Abstract: | A series of 4‐styrylphthalhydrazides were synthesized and their chemiluminescence reactions were investigated. The chemiluminescence quantum yields as well as the emitters were variable depending on the electronic nature of the terminal substituents attached on the styryl groups. It was revealed that the excited phtha‐late ions were the emitters when they were highly fluorescent, while the energy transfer chemiluminescence from the excited phthalate ions to the phthalhydrazide anions took place when the fluorescence of the corresponding phthalate ions were very weakly fluorescent. |