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The titled tetracyanodiphenoquinodimethane (TCNDQ) derivative was newly designed and prepared as a novel component for highly conductive organic materials. Introduction of 1,2,5-thiadiazole rings into the TCNDQ skeleton leads to large stabilization in the neutral state. X-ray analysis has revealed their structural details which suggest that interatomic interactions (CH…N, S…N) play an important role in determining the molecular and crystal structure. The novel electron acceptor shows strong electron affinity comparable with that of TCNQ, and gave highly conductive charge-transfer (CT) complexes and an anion radical salt.

Novel indenofluorenedione and diindenopyrazinedione derivatives were developed as n-type semiconductors. Introduction of the halogen goups and/or a pyrazine ring to the indenofluorenedione framework increased the electron affinity, leading to the higher n-type performances. The top-contact device using 2b showed the highest performance; µ = 0.17 cm2/(V s) and Vth = 17 V.

Charge-transfer salts between BDNT and M(mnt)2 (M=Ni, Pd, Pt, and Au) have been prepared by mixing BDNT–(SbCl6)2 and (TBA)2 –[M(mnt)2 ] and by electrochemical oxidation of BDNT in TBA–[M(mnt)2 ] solution. Almost all powdery samples of (1:1) salts show high electrical conductivity. The valence of M(mnt)2 was determined to be –1 by the CN stretching mode, which means that the valence of BDNT is +0.5, +1, or +2. Their crystal structures are not known except for the low-conductive BDNT–[Au(mnt)2 ]2 , in which Au(mnt)2 forms dimers which are arranged in crisscross stacks. Among these compounds, (BDNT)2–[Ni(mnt)2 ] exhibits a ferromagnetic interaction with |J|=3.4 K. It is concluded from the EPR experiment that [Ni(mnt)2 ]– is responsible for the ferromagnetic interaction.

Benzo[1,2-c:4,5-c′]bis([1,2,5]thiadiazole) containing a hypervalent sulfur atom has a low LUMO energy. The aryl derivatives were synthesized using a Stille coupling reaction. The selenadiazole analogues were also prepared. The electron accepting properties of these nonclassical heterocycles were shown by their high reduction potentials. Introduction of electron-donating groups into the electron-withdrawing heterocycles afforded novel donor-acceptor compounds. Their cyclic voltammograms showed that they are easily both oxidized and reduced. Some of them have the absorption maxima above 700 nm due to the small HOMO-LUMO separation. X-ray structure analysis of the diphenyl derivative revealed the formation of a tape-like network through short S⋯N contacts. © 1997 Elsevier Science Ltd.

We have prepared the cation radical salts based on a nonplanar donor 4,11-bis(4′,5′-ethylenedithio-1′,3′-dithiole-2′-ylidene)-4,11-dihydroanthra[2,3-c] [1,2,5] thiadiazole (BEDT-ATD), (BEDT-ATD)2X(Solvent) (X˭PF6, BF4; Solvent=THF, DHF (2,5-dihydrofuran)). The band structure of a stable organic metal (BEDT-ATD)2PF6(THF) is presented. The replacement of an anion or a solvent molecule has induced a metal-insulator transition at 200 K and 150 K for (BEDT-ATD)2BF4(THF) and (BEDT-ATD)2PF6(DHF), respectively.

The title compounds were designed as novel electron acceptors and prepared from 4,7-dihalobenzo[1,2,5]chalcogenadiazoles in two steps. Comparisons of X-ray structures indicate that the packing arrangements of the different chalcogenadiazole derivatives are quite different from each other in spite of their similar molecular geometries. In the crystal of the selenadiazole derivative (3) are observed very short intermolecular contacts between Se and N to form infinite “sheet”-like network, whereas coplanar dyads are formed by C-H…N≡C hydrogen bonds in the oxadiazole (1) and thiadiazole derivatives (2). These acceptors afforded stable anion-radical salts upon one-electron reduction and gave highly conductive charge-transfer complexes with tetrathiafulvalene derivatives.

The dibromodihydrodipyrrin diester 7 was prepared by reaction of the corresponding pyrrole 6 with dimethoxymethane and BF3·Et2O. Subsequently 7 was converted into the dibromodihydrodipyrrin 2 in moderate yield. The diformyldihydrodipyrrin 3 was readily prepared by methylenation of the pyrrole 9 with BF3·Et2O, followed by deprotection. Attempted synthesis of the porphyrin 1 from 2 and 3 was unsuccessful because of the low reactivity of 2. The reaction of 7 or 11 with hexabutylditin in the presence of a Pd catalyst produced a new type of tin complex 12 in low yield. This complex was also readily obtained by an alternative procedure and found to revert to 7 upon reaction with TFA.

