The Primary Process of the Photochemical Formation of 1-Nitrenopyrene

The primary process of the photo-decomposition of 1-azidopyrene (Py–N3) was studied with the aid of nanosecond time-resolved laser photolysis. An excited singlet 1-nitrenopyrene (Py–N) was identified as an intermediate for the formation of the ground triplet nitrene. The direct photo-decomposition of 1-azidopyrene occurs through Py–N3* (singlet)→Py–N* (singlet)→Py–N (triplet). The lifetime of the excited singlet nitrene was found to be 22 ns at room temperature in benzene and was found to be slightly longer at 77 K.