Chemiluminescence of 4-styrylphthal-hydrazides with crown ether as ionophore

Two 4-styrylphthalhydrazides bearing crown ether moieties as ionophores were prepared and their chemiluminescence (CL) behaviour was investigated. Their aerobic oxidation in the presence of excess tert-BuOK in DMSO provided the CL with much shorter emission wavelengths than those of the corresponding phthalate dianions, indicating that the emission arose from the excited phthalates incorporated with potassium ions at the ionophore sites. Such incorporation of potassium ions with the crown sites also reduced the fluorescence intensities of the phthalate dianions which caused an energy transfer CL, resulting in the additional emissions of the phthalhydrazide monoanions in much longer wavelength regions. On the other hand, only the emission from the excited phthalate dianion was detected under aqueous conditions using aqueous hydrogen peroxide in acetonitrile as the oxidant, but no meaningful difference in the CL intensity depending on the kind of metal cations was observed.