Molecular rotors: synthesis and evaluation as viscosity sensors

It has been shown that compounds containing the p-N,N-dialkylammobenzylidene cyanoacetate motif can serve as fluorescent non-mechanical viscosity sensors These compounds, referred to as molecular rotors, belong to a class of fluorescent probes that are known to form twisted intramolecular charge-transfer complexes in the excited state In this study we present the synthesis and spectroscopic characterization of these compounds as viscosity sensors The effects of the molecular structure and electronic density of these rotors to the emission wavelength, fluorescence intensity, and viscosity sensitivity are discussed (C) 2010 Elsevier Ltd All rights reserved