Complexation between Iron(II) and 8-hydroxyquinoline and its 2- and 5-methyl substitutes in KFe[Fe(CN)(6)] gelatin-immobilized matrix materials

The complexation reactions in the iron(In) hexacyanoferrate(II) gelatin-imm obilized matrix materials contacting aqueous solutions of 8-hydroxyquinolin e or its 2- and 5-methyl substitutes in alkaline medium (pH 12.0) were stud ied. It is shown that immobilized iron(III) hexacyanoferrate(II) first unde rgoes alkaline destruction to the Fe(II) and Fe(III) hydroxides or oxohydro xides, and only thereafter the chelate compounds of the FeL2 type (L- is si ngly deprotonated ligand form) are formed. It is found that, in all cases, the redox Fe(II) --> Fe(III) process occurs to a degree with the formation of chelates of FeL3 type.