Photoactivatable turn-on fluorescence based on the photo-cleavage of the C–Br bond in 1,2-bis(5-(bromoethyl)benzoxazol-2-yl)ethane

Abstract

This paper describes photoactivatable turn-on fluorescence based on the photo-cleavage of the C–Br bond in 1,2-bis(5-(bromoethyl)benzoxazol-2-yl)ethane (1) in both solution and in a polymeric thin film. It was found that 1 exhibited very weak fluorescence in both solution and in a PMMA thin film, upon irradiation with 365 nm light, a strong fluorescence was detected. The strong fluorescence attributed to the photo-product resulted from the photo-induced cleavage of the C–Br bond in 1. Moreover, it was also found that the photo-cleavage of the C–Br bond in 1 can be performed using a two-photon induced process, and upon irradiation on a 1-PMMA thin film with a 780 nm femtosecond laser, finely resolved fluorescence images are obtained.