Solvent Effects on the Conversion of Dicopper(II) -2:
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- 作者：Hong-Chang Liang ; Mark J. Henson ; Lanying Q. Hatcher ; Michael A. Vance ; Christiana Xin Zhang ; David Lahti ; Susan Kaderli ; Roger D. Sommer ; Arnold L. Rheingold ; Andreas D. Zuberbü ; hler ; Edward I. S
- 刊名：Inorganic Chemistry
- 出版年：2004
- 出版时间：July 12, 2004
- 年：2004
- 卷：43
- 期：14
- 页码：4115 - 4117
- 全文大小：112K
- 年卷期：v.43,no.14(July 12, 2004)
- ISSN：1520-510X
文摘
A new tridentate ligand, PYAN, is employed to investigate solventinfluences for dioxygen reactivity with [Cu(PYAN)(MeCN)]B(C6F5)4(1). Stopped-flow kinetic studies confirm that the adducts [{CuII(PYAN)}2(O2)][B(C6F5)4]2 (2Peroxo) and [{CuIII(PYAN)}2(O)2][B(C6F5)4]2(2Oxo) are in rapid equilibrium. Thermodynamic parameters for theequilibrium between 2Peroxo and 2Oxo are as follows: THF, 
H
~ -15.7 kJ/mol, S ~ -83 J/K·mol; acetone, H ~ -15.8kJ/mol, S ~ -76 J/K·mol. UV-visible absorption and resonanceRaman spectroscopic signatures demonstrate that the equilibriumis highly solvent dependent; the mixture is mostly 2Peroxo inCH2Cl2, but there are significantly increasing quantities of 2Oxo alongthe series methylene chloride 
diethyl ether acetone tetrahydrofuran (THF). Copper(II)-Neq stretches (239, 243, 244,and 246 cm-1 in CH2Cl2, Et2O, acetone, and THF, respectively)are identified for 2Peroxo, but they are not seen in 2Oxo, revealingfor the first time direct evidence for solvent coordination in themore open 2Peroxo structure.
H~ -15.7 kJ/mol, S ~ -83 J/K·mol; acetone, H ~ -15.8kJ/mol, S ~ -76 J/K·mol. UV-visible absorption and resonanceRaman spectroscopic signatures demonstrate that the equilibriumis highly solvent dependent; the mixture is mostly 2Peroxo inCH2Cl2, but there are significantly increasing quantities of 2Oxo alongthe series methylene chloride diethyl ether acetone tetrahydrofuran (THF). Copper(II)-Neq stretches (239, 243, 244,and 246 cm-1 in CH2Cl2, Et2O, acetone, and THF, respectively)are identified for 2Peroxo, but they are not seen in 2Oxo, revealingfor the first time direct evidence for solvent coordination in themore open 2Peroxo structure.