Tailoring the surface of biometallic implants with protein-resistant polymer brushes represents an efficient approach to improve the biocompability and mechanical compliance with soft human tissues. A general approach utilizing electropolymerization to form initiating group (-Br) containing poly(3,4-ethylenedioxythiophen)s (poly(EDOT)s) is described. After the conducting polymer is deposited, neutral poly((oligo(ethylene glycol) methacrylate), poly(OEGMA), and zwitterionic poly([2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide), poly(SBMA), brushes are grafted by surface-initiated atom transfer radical polymerization. Quartz crystal microbalance (QCM) experiments confirm protein resistance of poly(OEGMA) and poly(SBMA)-grafted poly(EDOT)s. The protein binding properties of the surface are modulated by the density of polymer brushes, which is controlled by the feed content of initiator-containing monomer (EDOT-Br) in the monomer mixture solution for electropolymerization. Furthermore, these polymer-grafted poly(EDOT)s also prevent cells to adhere on the surface.

The monoclinic form of BDNT-PF6 (m-BDNT-PF6) is characterized as a pseudo-one-dimensional half-filled Hubbard system from the electrical conductivity, magnetic susceptibility, and single crystal optical spectra. m-BDNT-PF6 undergoes a spin-Peierls transition at about 150 K. The lattice dimerization was confirmed by the evolution of the vibronic modes at low temperature. The small polaron binding energy of this compound, which was estimated through the analysis of the vibronic modes, is smaller than those of TTF, TCNQ, or CA. Hubbard parameters U and t were obtained to be 0.8 and 0.13eV by analyzing the charge-transfer band. The optical and magnetic data are consistent with each other. Die monokline Form von BDNT-PF6 (m-BDNT-PF6) wird auf Gund von Messungen der elektrischen Leitfahigkeit, magnetischen Suszeptibilitat und optischen Einkristallspektren als pseudoein-dimensionales halbgefulltes Hubbard-System charakterisiert. m-BDNT-PF6 erfahrt einen Spin-Peierls-ubergang bei etwa 150 K. Die Gitterdimerisation wurde durch die Entwicklung der Schwingungsmoden bei niedriger Temperatur bestatigt. Die geringe Polaron-Bindungsenergie dieser Verbindung, die durch Analyse der Schwingungsmoden abgeschatzt wurde, ist kleiner als bei TTF, TCNQ oder CA. Die Hubbard-Parameter U und t wurden mittels Analyse des Ladungstransferbandes mit 0,8 und 0,13 eV bestimmt. Optische und magnetische Daten stimmen miteinander uberein.

The neutral molecule, monocation, and dication of BDNT, which shows a one-step two-electron oxidation property, were characterized by a spectroscopic method. The extreme closeness of the first and second oxidation potentials is ascribable to the large structural change from BDNT1+ to BDNT2+. The on-site Coulomb energy U and transfer integral t of monoclinic BDNT-PF6 were estimated to be 0.8 eV and 0.13 eV, respectively. The coupling constants of the vibronic band were estimated by the least-squares fitting of the dimer-model function to the observed conductivity spectrum. These coupling constants shows that BDNT1+ is rather rigid compared with TTF, TCNQ, or Chloranil.

The cation radical salts with a new electron donor 4,11-bis(4′,5′-ethylenedithio-1′,3′-dithiol-2′-ylidene)-4,11-dihydroanthra[2,3- c ] [1,2,5]thiadiazole (BEDT-ATD) have been prepared by an electrochemical oxidation in tetrahydrofuran (THF). The salts with PF 6 − and AsF 6 − anions were obtained as (BEDT-ATD) 2 X(THF) (X = PF 6 , AsF 6 ). The electrical resistivities at room temperature were 0.04 and 0.02 Ω cm for the PF 6 salt and the AsF 6 salt, respectively. Both salts showed a metal-like behavior in the electrical conduction. The spin susceptibility revealed a Pauli paramagnetism down to 3 K, indicating a metallic state. A semiconducting phase appeared by applying pressure above 2.5 kbar.

In the crystal structure of the title compound, 5-(4,5-di­iodo-1,3-di­thiol-2-yl­idene)-1,3-di­aza-2,4,6-tri­thia­pentalene, C6I2N2S5, a large number of short intermolecular heteroatom contacts, such as S⋯N, S⋯S, S⋯I, N⋯I and I⋯I, are observed. The mol­ecules, which are planar within 0.051 A, stack along the b axis in a head-to-head fashion.

