Synthesis and characterization of metal complexes supported by bis (arylimino) acenaphthene

• Main Author: Wang, Jingyi
• Other Authors: Felipe García
• Format: Theses and Dissertations
• Language: English
• Published: 2018
• Subjects: DRNTU::Science::Chemistry
• Online Access: http://hdl.handle.net/10356/74144
• Institution: Nanyang Technological University

Although bis(arylimino)acenaphthene (Ar-BIAN) ligands have been recognized as robust ligands for metal complexes since the early 2000, most of its coordination chemistry was focused on transition metals with relatively little attention being paid to main group elements. In particular, the physicochemical properties of Ar-BIAN complexes, which is of interest to our group, still remain un-explored. On the other hand, in view of the growing interest in greener synthetic methods, solid state syntheses have become especially appealing to synthetic chemists. However, reports on mechanochemistry in molecular compounds, especially main group complexes, have been scarce, despite its appeal as a low-solvent, low-energy, and potentially atom-efficient synthetic method. In this thesis, firstly, a mechanochemical grinding approach to the synthesis of Ar-BIAN ligands and its coordination complexes with heavy p-block element, indium, will be introduced (chapter 2). The atom-efficient, less time consuming, and low solvent aspects associated with this method will be highlighted. This is then followed by a more comprehensive description on the syntheses of a range of indium(III) Ar-BIAN complexes bearing different substituents at the aryl-diimine moiety (chapter 3). This chapter also concerns a systematic investigation on the optical and electrochemical properties of the as synthesized indium(III) Ar-BIAN complexes with the intention to explore their potential application as photosensitizers, and the effect of functionalization of the aryl-diimine moiety on such properties. In chapter 4, a modified Ar-BIAN ligand design which includes an electron withdrawing group on the acenaphthene backbone will be presented. Besides, an improvement on the photoexcited lifetime of an iridium(III) complex bearing the modified Ar-BIAN ligand will be demonstrated using both steady state and time resolved spectroscopic measurements.