Acireductone Dioxygenase- (ARD-) Type Reactivity of a Nickel(II) Complex Having Monoanionic Coordination of a Model Substrate: Product Identification and Comparisons to Unreactive Analogues
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- 作者：Ewa Szajna-Fuller ; Katarzyna Rudzka ; Atta M. Arif ; Lisa M. Berreau
- 刊名：Inorganic Chemistry
- 出版年：2007
- 出版时间：July 9, 2007
- 年：2007
- 卷：46
- 期：14
- 页码：5499 - 5507
- 全文大小：172K
- 年卷期：v.46,no.14(July 9, 2007)
- ISSN：1520-510X
文摘
A mononuclear Ni(II) complex ([(6-Ph2TPA)Ni(PhC(O)C(OH)C(O)Ph)]ClO4 (1)), supported by the 6-Ph2TPA chelateligand (6-Ph2TPA = N,N-bis((6-phenyl-2-pyridyl)methyl)-N-((2-pyridyl)methyl)amine) and containing a cis-
-keto-enolate ligand having a C2 hydroxyl substituent, undergoes reaction with O2 to produce a Ni(II) monobenzoatecomplex ([(6-Ph2TPA)Ni(O2CPh)]ClO4 (3)), CO, benzil (PhC(O)C(O)Ph), benzoic acid, and other minor unidentifiedphenyl-containing products. Complex 3 has been identified through independent synthesis and was characterizedby X-ray crystallography, 1H NMR, FAB-MS, FTIR, and elemental analysis. A series of cis--keto-enolate Ni(II)complexes supported by the 6-Ph2TPA ligand ([(6-Ph2TPA)Ni(PhC(O)CHC(O)Ph)]ClO4 (4), [(6-Ph2TPA)Ni(CH3C(O)CHC(O)CH3)]ClO4 (5), and [(6-Ph2TPA)Ni(PhC(O)CHC(O)C(O)Ph) (6)) have been prepared and characterized.While these complexes exhibit structural and/or spectroscopic similarity to 1, all are unreactive with O2. The resultsof this study are discussed in terms of relevance to Ni(II)-containing acireductone dioxygenase enzymes, as wellas in the context of recently reported cofactor-free, quercetin, and -diketone dioxygenases.
-keto-enolate ligand having a C2 hydroxyl substituent, undergoes reaction with O2 to produce a Ni(II) monobenzoatecomplex ([(6-Ph2TPA)Ni(O2CPh)]ClO4 (3)), CO, benzil (PhC(O)C(O)Ph), benzoic acid, and other minor unidentifiedphenyl-containing products. Complex 3 has been identified through independent synthesis and was characterizedby X-ray crystallography, 1H NMR, FAB-MS, FTIR, and elemental analysis. A series of cis--keto-enolate Ni(II)complexes supported by the 6-Ph2TPA ligand ([(6-Ph2TPA)Ni(PhC(O)CHC(O)Ph)]ClO4 (4), [(6-Ph2TPA)Ni(CH3C(O)CHC(O)CH3)]ClO4 (5), and [(6-Ph2TPA)Ni(PhC(O)CHC(O)C(O)Ph) (6)) have been prepared and characterized.While these complexes exhibit structural and/or spectroscopic similarity to 1, all are unreactive with O2. The resultsof this study are discussed in terms of relevance to Ni(II)-containing acireductone dioxygenase enzymes, as wellas in the context of recently reported cofactor-free, quercetin, and -diketone dioxygenases.