Aminoisoquinolines as colorimetric Hg2+ sensors: the importance of molecular structure and sacrificial base

Here it is shown that 3-phenyl-2-amino isoquinoline acts as a simple mercury sensor. It is simple to synthesize. The molecule requires base/buffer to bind in a 1:1 stoichiometry with mercury ion, however. Otherwise, it acts as a sacrificial base, presumably to pick up a proton liberated during binding. This binding is characterized quantitatively.