New substrates for the preparation of electroactive materials: the syntheses of chiral tetrathiafulvalene derivatives with hydroxy-functionalised butane-1,4-dithio bridges

The syntheses of two derivatives of TTF containing (2R,3R)-2,3-dihydroxybutane-1,4-dithio bridges is described, for use in the preparation of chiral hydrogen bonded radical cation salts as potentially electroactive materials. The bridges are introduced by reaction of 2-thioxo-1,3-dithiole-4,5-dithiolate with 1,4-disubstituted derivatives of bis-O-protected butane-2,3-diol to give a bicyclic thione. The X-ray crystal structure of the isopropylidene ketal derivative shows that all four sp(3) carbon atoms in the eight-membered ring are displaced to the same side of the dithiole plane. Ease of deprotection led to the use of methoxyethoxymethyl (MEM) protecting groups rather than the ketal. Treatment of the bis-MEM-protected bicyclic thione with mercuric acetate and acetic acid led not only to exchange of the exocyclic sulfur for oxygen but also to removal of just one of the MEM groups, which may have wider synthetic applications

Synthesis and Materials Chemistry of Bismuth <i>Tris</i>-(di-i-propylcarbamate): Deposition of Photoactive Bi₂O₃ Thin Films

The bismuth carbamate Bi­(O₂CNPrⁱ₂)₃, a tetramer in the solid-state, has been synthesized and used to deposit mixtures of bismuth oxides by aerosol-assisted chemical vapor deposition (AACVD). The nature of the deposited oxide is a function of both temperature and run-time. Initially, δ-Bi₂O₃ is deposited, over which grows a thick layer of β-Bi₂O₃ nanowires, the latter having an increasing degree of preferred orientation at higher deposition temperatures. The photocatalytic activity of a thin film of δ-Bi₂O₃ for the degradation of methylene blue dye was found to be similar to that of a commercial TiO₂ film on glass, while the film overcoated with β-Bi₂O₃ nanowires was less active. Exposure of Bi­(O₂CNPrⁱ₂)₃ to controlled amounts of moist air affords the novel oxo-cluster Bi₈(O)₆(O₂CNPrⁱ₂)₁₂, whose structure has also been determined