Crystal structures of the organic metals (ET)2[Hg(SCN)Cl2] and (ET)2[Hg(SCN)2Br]

The compositions and structures of two new organic metals based on ET [where ET = bis(ethylenedithio)tetrathiafulvalene], viz., (ET)₂[Hg(SCN)Cl₂], with a metal-dielectric transition temperature (T_m-d) of 35°K, and (ET)₂[Hg(SCN)₂Br], with T_m-d = 140°K, were established by x-ray diffraction analysis. The crystal structures of the investigated compounds are similar to the structure of the previously studied organic metal (ET)₂[Hg(SCN)₂Cl] with T_m-d = 50°K. The principal crystallographic data for (ET)₂[Hg(SCN)Cl₂] are as follows: a = 36.64(1), b = 8.300(4), c = 11.798(1) Å, = 89.91(3)°, V = 3588.1(9) ų, space group Cc, Z = 4, d_calc = 2.05 g/cm³. The principal crystallographic data for (ET)₂[Hg(SCN)₂Br] are as follows: a = 37.088(14), b = 8.338(3), c = 11.738(5) Å, = 89.71(3)°, V = 3629.6(8) ų, space group C2/c, Z = 8, d_calc = 2.15 g/cm³. A characteristic feature of the crystal structure of the investigated compounds is alternation of the anion and cation layers along the a axis of the crystal. In the cation layer of the k type the ET are interconnected by shortened S...S intermolecular contacts (3.39–3.58 Å). The [Hg(SCN)_3–nX_n]^– anions (X = Cl, Br; n = 1, 2) form polymeric chains with one or two bridged SCN groups. A tendency for a decrease in the metal-dielectric transition temperature with a decrease in the volume of the anion is detected in the (ET)₂[Hg(SCN)_3–nX_n] salts, where X = Cl and Br, and n = 1 and 2.Institute of Chemical Physics, Russian Academy of Sciences, 142432 Chernogolovka. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 10, pp. 2323–2331, October, 1992.     

OXAZOLIDONES ET DIOXOLONNES DU GERMANIUM (IV) ET (II) DU PHOSPHORE (III), DE L'ARSENIC (III) ET DU SOUFRE

Abstract

Diffèrents modes de synthèse d'oxazolidones 1.2.4-7 et de dioxolonnes 8-11 germaniées sont décrites.

La stabilité thermique de germadioxolonnes a été étudiée. La décomposition procède d'un méchanisme du type (2 + 2 + 1), avec ouverture du cycle et formation de germylène.

La réactivité chimique des oxazolidones et dioxolonnes germaniées a été étudité. Des réactions d'échange avec des dérives organominéraux dichlorés conduit facilement et avec de bons rendements aux derives isologues, phosphorés(III). arseniés(III), soufrés. ou germaniés(IV). La réaction d'échange entre une dioxolonne germaniée et le dichlorogermylène nous a permis d'obtenir un nouveau germylène fonctionnel cyclique stable 20 qui a été caractérisé par spectrographie (RMN ¹H. masse).

Different synthetic ways for germaoxazolidones 1.2.4-7 or dioxolonnes 8-11 have been described.

The thermal stability of germadioxolonnes has been studied. Decomposition occurs by a [2 + 2 + 1] ring opening with formation of germylene.

The chemical reactivity of germaoxazolidones or dioxolonnes has been studied. Exchange reactions with dihalogenated covalent compounds occur readily lcading to phosphorus(III). arsenic(III). sulphur or germanium(IV) analogs.

From dichlorogermylene, new stable fonctionnal cyclic germylene 20 is obtained and characterized.     

