Synthesis and characterisation of redox-active conjugated macrocycles

Abstract

Fully conjugated macrocycles have attracted much interest during the past few years, as the demand for new materials in nanotechnology is continuously rising. Due to the variety of excellent properties that they can show, they are most suitable for application in the area of organic electronics. However, they are surprisingly underexplored regarding various state-of-the-art applications in this area. This may be due to the lack of straightforward syntheses and the often low yields of cyclisation reactions. In the course of this work macrocycles with four different cavity sizes were synthesised. Furthermore, the effect of different alkyl chain lengths on the properties of the macrocycles were investigated. The macrocycles were prepared via Perkin cyclisation of diacetic acid and diglyoxylic acid precursors, for which synthetic routes had to be developed. The obtained molecules were characterised by absorption and photoluminescence measurements. Moreover, in collaboration with the Institute of Physical Chemistry at the Polish Academy of Sciences, the redox properties of the macrocycles were analysed by cyclic voltammetry (CV) measurements. Further conversion of the ester groups to other functional groups, such as cyano groups, was tested using model compounds designed specifically for this purpose. Model compounds for an alternative approach to conjugated macrocycles with cyano groups via Benzoin condensation and further conversion were also prepared. First attempts to convert these model compounds were carried out.