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The structure and properties of a new semiconducting BEDT-TTF-based charge-transfer salt containing the magnetic monoanion octamethylferrocenedisulfonate (–O3SC5( CH3)4Fe+C5(CH3)4-SO3 – (ofds)), -(BEDT-TTF)5(ofds)2 is described (BEDT-TTF = bis(ethylenedithio)tetrathiafulvalene). The salt is a semiconductor with RT = 5.6  103 ·cm and Ea = 0.11 eV. There are two types of spins not only on the ferrocenyl parts but also the 2D donor layers. The former and latter spins obey Curie-Weiss (C = 0.721 emu K mol-1and  = -5.5 K) and 2D Heisenberg (J2DH = - 80.3 K) models, respectively.

Radical-cation salts of BEDT-TTF with chiral anions provide the opportunity to combine chirality with conductivity in the same molecular material. We report here two salts, (BEDT-TTF)3NaAl(C2O4)3·nitromethane and (BEDT-TTF)3(NH4)0.83Cr1.17(C2O4)3·nitromethane. The former crystallises in space group P21 and the latter in P212121. The use of nitromethane alone as the electrolyte for electrocrystallisation produces no crystals, but the addition of chiral (R)-(–)-carvone yields crystals of these two new chiral radical-cation salts of BEDT-TTF through chiral induction from racemic tris(oxalato)aluminate(III) and tris(oxalato)chromate starting materials. The honeycomb anion layers in these salts contain a single enantiomer of tris(oxalato)metallate and creates hexagonal cavities that are smaller than those found in the superconducting β″ salts in this tris(oxalate)metallate family, which gives preference for smaller solvents to be included, such as nitromethane. The chromium salt has a non-stoichiometric composition of the anion layer, which provides an electron doping effect to the donor layer.

A series of aryl-substituted naphthalenediimide derivatives that contain nitroxide radicals were prepared and their crystal structures were elucidated. Much stronger charge-transfer interactions were present in the derivatives with perfluorobenzene substituents than those with phenyl or 4-fluorophenyl substituents. These interactions result in the formation of single-component charge-transfer complexes by self-assembly of the naphthalenediimide derivatives to provide black crystals. As a consequence, the naphthalenediimide derivatives with perfluorobenzene substituents have better field-effect transistor (FET) properties than the other derivatives.

Oxidation of ortho-alkenyl N-substituted benzamides with hypervalent iodine compounds is described to yield isochroman-1-imines.

Series of organic biradical compounds 3a–3h consisting of a mesogenic core (biphenyl, naphthalene, azobenzene and azoxybenzene) and long alkoxy groups with PROXYL or TEMPO radicals were prepared. The TEMPO derivatives (3b, 3d, 3f, and 3h) were found to show fairly large antiferromagnetic interactions (J = −34 ∼ −45 K) being well expressed by singlet-triplet model irrespective of the mesogenic cores and the behavior is understandable by taking a hand-in-hand like assembled structure into consideration. On the other hand, only weak antiferromagnetic interactions with Curie–Weiss behavior were observed in all of the PROXYL derivatives (3a, 3c, 3e, and 3d) affording a sharp contrast with the TEMPO-based biradicals. Copyright © 2006 John Wiley & Sons, Ltd.

The synthesis and structural characterization of new liquid-crystalline compounds containing ferrocene, azo-aromatic and cholesteryl groups are reported. Taking into account the advantage brought by chirality, ferrocene and azo units, these structures could be good precursors for obtaining materials capable of responding to magnetic and electric fields or to UV-light exposure. The influence of each structural unit (ferrocene, cholesterol, azo aromatic core and flexible chain length) has been studied by comparing analogous compounds possessing the same structure but without the element being analyzed. Ferrocene is a three-dimensional bulky unit, so that, regardless of the substituents' nature, this unit could cause steric repulsions with neighboring molecules. These interactions could lead to a decrease of the transition temperature domain. Surprisingly, a decrease in the clearing point was not observed for the compounds discussed. This behavior was possible because ferrocene is connected to the mesogen via a flexible unit. As a consequence, both phenyl analogues and ferrocene derivatives presented liquid-crystalline properties with similarly high clearing points, but above the thermal stability of derivatives with azo groups. Their melting points depend on the way the molecules are packed, with different crystalline states being detected in the case of ferrocene derivatives. In order to explain the liquid-crystalline behavior of the compounds synthesized, molecular simulations were performed using the Hyperchem program. Copyright © 2005 John Wiley & Sons, Ltd.

A couple of naphthalenediimide derivatives carrying TEMPO radicals were found to exhibit n-type FET with mobilities up to 2.6×10−5 cm2/V·s as the first examples of spin-carrying acceptor systems wh...

The synthesis of DHOT-TTP, in which one sulfur atom of BDH-TTP [2,5-bis(1,3-dithiolan-2-ylidene)-1,3,4,6-tetrathiapentalene] is substituted by oxygen, has been accomplished. The DHOT-TTP donor possesses a less planar molecular structure than BDH-TTP, and gives a metallic AuI 2 salt stable down to 1.4 K, the crystal structure of which is elucidated.

The preparation, crystal structure and physical properties of β-(BDA-TTP)2GaCl4 has been investigated; the salt exhibits superconductivity at 3.1 K (onset) under a hydrostatic pressure of 7.6 kbar.

The synthesis and electrochemical properties of the DHDA-TTP donor, a hybrid of 2,5-bis(1,3-dithiolan-2-ylidene)-1,3,4,6-tetrathiapentalene (BDH-TTP) and 2,5-bis(1,3-dithian-2-ylidene)-1,3,4,6-tetrathiapentalene (BDA-TTP), has been investigated, and its ability to form metallic cation-radical salts is elucidated.

Several organic spin systems based on 4-(N-alkyl)amino-TEMPO (TEMPO = 2,2,6,6-tetramethylpiperidinyl-1-oxy) radicals were prepared in which cholesterol or biphenyl mesogenic cores with long alkyl or alkoxy substituents were incorporated in order to investigate the possible occurrence of liquid crystalline properties. Of these radicals a lamellar structure was found in a biphenyl derivative with the 4-(N-methyl)amino-TEMPO-substituent 13; this compound showed mesogenic properties. The local antiferromagnetic spin interactions based on a singlet-triplet model observed during the heating process in the radical were found to turn to a Curie−Weiss behavior after the thermal transition during the cooling process. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)