Mechanistic Tuning of Hydrocarbon Oxidations with H2O2, Catalyzed by Hexacoordinate Ferrous Complexes

✍ Scribed by Yasmina Mekmouche; Stéphane Ménage; Jacques Pécaut; Colette Lebrun; Lee Reilly; Volker Schuenemann; Alfred Trautwein; Marc Fontecave

• Publisher: John Wiley and Sons
• Year: 2004
• Tongue: English
• Weight: 163 KB
• Volume: 2004
• Category: Article
• ISSN: 1434-1948
• DOI: 10.1002/ejic.200300926

✦ Synopsis

Abstract

A comparison of the catalytic properties of a series of Fe^II^LXY complexes on oxidation reactions with H~2~O~2~, [L = N,N′‐bis(pyridin‐2‐yl‐methyl)‐N,N′‐bis(3,4,5‐trimethoxybenzyl)ethane‐1,2‐diamine] indicates that the lability of the X and Y ligands (Cl^−^ or CH~3~CN) determines the nature of the oxidation pathway. The absence of a labile site in the complex, i.e. when X = Y = Cl^−^, causes the reaction to proceed via a Fenton pathway (generation of hydroxyl radicals, exclusively). The presence of two labile CH~3~CN ligands (X = Y = CH~3~CN) allows the catalysis to proceed through a metal‐based mechanism, whereas in the case of a complex with only one labile ligand (X = Cl^−^ and Y = CH~3~CN), the reaction is less controlled by the metal. We wish to emphasize that the cleavage of the O−O bond in the Fe−OOH moeity, a key intermediate in the reaction, is different in the last two cases. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)