SPIROPHOSPHORANYLATION D'HYDROXYACIDES NATURELS (ACIDES MALIQUE,CITRIQUE ET TARTRIQUE)—EMETIQUES PHOSPHORES ET OLIGOMERES A PHOSPHORE PENTA ET HEXACOORDINE

Abstract

Condensing tartaric acid (R, R) and PCl₃, we obtained oligomers 3 and cyclic dimer 4. Oxidizing these compounds by DMSO, we prepared hydroxyphosphoranes 6–9, while reaction of orthoquinones gave six-coordinated compound 10. Compound 4 reacts with triethylamine leading to an equilibrium between phosphoranide 5 and phosphite 5'. The more likely structure of oligomers is a sequence of TBP arranged on a helix, whereas dimers should have an emetic structure with pentacoordinated phosphorus atoms. These results are supported by nmr analysis, molecular weight and elemental analysis. All these compounds have strong optical activity. On the other hand, condensing PCl₃ and malic or citric acids, we synthetized new functionalized spirophosphorans 2.

En condensant l'acide tartrique (R, R) et PCl₃, nous avons obtenu des oligomères 3 et le dimére cyclique 4. En oxydant ces composés par le DMSO, nous avons préparé les hydroxyphosphoranes 6–9, tandis que la réaction des orthoquinones a donné le composé a phosphore hexacoordiné 10. Le composé 4 réagit sur la triéthylamine, conduisant à un équilibre entre le phosphoranure 5 et le phosphite 5'. La structure la plus probable des oligomères est une série de BPT placées sur une hélice, tandis que les dimères devraient avoir une structure émétique avec les atomes de phosphore pentacoordinés. Ces résultats s'appuient sur l'analyse des spectres de RMN, les masses moléculaires et l'analyse élémentaire. Tous ces composés présentent une forte activité optique. Par ailleurs, en condensant PCl₃ et les acides malique ou citrique, nous avons synthétisé des spirophosphoranes fonctionnalisés nouveaux 2.     

Crystal structure of the organic metal (ET)2[Hg(SCN)2Cl] withT M-D=50 K

The composition and structure of the radical-ion salt (ET) ₂ [Hg(SCN) ₂ Cl], a new organic metal withT _M-D=50 K, were established in an x-ray structure investigation. Principal crystallographic data:a=36.69(1),b=8.302(8),c=11.732(8) Å, =90.02(6)°, space groupCc, Z=4,d _calc=2.08 g/cm ³ ,R=0.067. The crystal structure of the salt consists of an alternation of organic (cationic) and inorganic (anionic) layers along the axisa. The anionic layer consists of the polymeric chains in which the [Hg(SCN) ₂ Cl]^– ions are linked together along the axisc through secondary Hg···N bonds with lengths of 2.75(3) and 2.98(8) Å. On account of these interactions the trigonal configuration of the bonds of the Hg atom is built up to trigonal-bipyramidal. In the organic layer with a structure of the type the ET cations form dimers with an interplanar distance of 3.53 Å. ET cations belonging to neighboring dimers are linked together through shortened intermolecular S...S contacts with lengths of 3.40–3.50(2) Å.Institute of Chemical Physics, Russian Academy of Sciences, Chernogolovka 142432. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 4, pp. 903–909, April, 1992.     

Synthesis, Structure and Conductivity of the New Charge-transfer Salt (ET)_2(CH_2=CH-CH_2-SO_3)·H_2O

ET is one of the most famous electron-donor molecules, which forms charge-transfer complexes (abbr. CT-complexes) with various types of counterions. These complexes have received intense attention because a wide range of physical properties such as conductivity and superconductivity1, ferromagnetism2-4 and nonlinear optical properties5 was found in these materials. Although the majority of the ET-based CT-complexes were prepared by combining with inorganic counterions, CT-complexes with o…     

New organic two-dimensional metals, (ET)4(Hg2X6)·PhCl (X=Cl,Br)

Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2872–2873, December, 1990.     

