A method for producing manganese complex compounds of the formula in which M is selected from manganese and iron in oxidation state III or IV, but where at least one M is a manganese in oxidation state III or IV, X independently of the others is a coordinating or bridging species, selected from H 2 O, O 2 2-, O 2 -, O 2-, OH-, HO 2 -, SH -, S 2-, SO, Cl -, N 3-, SCN -, N 3 -, RCOO -, NH 2 - and NR 3, where R is a radical selected from H, alkyl and aryl, L is 1,4,7-trimethyl-1,4,7-triazacyclononane, z is an integer from -4 to +4, Y is a mono- or multivalent counterion from the group hexafluorophosphate, perchlorate or tetraphenylborate, which leads to the charge neutrality of the complex, and q is an integer from 1 to 4, which comprises the following steps: a) reacting one or more divalent metal salts, where the one or more divalent metal salts are selected from divalent manganese and iron salts and at least one divalent metal salt is a divalent manganese salt, with the ligand L in water as solvent for forming a coordination compound of the one or more divalent metal salts and the ligand L, b) oxidation of the coordination compound from step a) with an oxidizing agent, where at the same time a pH from 11 to 14 is maintained, for converting the metal M from the divalent state to the tri- and/or tetravalent state, c) reducing the pH of the reaction mixture to a pH from 4 to 9, preferably from 5 to 8, and separating off any metal oxides or hydroxides of the metal M formed and d) addition of a salt of the formula Me z Y q, in which Me is an alkali metal ion, an ammonium ion or an alkanolammonium ion, and Y, z and q have the stated meanings, at a pH from 4 to 9 and preferably from 5 to 8, and where the counterion salt Me z Y q is only introduced into the reaction mixture and reacted after the oxidation step and the removal of the metal oxides and metal hydroxides formed. M is selected from manganese and iron in oxidation state III or IV, but where at least one M is a manganese in oxidation state III or IV, X independently of the others is a coordinating or bridging species, selected from H 2 O, O 2 2-, O 2 -, O 2-, OH-, HO 2 -, SH -, S 2-, SO, Cl -, N 3-, SCN -, N 3 -, RCOO -, NH 2 - and NR 3, where R is a radical selected from H, alkyl and aryl, L is 1,4,7-trimethyl-1,4,7-triazacyclononane, z is an integer from -4 to +4, Y is a mono- or multivalent counterion from the group hexafluorophosphate, perchlorate or tetraphenylborate, which leads to the charge neutrality of the complex, and q is an integer from 1 to 4, a) reacting one or more divalent metal salts, where the one or more divalent metal salts are selected from divalent manganese and iron salts and at least one divalent metal salt is a divalent manganese salt, with the ligand L in water as solvent for forming a coordination compound of the one or more divalent metal salts and the ligand L, b) oxidation of the coordination compound from step a) with an oxidizing agent, where at the same time a pH from 11 to 14 is maintained, for converting the metal M from the divalent state to the tri- and/or tetravalent state, c) reducing the pH of the reaction mixture to a pH from 4 to 9, preferably from 5 to 8, and separating off any metal oxides or hydroxides of the metal M formed and d) addition of a salt of the formula Me z Y q, in which Me is an alkali metal ion, an ammonium ion or an alkanolammonium ion, and Y, z and q have the stated meanings, at a pH from 4 to 9 and preferably from 5 to 8, and where the counterion salt Me z Y q is only introduced into the reaction mixture and reacted after the oxidation step and the removal of the metal oxides and metal hydroxides formed.