some kinds of Linear triamines as terdentate and. amino acids and diamines as bidentate have been synthesized and characterized by means of X-ray single crystal analyses and spectral measurements. Stabilities of the five-coordinate species were also investigated by potentiometric titrations.
2. The ternary complexes containing N,N,N', N", N"-pentamethyldiethylenetriamine (pmdt) and L-valine (L-val) and alpha-aminoisobutyric acid (aiba), [Cu(pmdt)(L-val)]CLO_4 and Cu(pmdt)(aiba)]CLO_4, were approximately regular trigonal bipyramidal with trigonal factors of 81 and 94%. The ternary complex with 2,2'-dipicolylamine (dpa) and L phenylalanine (L-phe), [Cu(dpa)(L-phe)]CLO_4, was slightly distorted square pyramidal, and there was no intramolecular aromatic ring stacking between the pyridyl group of dpa and the phenyl group of L-phe, while the intermolecular stacking was observed. The ternary complexes containing N,N- dimethyl-N'-(2-pyridyhnethyl)ethylene diamine (p yen) and an amino acid exhibited also square pyramidal spectra. Some complexes with dpa and an amino acid showed unique spectral behavior : the spectrum in solid state is significantly different from that in solution.
3. The stability constant of the ternary five-coordinate complexes containing dpa and pyen as a terdentate ligand and an aromatic amino acid as a bidentate was significantly large compared with those with alkyl- and hydroxyalkyl-substituted amino acids, indicating a hydrophobic intramolecular interaction between the pyridine ring of dpa and pyen and the aromatic sidechains of the amino acids.
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