Association constant for 1 (4.12 × 103
M−1/2) toward Ag+ was determined by Benesi−Hildebrand
method, and Job’s plot analysis indicated a 2:1 stoichiometry
between 1 and Ag+ (Supporting Information, Figure S9).
Reversibility of system was affirmed by adding Ag+ (5.0 equiv)
and an excess of ethylenediaminetetraacetic acid (25.0 equiv)