TRANSFER OF SOME ALKYL SUBSTITUTED FERROCENES FROM WATER TO CATIONIC SURFACTANT MICELLES STUDIED BY KINETIC METHOD

Binding of ferrocene and its 1,1'-dimethyl and n-butyl derivatives to dodecyl and tetradecyltrimethylammonium nitrate micellar aggregates ha s been studied at 20.0-degrees-C and ionic strength 0.02 mol dm-3 by e xamining the micellar retarding effects on the rates of iron(III) oxid ation of these substrates. Solubilization of the ferrocenes in the cat ionic micellar phase increases as the substrate hydrophobic character increases and, to a lesser extent, as the surfactant hydrocarbon chain length becomes longer. The critical micelle concentrations of the sur factants used and the incremental free energy of transfer of methylene groups of both the substrate and the surfactant from the aqueous to t he micellar pseudophase have also been determined. The present data ar e discussed and compared with those obtained previously in the presenc e of the longer homologous hexadecyltrimethylammonium nitrate and of s ome nonionic C(i)E(j) surfactants, providing evidence for the incorpor ation of the ferrocene solubilizates into the hydrophobic core of the micelle. (C) 1994 Academic Press, Inc.