Salts of extended tetrathiafulvalene analogues: relationships between molecular structure, electrochemical properties and solid state organisation

Decorating tetrathiafulvalene (TTF) with fluorinated phenyls through sulfur bridges: facile synthesis, properties, and aggregation through fluorine interactions

Tetrathiafulvalene derivatives (TTF1-TTF9) bearing fluorinated phenyl groups attached through the sulfur bridges have been synthesized by employing a copper-mediated C-S coupling reaction of C6 H5-x Fx I (x=1, 2, 5) and a zinc-thiolate complex, (TBA)2 [Zn(DMIT)2 ] (TBA=tetrabutyl ammonium, DMIT=1,3-dithiole-2-thione-4,5-dithiolate), as the key step. Particularly, the selective synthesis of C6 F5 -substituted (TTF8) and C6 F4 -fused (TTF9) TTFs from C6 F5 I is disclosed. The physicochemical properties and crystal structures of these TTFs are fully investigated by UV/Vis absorption spectra, cyclic voltammetry, molecular orbital calculation, and single-crystal X-ray diffraction. The exchange of hydrogen versus fluorine on the peripheral phenyl groups show a notable influence on both the electronic and crystallographic natures of the resulting TTFs: 1) lowering both the HOMO and the LUMO energy levels, 2) modulating the electrochemical properties by regioselective and/or the degree of fluorination, 3) enhancing the driving forces of stacking by multiple fluorine interactions (F⋅⋅⋅S, CF⋅⋅⋅π/πF , CF⋅⋅⋅FC, and CF⋅⋅⋅H). This work indicates that the decoration with fluorinated phenyls holds promise to produce functional TTFs with novel electronic and aggregation features.

New unsymmetrically benzene-fused bis (tetrathiafulvalene): synthesis, characterization, electrochemical properties and electrical conductivity of their materials

The synthesis of new unsymmetrically benzene-fused bis (tetrathiafulvalene) has been carried out by a cross-coupling reaction of the respective 4,5-dialkyl-1,3-dithiole-2-selenone 6-9 with 2-(4-(p-nitrophenyl)-1,3-dithiole-2-ylidene)-1,3,5,7-tetrathia-s-indacene-6-one 5 prepared by olefination of 4-(p-nitrophenyl)-1,3-dithiole-2-selenone 3 and 1,3,5,7-tetrathia-s-indacene-2,6-dione 4. The conversion of the nitro moiety 10a-d to amino 11a-d then dibenzylamine 12a-d groups respectively used reduction and alkylation methods. The electron donor ability of these new compounds has been measured by cyclic voltammetry (CV) technique. Charge transfer complexes with tetracyanoquino-dimethane (TCNQ) were prepared by chemical redox reactions. The complexes have been proven to give conducting materials.

Synthesis of pyrrolidine-fused 1,3-dithiolane oligomers by the cycloaddition of polycyclic dithiolethiones to maleimides and evaluation as mercury(II) indicators

The scandium triflate-catalyzed cycloaddition reaction of polycyclic 1,2-dithiolethiones to maleimides is described. The reaction constitutes an easy approach to linear as well as branched oligomeric cis-fused dihydro[1,3]dithiolo[4,5-c]pyrrole-4,6-dione rings interconnected by 3,5-diylidenethiomorpholine-2,6-dithione or ylidene-6-thioxo[1,2]dithiolo[3,4-b][1,4]thiazin-3-one groups. The presence of highly colored, highly polarized push-pull α,β-unsaturated thione groups in their structures make these compounds sensitive to the presence of mercury(II) cation in organic or mixed organic/aqueous solvents.

Tetrathiafulvalene-capped hybrid materials for the optical detection of explosives

Mesoporous silica microparticles capped with TTF moieties and containing a ruthenium dye in the pores were used for the turn-on optical detection of the nitroaromatic explosives Tetryl and TNT via a selective pore uncapping and release of the entrapped dye.

Hybrid super electron donors - preparation and reactivity

Neutral organic electron donors, featuring pyridinylidene–imidazolylidene, pyridinylidene–benzimidazolylidene and imidazolylidene–benzimidazolylidene linkages are reported. The pyridinylidene–benzimidazolylidene and imidazolylidene–benzimidazolylidene hybrid systems were designed to be the first super electron donors to convert iodoarenes to aryl radicals at room temperature, and indeed both show evidence for significant aryl radical formation at room temperature. The stronger pyridinylidene–imidazolylidene donor converts iodoarenes to aryl anions efficiently under appropriate conditions (3 equiv of donor). The presence of excess sodium hydride base has a very important and selective effect on some of these electron-transfer reactions, and a rationale for this is proposed.

Fragmentations observed in the reactions of α-methoxy-γ-alkoxyalkyl iodide substrates with super-electron-donors derived from 4-DMAP and N-methylbenzimidazole

Reactions of super-electron-donors (SEDs) derived from 4-dimethylaminopyridine and from N-methylbenzimidazole with α-methoxy-γ-alkoxyalkyl iodides lead to liberation of the γ-alkoxy groups as their alcohols. This is consistent with generation of alkyl radicals from the alkyl halide precursors, and trapping of these radicals by the radical-cation of the SED, followed by a heterolytic fragmentation.