A chiral molecular conductor: synthesis, structure, and physical properties of [ET]3[Sb2(L-tart)2].CH3CN (ET = bis(ethylendithio)tetrathiafulvalene; L-tart = (2R,3R)-(+)-tartrate)

The salt [ET](3)[Sb(2)(L-tart)(2)].CH(3)CN (1) has been obtained by electrocrystallization of the organic donor bis(ethylendithio)tetrathiafulvalene (ET or BEDT-TTF) in the presence of the chiral anionic complex [Sb(2)(L-tart)(2)](2-) (L-tart = (2R,3R)-(+)-tartrate). This salt crystallizes in the chiral space group P2(1)2(1)2(1) (a = 11.145(2) angstroms, b = 12.848(2) angstroms, c = 40.159(14) angstroms, V = 5750.4(14) angstroms(3), Z = 4) and is formed by alternating layers of the anions and of the organic radicals in a noncentrosymmetric alpha-type packing. This compound shows a room temperature electrical conductivity of approximately 1 S.cm(-1) and semiconducting behavior with an activation energy of approximately 85 meV. Analysis of the magnetic susceptibility and band structure, however, suggests that this compound should be a narrow band gap semiconductor.     

Synthesis, crystal structure and properties of the semiconducting salts (TTF)2[Ni(dtcr)2] and (ET)2[Ni(dtcr)2] based on [Ni(dtcr)2] dianions (dtcr = dithiocroconate)

The first examples of CT salts based on [Ni(dtcr)2] dianions (1) (dtcr = dithiocroconate = 4,5-disulfanylcyclopent-4-ene-1,2,3-trionate), (TTF)2[Ni(dtcr)2] (TTF = tetrathiafulvalene) (2) and (ET)2[Ni(dtcr)2] [ET = bis(ethylenedithio)tetrathiafulvalene] (3) are reported. The redox-active dianion 1, containing oxo-groups in the periphery of the molecule, has been selected to investigate the role of the oxo-groups in promoting intermolecular interactions and hopefully their conducting properties. The salts 2 and 3 have been prepared by electrocrystallisation methods and 3 shows a semi-metallic behaviour: sigma = 1 x 10(-3) omega(-1) cm(-1) at room temperature, with a low activation energy 60 meV, while crystals of 2 were unsuitable for conductivity measurements. The X-ray structural characterisation shows an alternate dianion-(cation)2 stacking and the capability of the oxo-groups to promote interstack contacts. In 2, the TTF donors are present as face-to-face dimers of monocations (D2)2+. The stacking arrangement is different in 3, where ET monocations stack along two directions ([110] and [110]) in the same manner, with the repeating sequence (ET)-(ET)-[Ni(dtcr)2]-(ET)-(ET) and are almost parallel to each other, with interplanar distances of 3.575 angstroms. Both structures are built on a dianion and two donor molecules, each one with a charge of +1. Diffuse reflectance combined with vibrational spectra complement structural results well. Crystal data: both 2 and 3 crystallise in the monoclinic space group P2(1)/c with a = 8.6340(8) angstroms, b = 21.586(2) angstroms, c = 7.5960(8) angstroms, beta = 95.625(11) degrees and V = 1408.9(2) angstroms3 for 2 and with a = 9.3700(7), b = 7.4410(6), c = 28.278(2) angstroms, beta = 99.039(6) degrees, V = 1947.1(3) angstroms3 for 3.     

The Inorganic-free Organic Conductor α''''-(ET)_2C_6H_4(SO_3)_2 : Its Synthesis, Structure, and Conductivity

Having more than twenty years?glory, ET series still keep the most promising family in various kinds of organic conductors. Most of ET based molecular conductors consist of organic cationic ET+0.5 radical and certain anionic inorganic component such as the superconductor k-(ET)2Cu[N(CN)2]Cl (TC = 12.8K, 0.3kbar)1. Recently, the first purely organic superconductor b-(ET)2SF5CH2CF2SO3 (TC = 5.2K)2 has been reported, which aroused our interest on this kind of inorganic-free organic c…     

SYNTHESE ET PROPRIETES DE 2-HYDRAZONOPHENYL-SELENOACETAMIDES

Abstract

The two steps synthesis of 2-hydrazonophenylselenoacetamides is described starting from sulfur analogs. Depending on the substitution of hydrazono and selenamide groups they allow the preparation of a 1,2,3-selenadiazolium salt, a 5-imino-Δ³-1,2,3-selenadiazoline, 3,6-dihydro-2H-1,3,4-selenadiazines and a 5-selenoxo-2,3,4,5-tetrahydro-1,2,4-triazin- 3-one.

