The use of metal chelators in the synthesis of monomethine cyanine dyes

A series of monomethine cyanine dyes incorporating a transient divalent metal complex have been synthesized and characterized with elemental analyses, visible absorption, IR, 1H NMR and mass spectroscopy. The correlations between the structure and properties of these dyes have been studied. This work presents stabilized monomethine cyanine metal complex dyes that exhibit an enhanced resistance to light, heat and moisture, in comparison with non-stabilized cyanine dyes. They are, thus, of potential interest for use in optical recording media.