In the crystal structure of the title compound, C6H2N2S2, there is a tape structure, as a result of C—H⋯N hydrogen bonds is found. The mol­ecules stack along the [120] direction in a head-to-tail fashion.

A tetracyanodiphenoquinodimethane (TCNDQ) analog containing fused thiadiazole rings is a stronger electron acceptor than tetracyanoquinodimethane (TCNQ). The single crystals of this TCNDQ analog were found to exhibit semiconductive behaviors as a single component whose structures were revealed by X-ray structure analysis. The anion radical salts with Et4N and Me4P ions were obtained as single crystals by electrochemical reduction. They are 1:1 salts and showed semiconductive behaviors. The structures include tape-like networks formed by S–N contacts. Furthermore, one of the benzothiadiazole rings was replaced with a thiophene unit to give new π-extended quinonoid acceptors which are highly polarized and exhibit their absorption maxima above 500 nm.

In the crystal structure of the title compound, 4,5-ethyl­ene­dioxy­[1,2,5]­thia­diazo­lotetra­thia­fulvalene, C8H4N2O2S5, a large number of short intermolecular S⋯S contacts are observed. The mol­ecules stack along the c axis in a face-to-face fashion.

11,11,12,12-Tetracyano-9,10-anthraquinodimethane (TCNAQ) derivatives having four types of aryl substituents, phenyl, biphenyl-4-yl, thien-2-yl, and 2,2′-bithiophen-5-yl groups at their 2-position, ...

π-Conjugated systems 2a and 2b containing thiophene-fused DCNQI with long alkyl and trifluoromethylphenyl groups were synthesized as potential active materials for solution-processed and air-stable n-type organic thin-film transistors (OTFTs). The electrochemical measurements revealed that the lowest unoccupied molecular orbital (LUMO) of the compounds have an energy level less than -4.0 eV, indicating air stable n-type materials. The long alkyl groups endowed the compounds good solubility and solution-processability. X-ray diffraction measurements revealed the difference of the molecular arrangement depending on the alkyl groups, which were also observed in the UV-vis absorptions of the films. A relatively good mobility up to 0.003 cm(2) V(-1) s(-1) for 2a by spin-coating was obtained with good air stability.

By treating compound (V) with a bisboronic acid derivative it is possible to obtain a polymeric structure.

Two new compounds, 3,6-bis(4-trifluoromethylphenyl)thieno[3,2-b]thiophene-2,5-dione (1) and 2,5-bis(dicyanomethylene)-3,6-bis(4-trifluoromethylphenyl)thieno[3,2-b]thiophene (2), were synthesized an...

Novel dithiolato-metal complexes from 2,3-dicyano-5,6-dimercaptopyrazine (H2dcdmp) ligands have been synthesized, and their TTF salts, (TTF),[M(dcdmp)2]2 (MNi or Pd)i, have been obtained by the diffusion method in acetonitrile. The electrical conductivities of these complexes at room temperature are between 10−2 and 10−3 S cm−1. The X-ray structural analysis of (TTF)5[Pd(dcdmp)2]2 indicates that two Pd(dcdmp)2 molecules and one TTF molecule from 2:1 mixed stacks along the c axis, and other TTF molecules stack along the b axis. A number of intermolecular S···N and S···S heteroatom contacts within the sum of van der Waals radii are observed in the crystals.

Angle‐resolved ultraviolet photoemission spectra using synchrotron radiation were measured for oriented thin films of bis(1,2,5‐thiadiazolo)‐p‐quinobis(1,3‐dithiole) (BTQBT) on graphite. From the photon energy dependence of normal emission spectra, the energy‐band dispersion of π‐bands were observed for the highest (HOMO) and next highest (NHOMO) bands. This is the first observation of intermolecular dispersion in a single‐component organic molecular crystal. The results demonstrate that the BTQBT molecules have a strong intermolecular interaction, which can be derived from the introduction of a covalent interaction between sulfur atoms in addition to the usual intermolecular interaction by van der Waals forces.

