Design, Synthesis, And Properties Of Tetrathiafulvalene (TTF) Derivatives With Novel Assembly Nature

Tetrathiafulvalene, abbreviated as TTF, is a well-down organic donor and possesses two reversible one-electron redox waves. Since synthesized in the early1970s, TTF and its derivatives have been intensively studied as the key conduction components for organic conductors/superconductors. With the development of the supramolecular chemistry as well as molecular electronics, TTF framework has recently been employed as the active building blocks for molecular devices such as organic field effective transistor, chemosenor, catenane, and so on.This originates from the unique electrochemical behavior and tight assembly in solid state of TTF unit, and these features can be finely tuned by means of chemical modification, In the present thesis, we focus on the application of TTF derivatives in the supramolecular system. The main subject of this thesis is the design, synthesis, and electrochemical and optical properties of bis-TTFs with the flexible spacer connecting two units.In Chapter1, we made the brief introduction about the structural feature of TTF framework along with the influence of chemical modification on the spatial aligments and electronic structures of resulting TTFs. Then we summarized the application of TTF derivatives in organic conducting materials and supramolecular system, mainly focus on the construction of bis-TTFs and the metal-organic frameworks (MOFs). Finally, we outlined the design rationale and contents of this thesis.In Chapter2, we reported the design and synthesis of flexible σ-bond connected bis-TTF. The key step for the synthesis of these molecules is the Cu-catalyzed C-S coupling between aryl halides and (TBA)2[Zn(DMIT)2] developed by our group very recently. Four new σ-bond connected bis-TTFs(1,2,3,4) incorporated with aryl on the peripheral positions were created. Needless to say, the functional groups on the aryls in3and4would provide the further opportunity for coordination with transition metals. The aryl-fused bis-TTFs,1and2, show three reversible redox waves. The former two belongs to the one-electron oxidation and the latter one is a two-electron oxidation state. However, the aryl-substituted bis-TTFs,3and4, show two reversible redox waves both belonging to the two-electron oxidation state. These bis-TTFs display the broad absorption band in the visible region ascribable to the extention of π-conjugation by the aromatic substituents.In Chapter3, we disclosed the facile and highly efficient elimination reaction of2-bromoethyl substituted TTF derivatives, which afford the vinyl substituted TTFs. We have optimized the reaction conditions of this reaction by screening the catalysts and alkalis. By using the vinyl substituted TTF as starting material, we have synthesized a new TTF derivative (29) through the typical Diels-Alder reaction. The further investigation will be directed to the creation of the bis-TTFs and/or tris-TTFs.In Chapter4, we reported the preliminary investigation on the exploration of TTF derivatives having coordination capability. Up to date, we have synthesized compound36incorporated with salicyaldehyde. In the successive study, we will use36to synthesize TTFs having functional groups such as schiff base and/or1,3-diketal. Consequently, we will prepare the coordination complexes of the TTFs with transition metals to achieve the MOFs.