The dimethylamino group of DCM (4-dicyanomethylene-2-methyl-6-[p-(dimethylamino) styryl]-4H-pyran), a well-known merocyanine often used as a laser dye, has been replaced by a macrocycle (monoaza-15-crown-5) which acts also as an electron-donating substituent. The resulting fluoroionophore (DCM-crown) has almost identical photophysical properties as DCM, but upon complexation by alkaline-earth-metal cations, it undergoes drastic ...
