Date of Degree
Sanjai Kumar Pathak
Materials Chemistry | Organic Chemistry
Perylene, synthesis, liquid crystal, unsymmetrical
Perylene tetracarboxylic derivatives are considered good n-type semi-conductors. In past decades, there has been extensive study on their synthesis and electronic properties. Because of the high electron affinity, the ability to form π-π stacks, they have been widely utilized in organic photovoltaic solar cells, field-effect transistors and light-emitting diodes. Many of those applications prefer unsymmetrically substituted perylene tetracarboxylic derivatives. Perylene monoanhydrides are the most versatile intermediates for the preparation of unsymmetrically substituted perylene tetracarboxylic derivatives. In this thesis, I focused on introducing new synthesis methods for perylene monoanhydrides with labile functional group and their potential applications in organic optoelectronics.
In Chapter 1, it is the general background of perylene tetracarboxylic derivatives including (a) redox properties, optical properties and liquid crystalline phase, (b) synthesis routes, (c) perylene diimides oligomers and their properties.
In Chapter 2, perylene monoimide monoanhydride dimer was prepared and applied as an intermediate to synthesize perylene oligomers from monomer to pentamer, breaking the previous record of trimer. And their absorption coefficients and reduction potentials were studied.
In Chapter 3, a tandem palladium-catalyzed deallylation/cyclization reaction was designed to occur under a mild condition: weakly acidic (acetic acid) and room temperature, which enables the synthesis of perylene monoanhydrides with many labile R groups for the first time.
In Chapter 4, an unsymmetrically substituted perylene monoanhydride diester was prepared through a “one-pot three-step” synthetic strategy and served as the key starting material for a functional group-tolerant, transition metal-free synthesis of perylene monoanhydrides. Perylene monoanhydrides with a wide range of viable functional groups were prepared which could be further converted to other unsymmetrically substituted perylene derivatives.
In Chapter 5, by tuning the length of the alkyl swallow tail on perylene tetracarboxylic derivatives, a bundled-stack discotic columnar liquid crystalline phase was observed, which is the first perylene compounds that display discotic columnar liquid crystalline phase within one or two alkyl chains. And highly robust charge transport performance is expected.
Novel synthesis methods for preparing perylene tetracarboxylic derivatives are important as providing new perylene-based materials. The characterization is critical as well, which including infrared spectroscopy, ultra-violet, nuclear magnetic resonance, differential scanning calorimetry, gel permeation chromatography and wide-angle X-ray diffraction. In general, the achievements in my research contributed a significant advance in the field of developing perylene tetracarboxylic derivatives as semiconducting materials.
Zhao, Xizhe, "Mild Synthesis of Perylene Tetracarboxylic Monoanhydrides with Potential Applications in Organic Optoelectronics" (2019). CUNY Academic Works.