Design, synthesis and characterisation of porphyrin, fullerene and napthalene diimide conjugates of Tröger's base
thesisposted on 2022-03-28, 23:09 authored by Md Imam Ansari
Porphyrins, naphthalene diimide and fullerene-C60 are particularly important chromophores that have been used in light-energy conversion research and the design and synthesis of artificial photosynthetic systems. The electron donor (porphyrins) and electron acceptors (naphthalene diimide or fullerene-C60) play key roles in mimicking the photosynthetic antenna-reaction centre of plants. The main aim of this thesis is to provide further insight into the construction of donor-acceptor compounds separated by a well-defined V-shaped bridging molecule. Various linear and conjugated porphyrin arrays have been developed to better understand structure-electronic properties relationship between the two chromophores but the emphasis of this thesis is the development of synthetic methods for the construction of these donor-acceptor systems. In particular, we focus on Tröger's base as a V-shaped bridge molecule between two chromophores. This thesis first describes the synthesis of new Tröger's bases with the desired functional groups such as nitro, amino, ester, alcohol and aldehyde then postmodification of Tröger's base to append chromophores. Novel architectures were made such as symmetric porphyrin dyads using two different types of porphyrin and hybrid porphyrin-Tröger's base-naphthalene diimide and porphyrin-Tröger's base-C60 dyads. In addition, bis-naphthalene diimide Tröger's base and Tröger's base-C60 were made in order to develop methodology for postmodification of TB to append NDI and C60, respectively. Preliminary photophysical characterisation (fluorescence and UV/Vis) is presented but charge transfer properties of selected compounds will be studied by cyclic voltammetry and transient absorbent spectroscopy in the future. All Tröger's base compounds made are racemic.