The title electron acceptor, bis[ 1,2,5] thiadiazolotetracyanoquinodimethane (BTDA, 1), formed weak electrondonor-acceptor (EDA) complexes with arylolefins such as styrene (ST) and divinylbenzenes (DVs). Upon chargetransfer (CT) excitation of these complexes in MeCN, the [2 + 2]-type cycloadducts (2) were formed via a single electron transfer. Similar cycloaddition reactions were efficiently induced when the solid-state molecular complexes of 1 and arylolefins were irradiated. In contrast to the close similarities in solution photochemistry, the solid-state reactivities of three isomeric divinylbenzenes (oDV, mDV, pDV) were quite dissimilar because of the different molecular overlaps of 1 and DVs in the crystal. The apparent reactivity of the oDV- crystal was much higher than that in solution as in the case of the ST-1 crystal, and adduct 2o was formed via the single crystal-to-single crystal transformation. Because of the asymmetric crystal structure in oDV- , the optically pure product with 95% ee was obtained from the achiral components without any external chiral source. On the other hand, the incomplete conversion of the mDV-1 crystal to 2m is due to the crystal-to-amorphous transformation, and the 1:2 adduct 6 was formed on irradiation of the pDV-1 crystal which could not be obtained on excitation of the EDA complex in MeCN.

4-(1,3-Dithiol-2-ylidene)-4H-cyclopenta[2,1-b;3,4-b']dithiophenes 1 and 7-(1,3-dithiol-2-ylidene)-7H-cyclopenta[1,2-b;4,3-b']]dithiophenes 2 were prepared by Wittig-Horner or Wittig reactions. The X-ray structural analyses of the parent compounds 1a and 2a reveal that both molecules have planar structures with short intermolecular S...S contacts, and 2a additionally has short intramolecular S...S contacts. They have low oxidation potentials and absorptions in a long wavelength region due to the 1,3-dithiole skeleton. Electrochemical oxidation of 1 and 2 afforded the corresponding polymers 3 and 4, which have low oxidation potentials. Electrochemically dedoped films of 3 and 4 have interband absorptions at 610-690 nm and 420-590 nm, respectively, in their electronic spectra

4,7-Bis(2-thienylethynyl)-2,1,3-benzothiadiazole was prepared by Sonogashira coupling. The crystal structure showed that one thiophene ring is coplanar and the other is perpendicular to the benzothiadiazole ring.

In the crystal structures of the title compounds, C(6)H(2)I(2)N(2)S, (I), and C(12)H(4)I(2)N(4)S(2), (II), respectively, a large number of short inter-heteroatom contacts, such as S...N, I...I and N...I, are observed. In (II), which is non-centrosymmetric, two halves of the molecule are related by a crystallographic twofold axis.

In the title complex, (C16H36N)2[Ni(C6N2S4)2], the centrosymmetric dianion is flat. The Ni atom has square-planar coordination, with Ni—S bond lengths of 2.1836 (16) and 2.1940 (18) A.

BTQBT (bis-(1, 2, 5-thiadiazolo)-p-quinobis(1, 3-dithiole)) films have been prepared as active semiconducting layers of organic field effect transistors (FETs). BTQBT films showed a p-type semiconducting behavior. The hole mobility and on/off ratio of BTQBT films under ultrahigh vacuum conditions reached to 0.2 cm2/Vs and 108, respectively, by optimization of the growth conditions. These values are in the same order as those of pentacene thin films, which indicates that BTQBT molecules have a great potential for active layers of organic electronic devices.

Dioxopyrrolopyrrole derivatives (III) and (V) are applied to organic field-effect transistors as n-channel semiconductors.

In the title complex, (C(16)H(36)N)(2)[Pd(C(6)N(4)S(2))(2)], the centrosymmetric dianion is planar, with an r.m.s. deviation of 0.034 (8) Å. The Pd(II) atom, lying on an inversion center, has a square-planar coordination geometry, with Pd-S bond lengths of 2.276 (3) and 2.294 (3) Å.

A series of novel diphenylpyran derivatives (VII) is synthesized as photosensitizers of dye-sensitized solar cells.

The title 1,3-dithiole compounds which were synthesized using a Wittig-Hornor reaction have a planar structure with both inter- and intramolecular short S···S contacts. Their electrochemical oxidation gave polythiophene derivatives which have lower oxidation potentials than polythiophene and the conductivity of the nonsubstituted derivative was 3.5 × 10−3 S cm−1.

We present here a new narrow band gap periodic copolymer (1) consisting of aromatic thiophene and nonclassical thiophene repeat units. The monomer molecule (6) was synthesized from 3,4-diaminothiophene, and the electrochemical oxidation afforded the polymer (1). The optical and electrochemical properties of the monomer molecule and its polymer are discussed.

