Synthesis, luminescence properties, and theoretical insights of N-alkyl- or N,N-dialkyl-pyrene-1-carboxamide
作者:Yosuke Niko、Susumu Kawauchi、Gen-ichi Konishi
DOI:10.1016/j.tetlet.2011.07.020
日期:2011.9
We report the synthesis and photophysical properties of N-alkyl- or N,N-dialkyl-pyrene-1-carboxamide. These derivatives, as well as pyrene, exhibited blue emission. N-Alkyl-type derivatives exhibited strong fluorescence emission (Phi(fl) = 0.61 in EtOH) in both nonpolar and polar solvents. On the other hand. N,N-dialkyl-type derivatives showed weak fluorescence emission (Phi(fl) <0.01) due to vibrational deactivation. However, in highly viscous solvents such as glycerin, the quantum efficiencies of N-alkyl-type (Phi(fl) = 0.91) and N,N-dialkyl-type (Phi(fl) = 0.082) derivatives were increased. We also investigated the fluorescence mechanism of these compounds using time-dependent density-functional theory (TD-DFT). From these results, we find that highly fluorescent pyrene-1-carboxamide derivatives can be designed by introducing an appropriate functional group at the nitrogen atom of the amide. Thus, N,N-dialkyl-type pyrene-1-carboxamide has considerable potential for use in applications such as environmental response sensors and probes. (C) 2011 Elsevier Ltd. All rights reserved.