Iron and manganese complexes comprising hexadentate monocarboxylato-containing ligands and their use for the catalysis of oxidation reactions

An iron or manganese complex having general formula (I), (II) or (III):

• [(LH)2Fe2(O)]zYq or [(L)2Fe2(O)]zYq (I)
• [LM]zYq (II)
• [LM(X)]zYq (III)
• wherein:
• M represents a metal ion selected from Fe or Mn in the II, III, IV or V oxidation state;
• L represents a monoanionic potentially hexadentate ligand containing one carboxylate group and five nitrogen donor atoms, wherein the ligand coordinates to the Fe or Mn metal ion in the complex via said carboxylate group and at least four of said nitrogen donor atoms and has general formula (IV):
• R1R1N-A-N(R1)WC(O)O− (IV)
• wherein:
• each R1 independently represents —R2—B, in which R2 represents an optionally substituted group selected from the group consisting of alkylene, alkenylene, oxyalkylene, aminoalkylene and alkylene ether, and B represents an optionally substituted heteroaryl group selected from the group consisting of pyridinyl, pyrazinyl, pyrazolyl, imidazolyl, benzimidazolyl, pyrimidinyl, triazolyl and thiazolyl;
• A represents an optionally substituted alkylene or arylene bridging group selected from the group consisting of —CH2CH2—, —CH2CH2CH2—, —CH10—, and —C6H4;
• and
• W represents a group selected from the group consisting of alkylene, arylene and arylalkylene;
• X represents a coordinating species selected from the group consisting of oxygen-coordinating terminal oxidants including peroxides, peracids, iodosylaryls, hypohalides, oxone, N-oxides and dioxygen;
• H2O, ROH, RCN, OH−, RO−, RCOO−, F−, Cl−, Br−, I−, O2−, NO3−, NO2−, ClO4−;
• and aromatic nitrogen-donors selected from the group consisting of pyridines, pyrazines, pyrazoles, imidazoles, benzimidazoles, pyrimidines, triazoles and thiazoles, with R being selected from H, optionally substituted alkyl or optionally substituted aryl;
• Y represents a non-coordinating counter ion;
• z represents the charge of the complex and is an integer which can be positive or zero;
• and
• q=z/[charge Y].