We experienced a case of perforated ulcer of the small intestine due to secondary amyloidosis in a 77-year-old woman having an underlying disease of rheumatoid arthritis. The patient was seen at the hospital because of abdominal pain. Based on clinical and imaging findings a diagnosis of general peritonitis due to intestinal perforation was made. Laparotomy was carried out and extended ulcer and perforation of the small intestine were found. Excision of the small intestine and enterostomy were performed. Histopathological examination of the excised specimen revealed deposites of amyloid ranging from the mucosa to submucous vascular wall. This amyloid was determined as AA protein by immunohitological staining. Amyloydosis in this patient might be secondary to RA. It has been reported that RA is the most common underlying disease for secondary amyloidosis. If a patient with RA has gastrointestinal symptoms such as nausea, vomiting, abdominal distension, abdominal pain and diarrhea, possible association of intestinal amyloidosis should be entertained.

TTF vinylogues containing hydroxyphenyl groups were newly prepared. They are stronger electron donors than BEDT-TTF and afforded their cation radical salts as single crystals upon electrochemical oxidation. X-Ray structure analysis has revealed their unusual crystal structures, where π-overlapping and hydrogen bonding play a crucial role in constructing them.

The structure of the title compound, C20H14N22+·C6Cl2O42−, contains one-dimensional hydrogen-bonded molecular tapes along the [113] direction. The molecular tapes are connected via two N—H⋯O hydrogen bonds in R12(5) patterns.

Terthiophene and bithiophene derivatives functionalized by BF(2) chelation were synthesized as a new type of electron acceptor, and their properties were compared to those of bifuran and biphenyl derivatives. These new compounds are characterized by quadrupolar structures due to resonance contributors generated by BF(2) chelation. The bithiophene derivative has a strong quadrupolar character compared with the bifuran and biphenyl derivatives because their hydrolytic analyses indicated that the bithiophene moiety has a larger on-site Coulomb repulsion than the others. The terthiophene derivative has a smaller on-site Coulomb repulsion than the bithiophene derivative due to the addition of a thiophene spacer. These BF(2) complexes exhibit long-wavelength absorptions and according to measurements of ionization potentials and absorption edges they have energetically low-lying HOMOs and LUMOs. The crystal structure of the bithiophene derivative is of the herringbone type, with short F···S and F···C contacts affording dense crystal packing. n-Type semiconducting behaviour was observed in organic field-effect transistors based on these BF(2) complexes.

Tetrathiafulvalenes such as bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) having alkylthio substituents have been prepared in good yields by direct desulphurization of 1,3-dithiole-2-thiones with trimethyl phosphite under high pressure.

The synthesis and properties of the title electron donors which are tetrathiafulvalene (TTF) or bis(ethylenedithio)TTF (BEDT–TTF) analogues with a quinoid structure are described; the crystal structure of a derivative is also presented.

The synthesis and properties of the novel electron donors which are tetrathiafulvalene (TTF) analogues with a quinoid structure containing fused-selenadiazole rings are described.

1-Aza- and 1,3-diazaazulenium ions, stable heterocyclic cations, were easily prepared. They afforded conducting salts of tetracyanoquinodimethane radical anions (TCNQ .− ) by metathesis with Li + TCNQ .− . Some salts exhibit good conductivities despite 1:1 salts. The nitrile stretching frequencies of the salts obtained here are not linearly correlated with the degrees of charge transfer due to strong interactions between the nitrile groups and heteroatoms of the cations. X-ray structural analysis of 2-imino-3-thia-1-azaazulenium-TCNQ salt reveals the novel crystal structure in which a ribbon-like network is formed by short interheteroatom contacts and hydrogen bondings.

Single crystals of bis(1,2,5-thiadiazolo)-p-quinobis(1,3-dithiole)(BTQBT) were grown either by recrystallization from a nitrobenzene solution or by sublimation in nitrogen atmosphere The electrical resistivities were 1.2 × 103Ω cm and 2.7 × 105Ω cm at room temperature for a crystal grown by recrystallization and that obtained by sublimation, respectively. These values are remarkably low for a single-component organic crystal. In addition, the BTQBT crystals have a small anisotropy in resistivity (ρ⊥/ρ∥, ≈ 2), which is ascribed to strong intermolecular interactions inherent in the crystal structure. They show a Hall effect which is an unusual observation in organic semiconductors. The sign of carriers was determined to be positive and the Hall mobility was found to be ca. 4 cm2 s–1 V–1 at room temperature.

The intermolecular contacts between chalcogen atoms and cyano lone pairs were found to stabilize the crystalline state by electrostatic interaction. This interaction is one of the sources of the directionality in crystal paccking of organic molecules and causes the formation of various types of inclusion lattices in the charge-transfer (CT) crystals of I-3. By using highly selective formation of CT crystals with substituted aromatic hydrocarbons, particular isomers such as p-xylene or 2,6-dimethylnaphthalene (2,6-DMN) could be separated from the corresponding isomer mixtures