Low temperature reaction of [Fe(TPA)(CH₃CN)₂]²⁺ with excess 3-chloroperoxybenzoic acid in semi-frozen acetonitrile; EPR detection of an acylperoxo iron(III) adduct

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• 作者：Gregorio Guisado-Barrios ; Yiteng Zhang ; Andrew M. Harkins ; David T. Richens ; ^{richens@nmsu.edu}
• 关键词：TPA ; Acylperoxoiron ; EPR ; Cyclohexene epoxidation ; mCPBA ; Salicylate
• 刊名：Inorganic Chemistry Communications
• 出版年：2012
• 出版时间：June, 2012
• 年：2012
• 卷：20
• 期：Complete
• 页码：81-85
• 全文大小：716 K

文摘

Treatment of [(TPA)Fe^II(CH₃CN)₂]²⁺ (TPA = tris(2-pyridylmethyl)amine) with excess (?#xA0;2 Eq) of 3-chloroperoxybenzoic acid (mCPBA) in semi-frozen acetonitrile in liquid N₂ vapour generates a rhombic EPR signal assigned to the S = ? low spin acylperoxoiron(III) species [(TPA)Fe(O₃CC₆H₄-3Cl)(CH₃CN)]²⁺ 5; the elusive precursor on the pathway to [(TPA)Fe^III(5-chlorosalicylate)]⁺ 4 via putative [(TPA)Fe^V(O)(O₂CC₆H₄-3Cl)]²⁺. Formation of cyclohexene epoxide in the presence of added cyclohexene at low temperatures (<?0 ¡ãC) suggests that intermolecular alkene epoxidation competes successfully with the intramolecular reactions involving 5 to generate 4.