8-(1,4,7,10-Tetraoxa-13-azacyclopentadec-13-ylmethyl)quinolin-7-ol: synthesis and application as a highly sensitive metal cation probe.

A new metal ion probe 8-(1,4,7,10-tetraoxa-13-azacyclopentadec-13-ylmethyl)quinolin-7-ol (1a) was synthesized via a modified Mannich reaction, in which the mechanism of recognition incorporates excited-state proton transfer reactions. The remarkable differentiation in spectral properties upon metal complexation makes 1a a highly sensitive fluorescence probe.