Highly selective response of bipyridyl-incorporated acetyelene dye for zinc acetate.

In this paper, we prepared bpy-modified acetylene dye 2 that contains 2,2'-bipyridine moiety in the center with symmetrically substituted flexible derivatives at both ends. Upon exposure toward various metal salts, 2 revealed a highly selective optical response to Zn(2+) with AcO(-) as a counteranion, which is evidenced by large red shift and significant enhancement in emission intensity. Such a peculiar response to single zinc compound, as far as we are aware, has not been reported elsewhere.