Synthesis and evaluation of aryl oxalates as peroxyoxalate chemiluminescence reagents

Abstract

Eight aryl oxalates having an alkyoxy moiety were synthesised to improve the solubility in acetonitrile for the peroxyoxalate chemiluminescence reaction system. Of these, bis[2-(3,6-dioxaheptyloxycarbonyl)-4-fluorophenyl] oxalate showed the highest solubility (1685 mM). To evaluate these esters together with some known aryl oxalates as chemiluminescence reagents, a simple and rapid method using a flow injection system was developed. The chemiluminescence reaction system consisted of an oxalate, hydrogen peroxide, triethylamine and 9,10-diphenylanthracene in acetonitrile. Of the oxalates synthesised, bis[2-(3,6-dioxaheptyloxycarbonyl)-4-bromophenyl] oxalate gave the highest intensity, which was about 100 times lower than that of bis(2,4-dinitrophenyl) oxalate. However, the chemiluminescence intensities of the oxalates synthesised continued for a far longer period of time than those of commercially available oxalates.