Synthesis and photophysics of 3, 4, 9, 10 perylene tetracarboxylic diimide dendrimers.

摘要

Perylene dyes are photostable and have been used in a variety of applications, including textiles, automobile and general paints and plastics. Their poor solubility has been a hindrance in their potential use as laser dyes, surface modifiers and electrochemical coatings. Since the late 1950s a variety of synthetic schemes have been applied to modify perylene and perylene derivatives in order to improve their solubility. Many of these dyes are derived from 3, 4, 9, 10 perylene dianhydride, which can derivatized by imidization to 3, 4, 9, 10 perylene tetracarboxylic diimide, also called 3, 4, 9, 10 perylene bis(dicarboximide). These are well documented in the literature. This dissertation will focus on a modification of these diimides and the photophysics of these derivatives.; Following a divergent Tomalia-like approach perylene tetracarboxylic diimide core dendrimers were synthesized using a Michael's addition followed by a methyl ester-amine displacement. Half-generation methyl ester-terminated, four-armed dendrimers have been well characterized and their photophysics has been well studied in organic solutions and attached to SiO2. First-generation ethylene diamine-terminated dendrimers have also been well studied in solution.; Our perylene diimide ester-terminated dendrimers exhibit linear Beer-Lambert absorption behavior. Extensive fluorescence quenching studies have been conducted on the ester- and ethylene diamine-terminated dendrimers, using N, N diethylaniline, 1, 3, 5-trimethoxybenzene and Dabco. All of these compounds exhibit dynamic fluorescence quenching. The amine-terminated dendrimer also exhibits static quenching via complexation. Both of these dendrimers exhibit significant internal fluorescence quenching, as compared to the model compound N, N' -bis(2, 5-di-tert-butylphenyl)-3, 4, 9, 10-perylenebis(dicarboximide), which does not contain tertiary amines. The fluorescence intensity of the dendrimers increases dramatically upon protonation by trifluoroacetic acid, but not for the model compound. It has been hypothesized that the protonation deactivates the fluorescence quenching effected by the two tertiary amines on the dendrimers.