Les 2-hydrazonophénylsélénoacétamides sont obtenus en deux étapes à partir de leurs analogues soufrés. Selon le degré de substitution de l'atome d'azote du groupement hydrazono et de celui du sélénamide, ils permettent d'accéder à un sel de 1,2,3-sékénadiazolium, à une 5-imino-Δ³-1,2,3-sélénadiazoline, aux 3,6-dihydro-2H- 1,3,4-sélénadiazines ou à une 5-sélénoxo-2,3,4,5-térahydro-1,2,4-triazin-3-one.     

Radiation grafting of 4-vinylpyridine onto poly-tetrafluoroethylene-perfluorovinylether (TFA) and poly-tetrafluoroethylene-polyethylene (ET) films

Preparation of membranes of poly-(tetrafluoroethylene-perfluorovinylether (TFA) and poly-tetrafluoroethylene-polyethylene (ET) films grafted with 4-vinylpyridine using γ-rays has been carried out. The appropriate reaction conditions were selected. Furthermore, quaternization of the pyridine of the grafted chains was conducted. The effect of monomer concentration on the rate of grafting was also investigated. The order of the grafting rate gram per hour depending on monomer concentration was found to be 0.94 and 1.0 for TFA and ET films, respectively. Some selected properties of the grafted films such as swelling behavior, dimensional stability, mechanical and electrical properties were investigated. The grafted film of TFA and ET showed a marked decrease in elongation with a significant increase in the tensile strength.     

Inhibition of endothelin (ET)-1-and ET-2-induced vasoconstriction by anti-ET-1 monoclonal antibody

We produced a monoclonal antibody to endothelin (ET)-1, tested cross-reactivities with the related peptides by enzyme immunoassay, and investigated the effects of the antibody on ET-1- or ET-2-induced vasoconstriction of rat isolated thoracic aorta. The antibody recognized ET-1, ET-2 and ET-3, and the immunoreactive site proved to be the N-terminal region but not the C-terminal region of ET-1. Moreover, at an approximate molar-equivalent concentration, the antibody absorbed ET-1 and ET-2, and significantly inhibited ET-1- and ET-2-induced vasoconstriction notwithstanding the presence of the endothelin receptor.     

Synthesis and crystal structure of an organic semiconductor (ET)4[Hg2I6]

A new cation-radical salt (ET)₄[Hg₂I₆] (1), where ET is bis(ethylenedithio)tetrathiafulvalene, has been synthesized in the system ET-HgI₃ ^–-PhCl. An X-ray study of 1 (a=41.02(5),b=23.01(1),c=8.233(2) Å,V=7772(3) ų, space groupPc2₁ b,Z=4,d _calc=2.308 g cm^–3) has established its composition, chemical formula, and the main structural features. The ET cation-radicals are packed in the conducting layer, the type of packing is ; the [Hg₂I₆]^2– anion has a dimeric structure. The temperature dependence of the conductivity of the (ET)₄[Hg₂I₆] crystals (₃₀₀=6 Ohm^–1 cm^–1) has a semiconducting character.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1240–1244, July, 1994.We thank M. G. Kaplunov for his participation in the discussion of the obtained results.This work was financially supported by the Scientific Council on the Problems of High-Temperature Superconductivity (Grant No. 90346 Metallorg) and the Russian Foundation for Basic Research (Project No. 93-02-2384).