217655-06-6Relevant academic research and scientific papers
Extended conjugation in stilbenylsquaraines
Meier, Herbert,Petermann, Ralf,Dullweber, Uta
experimental part, p. 744 - 754 (2011/10/12)
Unsymmetrical 1-aryl-3-stilbenylsquaraines 2a-e and 1,3-bis(stilbenyl)squaraines 3a-c were prepared by CC coupling reactions of the corresponding substituted arenes with derivatives of squaric acid (Schemes 2 and 3). Dialkylamino and alkoxy groups enhance the solubility of these dyes and enlarge the intramolecular charge transfer of these donor-acceptor-donor systems. The extended conjugation of the stilbene units - in comparison with arene building blocks - leads to significant bathochromic shifts in the Vis/NIR absorption spectra.
