Robert R. Schumaker

Synthesis and properties of tetrathiafulvalene–metal bisdithiolene macromolecules

Reaction of tetrasodium tetrathiafulvalene-tetrathiolate with transition metal salts leads to the formation of tetrathiafulvalene-metal bisdithiolene oligomers which in the case of the nickel derivative possesses unusually high conductivity (ca. 30 Ω–1 cm–1).

Chemistry of geminal-dithiolates derived from cyano-substituted tetrathiafulvalenes

Tetracyanotetrathiafulvalene reacts with two equivalents of thiol salts (RS−) to give 1,2-dicyano-1,2-di RS ethene and a geminal dithiolate intermediate which reacts with a variety of reagents to provide novel tetrathioethene derivatives, such as reaction with 3-chloro-2-butanone and acid to give dimethyldicyanotetrathiafulvalene.

RADIKALIONEN 65.1 IONISATION UND OXIDATION VON TETRATHIAFULVALEN-DERIVATEN

Abstract Photoelectron spectra of tetrathiafulvalene derivatives with substituents R=CH3, SCH3, H, Br, CF3 and CN as well as electron spin resonance spectra of their radical cations, generated with AlCl3 in H2CCl2, have been recorded. The PES and ESR/ENDOR data, supplemented by literature values and based on MNDO and PAROP-MO calculations, are comprehensively discussed as substituent effects on the tetrathiafulvalene π system. To interpret the various measurements, the easily accessible PAR ameter OP timized MO results prove to be especially useful, because their correlations with experimental data yield reliable estimates of the ionization energies, the half-wave oxidation potentials and the radical cation coupling constants of sulfur-containing π systems. Von Tetrathiafulvalen-Derivaten mit Substituenten R[dbnd]CH3, SCH3, H, Br, CF3 und CN wurden Photoelektronen-Spektren und von ihren mit AlCl3 in H2CCl2 erzeugten Radikalkationen Elektronen-spinresonanz-Spektren aufgenommen. Die PES- und ESR/ENDOR-Mesda...

‘Organic metals’: synthesis of dithiolylidenetetrathiapentalenones and their higher analogues

Reaction of the tetrathiapentalene-2,5-dione (1) and 4,5-dimethoxycarbonyl-1,3-dithiole-2-thione (2) with trimethylphosphite in refluxing benzene provides, along with the expected self-coupled products, the dithiolylidenetetrathiapentalenone (4; R = CO2Me) and its higher analogue (6; R = CO2Me).

Triselenathiafulvalenes: a novel sulphur–selenium interchange on trimethyl phosphite coupling of substituted 1,3-diselenole-2-thiones

Coupling using trimethyl phosphite of 4,5-dimethoxycarbonyl- and 4,5-ditrifluoromethyl-1,3-diselenole-2-thiones unexpectedly gave only tetramethoxycarbonyl- and tetratrifluoromethyl-triselenathiafulvalene respectively, while self-coupling of 4,5-dimethyl-1,3-diselenole-2-thione provided a mixture (85:15) of tetramethyltetraselenafulvalene and tetramethyltriselenathiafulvalene.

Novel bonding geometry and valence tautomerism of 4-(N,N-dimethyldithiocarbamato)-2-dimethyliminio-1,3-dithietane tetraphenylborate, [Me2NCS2·CH·S2CNMe2]+Ph4B–

A ring-opening/ring-closing tautomerism in solution of the title compound is deduced from the temperature dependence of the 1H NMR spectra; the molecular structure found by X-ray crystal analysis is favourably oriented for this tautomerism.

THIAPEN CHEMISTRY: CAPPING REACTIONS OF THIAPENDIONE

Abstract Considerable interest has been shown in the chemistry of tetrathiafulvalene (TTF, 1) since some of these π-donors react with acceptors to form the most conducting organic solids presently known. The recent synthesis of thiapendione (2) provided the possibility of elaborating a wide variety of novel TTF derivatives through cross-coupling reactions with 1,3-dithioles (3) using trimethyl phosphite. The capping reaction is very dependent on the nature of the R and X substituents in 3, and succeeds for R=CN, X=0 or R= CO2Me, CF3, X[dbnd]S to give mono- and bis-capped products 4 and 5.

New Directions in Organic Electronic Materials Based on Tetrathiafulvalene

Widespread interest has been shown recently in the chemistry1 and physics2 of charge-transfer salts based on the organic π-donor, tetrathiafulvalene (TTF) since some of these materials were found to display unusual metal-like properties. This paper will describe two approaches that we have taken for preparing new organic electronic materials based on some of the insights and understanding gained from studying TTF. The first approach is essentially synthetic in orientation, and involves the preparation of extended π-systems based on the TTF ring system. The second approach involves the study of electron transport in less ordered systems, namely polymeric materials in which TTF has been incorporated as a pendant group.