The chemiexcitation of the chemiluminescence of lophine peroxide anions via a partially cyclic transition state

It was shown that acyclic intermediates play a role in the chemiexcitation of the chemiluminescence (CL) of lophine peroxides in addition to the dioxetane intermediates. Because the CL efficiencies of position-isomers (R)-9 and (R)-10, which theoretically give the common dioxetane intermediate, were different, the different CL efficiencies are attributable to the CL mechanism involving a partially cyclic transition structure at the chemiexcitation step. The study of isomeric 2-phenyl-4-p-X-phenyl-5-p-Y-phenyl-4-silylated peroxy-isoimidazals [(R)-9: X = CF₃, Y = F and (R)-10: X = F, Y = CF₃] confirmed the existence of lophine peroxide anion intermediates in the chemiluminescence of lophine peroxides in addition to the dioxetane intermediates.