Oxidative condensation and chemiluminescence of 5-amino-2,3-dihydro-1,4-phtalazinedione

The oxidative condensation of (5-amino-2,3-dihydro-1,4-phtalazinedione) luminol was carried out under their oxidation by (NH4)2S2O8 and KIO3 in the mixed water-organic (namely dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF) or N-methyl-2-pyrrolidinone (MPD)) solvent under the volume ratio 1:9. The structure of the products was studied by IR and Raman spectroscopy, elemental analysis and the derivatographic method. It was determined that oxidation by KIO3 (E = 1.085 V) occurs on the amide nitrogen atoms, while in the case of (NH4)2S2O8 (E = 2.05 V) it occurs on the amino-group. The structure and thermal stability of the obtained products is determined by the nature of the oxidant. The active decomposition of luminol begins at td = 334.5 °C, while for the specimens of the polyluminols, which were synthesized in the water-DMSO and water-MPD mixtures, td equals 356.7 and 409.1 °C respectively. The worst thermal stability has products of luminol oxidation by KIO3 (td = 282.5 °C). The mechanism of the luminol oxidative polymerization by (NH4)2S2O8 and KIO3 has been proposed.