Multichromophoric perylene bisimide dyes

ABSTRACT: Chromophores are responsible for the color of matter. The control of molecular interactions in multichromophores lead to functional dyes with novel properties. Furthermore, tailormade spectroscopic properties could be achieved, which are a prerequisite for applications that require dyes with absorption and emission in a specific region of the visible spectrum. With this special interest, we targeted to synthesize a multichromophoric macromolecule containing two different chromophores – a perylene and naphthalene. We have designed a molecular architecture of, and synthesized a novel multichromphoric macromolecule, N,N’-bis-{N-(3-[4-(3-amino-propyl)-piperazin-1-yl]-propyl)-N’-[1-dehdroabiety]-1,4,5,8-naphthalenetetracarboxydiimidly}-3,4,9,10 perylenebis(dicarboximide)bisimides (NPM) which was carried out in three consecutive steps. Our focus was also to enlarge both the absorption and emission ranges of the macromolecule and to investigate consequent optical properties. The first step includes the synthesis of a perylene dye, N-N’-bis-{3-[4-(3-amino-propyl)- piperazin-1-yl]-propyl}-3,4,9,10-perylenebis(dicarboximide) (PDI) where as in the second step, a naphthalene monoimide, N-(1-dehydroabietyl)-1,4,5,8-naphthalenetetracarboxylic-1,8-anhydride-4,5-imide (NMI) was synthesized. Finally, the designed macromolecule dye (NPM) was synthesized by using the above synthesized compounds, PDI and NMI. All the synthesized compounds were characterized in detail by IR, MS, NMR, UV-vis, DSC and TGA measurements. A much enlarged absorption (325 nm – 550 nm) and emission (375 nm – 700 nm) ranges were achieved by the synthesized macromolecule dye which was appreciably soluble in most of the commercial organic solvents. All the three synthesized compounds were photochemically and thermally stable and found no glass transition temperature in the DSC runs until 300 oC. The fluorescence quantum yields of the compounds were measured and PDI was reported high quantum yield among the three synthesized compounds. Several optical parameters were also calculated and reported. …………………………………………………………………………………………………………………………………………………………………………………………………………