Singlet-oxygen Chemiluminescence from Heated Crystal Samples of 9,10-Diphenylanthracene Endoperoxides

Thermolytic reactions of 9,10-diphenylanthracene endoperoxide (1) and its derivatives having deuterated phenyl groups and phenyl groups with fluorinated substituents were investigated as chemiluminescence (CL) reactions proceeding by heating crystal samples. While heated crystals of 1 showed negligible CL, CL emissions from singlet oxygen (1O2) generated by thermolyses of the derivatives were observable in the heated solid-liquid mixture states, indicating that the modifications for the derivatives were effective to suppress the 1O2 deactivation. By heating crystal samples of 9,10-diphenylanthracene endoperoxide derivatives having deuterated phenyl groups and phenyl groups with fluorinated substituents over 150 °C, we could observe near-infrared chemiluminescence from singlet oxygen generated by thermolytic reactions of the derivatives in the heated solid-liquid mixture states, while heated crystals of 9,10-diphenylanthracene endoperoxide showed negligible chemiluminescence.