Synthesis, Structure And Properties Of Multi-sulfur Electronic Donor BVDT-TTP And BVDT-TTPY

In the early 1970s,the multi-sulfur electronic donor TTF(Tetrathia-fulvalene, C₆S₄H₄)came into being as the most famous electronic donor in the area of molecular conductors.Ten years later,the number of sulfur atom in the TTFs electronic donor had been added to eight,for example,the best electronic donor in the area of molecular superconductors,the BEDT-TTF(Bis(4,5-ethylenedithio)tetrathiafulvalene,C₁₀S₈H₈).Recently,the multi-sulfur electronic donors with TTP(tetrathiapentalene)moity are a new enlargement of the TTFs.Its sulfurs number had been farther expanded,the molecular planarity and theÏ€-conjugation been much improved.At the same time,the synthesis became more and more difficult,for example,the steps had to be increased and the solubility of the resultant compounds reduced sharply.The main goal of this thesis is to synthesize the new multi-sulfur electronic donor with 12 or 16 sulfur atoms,to blaze a way in the development of new molecular conductors and molecular superconductors.We started from the CS₂ with 2 sulfurs,and enlarged the molecular dimension step by step,harvested many intermediae compounds, carried through large mumber of experiments to explore the reaction conditions(for example,the conditions of coupling reaction),and finally we successfully synthezied our target electronic donor BVDT-TTP with 12 sulfur atoms and further more the BVDT-TTPY with 16 sulfur atoms.1.Firstly,we synthesized the electronic donor BVDT-TTP with 12 sulfur atoms.2,5-bis(4,5-vinylenedithio-1,3-dithio-2-ylidene)-1,3,4,6-tetrathiapentalene we firstly determined the molecular strcture and crystal structure of BVDT-TTP.The BVDT-TTP molecular with the length of 18.6 nm is almost planar,except that the vinylenes on the two ends tilt from the plane.The other 22 atoms are in the same plane. The planarity andÏ€-conjugation make theÏ€-electrons delocalized on whole molecules. All of molucules in the crystal accumulate are parallely packed,the distance between two molucules is 0.3578 nm.There is quite strongÏ€-Ï€interaction between neighbouring molucules,it is good for electrons to move. 2.We firstly synthesized the electronic donor BVDT-TTPY with 16 sulfur atoms.2,2'-bis[4,5-vinylenedithio-(1,3-dithio-2-ylidene)-1,3,4,6-tetrathiapentaleneylidene]3.We firstly determined the molecular strcture and crystal structure of VDTO-TTP,the direct precursor of BVDT-TTP and BVDT-TTPY.