Highly soluble perylene diimide and oligomeric diimide dyes combining perylene and hexa(ethylene glycol) units: Synthesis, characterization, optical and electrochemical properties

A novel, soluble, perylene oligomeric diimide dye, termed EOPPI was synthesized in high yield; for comparison, a small dye molecule, termed EOPDI, was also synthesized; both products readily dissolved in a wide range of organic solvents. The compounds were characterized using NMR, IR, MS, UV-vis, MS, GC-MS, HRMS, DSC, TGA, elemental analysis and cyclic voltammetry. The average molecular mass of EOPPI was 4460, its intrinsic viscosity was 0.3 dl g(-1) in m-cresol at 20 degrees C. The band gap energy (E-g), LUMO and HOMO energy values were 2.25, -3.78 and -6.03 eV for the small dye molecule and 2.24, -3.85 and -6.09 eV for the oligomer, respectively. The temperatures at which the monomer and oligomer began to lose mass were 300 and 375 degrees C, respectively. The oligomer showed concentration-dependent color tunability. (C) 2008 Elsevier Ltd. All rights reserved.