71344-20-2Relevant academic research and scientific papers
Photocleavage of pyridyl-based aromatic polyureas
Mwaura, Jeremiah,Yang, Baocheng,Li, Rongfu,Morton, Martha,Papadimitrakopoulos, Fotios
, p. 9775 - 9783 (2007/10/03)
The photophysical properties of a metal chelating pyridyl-based aromatic ureas and poly-(1,4-phenylene-2,6-pyridylurea) were investigated. In their solution state and upon exposure to 365 nm UV radiation, these low and high molecular weight compounds were found to cleave the urea linkage nearly quantitatively, generating the corresponding amine-terminated subunits and CO2. Through a series of model compounds along with nuclear magnetic resonance (NMR), UV/vis absorption, and fluorescence spectroscopy characterization, the photocleavage process was delinated as a function of UV dose, O2, and water. The presence of water was found crucial to this photocleavage process with O2 playing a role only in subsequent oxidation of resulting amine functionalities. The experimental results support a light-assisted hydrolysis of the urea bond as the most plausible photocleavage mechanism. The photocleavage of such pyridyl-based ureas can potentially find usages in light-assisted base generation and/or for releasing metal cations.
