Thermal Decomposition of Beta-Cyclodextrin Inclusion Complexes of Ferrocene and Their Derivatives

Abstract

The thermal decomposition of the solid inclusion complexes of ferrocene and its derivatives with beta-CD was studied by DTA, TG and DTG. The inclusion complexes contain crystallization water and the first decomposition stage corresponds to the dehydration of the complexes. The second stage is related to the liberation of the ferrocene and its derivatives, and the degradation of the beta-CD structure takes place in the third stage. However, the second and third stages of decomposition for some of the inclusion complexes occur in the same temperature ranges and are impossible to distinguish. The final decomposition products formed around 500 degrees C consist mainly of Fe2O3. The thermal behaviour of physical mixtures of these ferrocene derivatives and beta-CD was also investigated. The thermal analysis results show that the interaction of ferrocene and its derivatives with beta-CD is a chemical phenomenon. The ferrocene derivatives gain an additional thermal stability after inclusion complexation into the beta-CD cavity. Thermal analysis methods can be used satisfactorily for the recognition of inclusion complexation.