Preparation and characterization of cyclodextrin complexes of the insecticides aldicarb and sulprofos

Abstract

The beta-cyclodextrin (BCD) complexes of the insecticides sulprofos and aldicarb have been prepared in an aqueous medium. Attempts to form a BCD complex of the insecticide thiodicarb were apparently unsuccessful. The BCD complexes were characterized by solubility properties, elemental analyses, and spectral studies. Spectral studies included ultraviolet, infrared, proton NMR, and 13C NMR spectroscopy. The spectral differences between the BCD complex and its individual components were greatest in the case of aldicarb, providing evidence confirming the formation of a true inclusion complex. Since the spectral differences between the sulprofos-BCD complex and its components were small, it was analyzed by differential scanning calorimetry (DSC). The DSC thermogram of the complex differed markedly from that of sulprofos or BCD, suggesting the formation of an inclusion complex; however, an external associative complex cannot be ruled out.