THE SYNTHESIS OF DERIVATIVES OF 1,3-DITHIEPIN CONTAINING THE TETRATHIOETHYLENE UNIT AND A BRIEF EXPLORATION OF THEIR COORDINATION CHEMISTRY (DITHIOLATE, THIOETHER)

This research has centered on the design, synthesis, chemical reactivity and physical and structural studies of a new class of organ- osulfur compounds and their selected transition metal complexes. This work exemplifies efforts to unite the research efforts of both the organic and inorganic chemist into a new direction of studies of low dimensional conducting materials. These new organosulfur com-; pounds are based on the 1,3-dithiepin-2-carbodithiolate intermediate, which contains the tetrathioethylene unit and is shown below.; (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI); Selected transition metal complexes of this intermediate and its derivatives have been prepared. Nuclear magnetic resonance, elec- tron spin resonance, optical spectroscopy, molecular orbital calcu- lations, cyclic voltammetry and single crystal x-ray analysis studies have been utilized to characterize the electronic properties of all compounds.; The organosulfur compounds are all new examples of compounds which contain the tetrathioethylene unit. Electrochemically these compounds differ dramatically from previously reported TTF type compounds. Their chemical instability to oxidation is explained using resonance and extended Huckel methods.; The metal complexes of DTDC('2-) are the first examples of 1,1-dithiolate metal complexes which contain the tetrathioethylene unit. Surprisingly, these compounds isolated as tetraethylammonium salts are both air and moisture stable. ('1)H NMR and ESR studies show these complexes to be highly delocalized in nature. This is not the case in the metal complexes formed from the alkyl derivatives of (DTDC('2-)).; The coordination complexes of the neutral ligands are bidentate in nature as opposed to an anticipated cocrystallized complex. Gross geometry around the metal center is square planar. Coordination to the metal has only a minor effect on most physical properties, except the electrochemistry. In this case coordination of the metal stabilizes the system towards oxidation.