Abstract
Novel tetraaza macrocyclic Schiff base ligands (L1 and L2) having a chromophore have been synthesized by reaction of 7-chloro-4-nitrobenzoxadiazole with the parent macrocyclic ligands, 5, 7, 12, 14-tetramethy1-1, 4, 8, 11-tetraazacyclotetradeca-1, 5, 7, 12-tetraene and 6, 8, 15, 17-tetramethyl-dibenzo-5, 9, 14, 18-tetraazacyclotetradecene, respectively. These ligands have been found to complex selectively with a copper(II) ion. Under optimal complexation conditions, L1 afforded a higher molar extinction coefficient (logε=4.22) than L2, so that L1 has been applied to a spectrophotometric reagent for the determination of copper(II) ion by FIA. Two systems, a parallel flow method and a merging zone method, have been examined and the latter has been found to be superior to the former. This is due to that the complexation is less complete in the former than in the latter case. Although the sensitivity to the copper(II) ion obtained under the optimal conditions is comparable to that obtained in a batch system, the method exhibits advantages such as less interference from nickel(II) ion during the determination and shortening of the time required for the determination.
