Intracrystalline Kinetics Analyzed by Real-Time Monitoring of a 1,2-Dioxetane Chemiluminescence Reaction in a Single Crystal

Abstract

Adamantylideneadamantane 1,2-dioxetane (Adox), one of the most stable 1,2-dioxetanes, was used to investigate the kinetic properties of its chemiluminescent thermolytic reaction in the crystalline state by monitoring chemiluminescence (CL) in real time. Soon after heating of single crystals at 140 °C, it was found that the thermolytic reactions of Adox in the crystals proceeded with zero-order kinetics for several minutes. During the period showing the zero-order kinetics, CL intensities were dependent on the volumes of crystals, and the inside crystals were maintained in a thermal steady state with a constant thermal diffusivity. After this period, the heated crystals of Adox started to break showing different kinetics. This study indicates that a crystalline-state CL reaction is useful to track its progress in real time for analyzing the kinetics.

Crystalline-state chemiluminescence reactions of two-fluorophore-linked adamantylideneadamantane 1,2-dioxetane isomers accompanied by solid-to-solid phase transitions

“…[19][20][21][22][23][24][25][26][27] Mechanistic studies on crystalline-state CL have also been developed in recent years. [28][29][30][31] In this field, we have successfully shown an isomeric difference in the crystalline-state CL property of an Adox derivative (Ad-PA) with a fluorophore (PA) side chain (Scheme 1b). 30 Different crystal structures of the Ad-PA isomers lead to different reactivities accompanied by crystalto-melt phase transitions.…”