Abstract

AbstractThe complexation reactions between the Tl+ ion and large crown ethers dibenzo‐30‐crown‐10 (DB30C10), dibenzo‐27‐crown‐9 (DB27C9), dibenzo‐24‐crown‐8 (DB24C8) and dibenzo‐21‐crown‐7 (DB21C7) were studied in different acetonitrile‐water mixtures at 25°C using an a.c. polarographic technique. The stoichiometry and stability of the complexes were determined by monitoring the shift in peak potential of the polarographic waves of the metal ion against the crown concentration. In all solvent mixtures used, the stability of the resulting 1:1 complexes was found to vary in the order DC24C8 » DB30C10 > DB21C7 > DB27C9 > DB24C8. There is an inverse relationship between the complex formation constants and the amount of water in the mixed solvent. In all cases, a linear relation was observed between log Kf and the mole fraction of acetonitrile in its mixtures with water.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call