| Abstract: | A highly colored polystyrene derivative bearing side chain chromophores composed of dialkylanilino donor and cyano‐based acceptor groups, prepared by atom‐economic click postfunctionalization, displays the dual colorimetric detection behavior of several metal ions based on the specific interactions with different nitrogen atoms. Hard to borderline metal ions, such as Fe3+, Fe2+, and Sn2+, are always recognized by the dialkylanilino nitrogen atom, resulting in a decrease in the charge‐transfer (CT) band intensity of the donor–acceptor chromophores. On the other hand, the recognition site of a soft metal ion of Ag+ is the cyano nitrogen atom due to the readily formed multivalent coordination, which produces a bathochromic shift of the CT band. |
