Characterization of a 1:1 Cu-O2 Adduct Supported by an Anilido Imine Ligand

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• 作者：Anne M. Reynolds ; Benjamin F. Gherman ; Christopher J. Cramer ; and William B. Tolman
• 刊名：Inorganic Chemistry
• 出版年：2005
• 出版时间：October 3, 2005
• 年：2005
• 卷：44
• 期：20
• 页码：6989 - 6997
• 全文大小：188K
• 年卷期：v.44,no.20(October 3, 2005)
• ISSN：1520-510X

文摘

Copper(I) complexes of sterically hindered anilido imine ligands o-C₆H₄{N(C₆H₃ⁱPr₂)}{C(R)=NC₆H₃ⁱPr₂}^- (L¹, R =H; L², R = CH₃) have been prepared and characterized by spectroscopic and X-ray crystallographic methods.These complexes are highly reactive with O₂, and in the case of L² the product of low-temperature oxygenationwas fully characterized by spectroscopic, X-ray crystallographic, and computational methods. The resonance Ramanspectrum features an isotope-sensitive vibration at 974 cm^-1 (mages/gifchars/Delta.gif" BORDER=0 >(¹⁸O) = 66 cm^-1), consistent with assignment asan O-O stretch. Despite the asymmetric coordination environment provided by the supporting anilido imine ligand,the X-ray crystal structure confirms rather symmetric side-on binding of the O₂ moiety to the copper center, and theO-O bond length of 1.392(2) Å indicates that this intermediate has significant Cu(III)-peroxo character. Theoreticalcalculations support this interpretation and predict that while a fully optimized end-on singlet geometry can beobtained, it is higher in energy than the side-on isomer by 3.5 kcal mol^-1 at the CASPT2/TZP level.