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The asymmetric unit of the title salt, (C10H8S8)[Re2Br6(CH3COO)]·0.5C2H3Cl3, contains one bis(ethylenedithio)tetrathiafulvalene (ET) radical cation, one μ2-acetato-bis[tribromidorhenate(III)] anion and a 1,1,2-trichloroethane molecule with half-occupancy disordered about a twofold rotation axis. The tetrathiafulvalene fragment adopts an almost planar configuration typical of the ET radical cation. The C atoms of both ethylenedithio fragments in the cation are disordered over two orientations with occupancy factors 0.65:0.35 and 0.77:0.23. In the anion, six Br atoms and a μ2-acetate ligand form a strongly distorted cubic O2Br6 coordination polyhedron around the Re2 dinuclear centre. In the crystal, centrosymmetrically related ET cations and Re2O2Br6 anions are linked into dimers by π–π stacking interactions [centroid-to-centroid distance = 3.826 (8) Å] and by pairs of additional Re...Br contacts [3.131 (3) Å], respectively. The dimers are further packed into a three-dimensional network by non-directional interionic electrostatic forces and by C—H...Br and C—H...S hydrogen bonds. The disordered 1,1,2-trichloroethane molecules occupy solvent-accessible channels along the b axis.

An efficient construction of dihydroquinoline derivatives was realized through radical cation salt‐initiated C−H bond oxidation of unsaturated glycine esters. In the presence of dioxygen, the sp3 C−H bond adjacent to nitrogen was oxidized, followed by cascade cyclization, affording the desired dihydroquinoline products. The mechanistic investigation revealed that a radical intermediate was involved in this reaction. Radical ions: An efficient construction of dihydroquinoline derivatives was realized through radical cation salt‐initiated C−H bond oxidation of unsaturated glycine esters. In the presence of dioxygen, the sp3 C−H bond adjacent to nitrogen was oxidized, followed by cascade cyclization, affording the desired dihydroquinoline products. The mechanistic investigation revealed that a radical intermediate was involved in this reaction. [ABSTRACT FROM AUTHOR]

Abstract: A radical cation salt‐initiated phosphorylation of N‐benzylanilines was realized through an aerobic oxidation of the sp3 C−H bond, providing a series of α‐aminophosphonates in high yields. An investigation of the reaction scope revealed that this mild catalyst system is superior in good functional group tolerance and high reaction efficiency. The mechanistic study implied that the cleavage of the sp3 C−H bond was involved in the rate‐determining step. [ABSTRACT FROM AUTHOR]

A facile and efficient radical cation salt-induced approach to dihydroquinazoline derivatives has been developed by sp 3 C H oxidation, and the method uses readily available glycine esters as the starting material under aerobic oxidation conditions without addition of any additive. The present method provides a convenient and practical route for construction of quinazoline skeleton. [ABSTRACT FROM AUTHOR]

Three new radical cation salts of bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) with the magnetic metal complex anion [ReCl], viz., β-(BEDT-TTF)[ReCl] ( 1), α´-(BEDT TTF)[ReCl]•(DCE) ( 2), and δ-(BEDT-TTF)[ReCl]•(CB) ( 3) (DCE is dichloroethane, CB is chlorobenzene), were synthesized for the first time. The X-ray diffraction analyses of the obtained crystals at room and low temperatures showed that all of them had the sandwich structure characteristic of alternating anionic and cationic layers, which is characteristic of conducting radical cation salts. The structural phase transition accompanied by unit cell tripling and decreasing the symmetry from monoclinic to triclinic in the low-temperature phase occurs in the crystals of salt 2. The transition is related to modulated displacements of both [ReCl] anions and BEDT-TTF radical cations. A specific feature of the crystals of salt 3 is a strong positional disorder in the anionic layer, which is expressed as a random distribution of [ReCl] anions and CB solvent molecules in a ratio of 2 : 1 along the channels in the ordered cationic framework. [ABSTRACT FROM AUTHOR]

Designed by fragment-reassembly strategy, the reaction between glycine esters and cyclic enol ethers was achieved in the catalysis of TBPA +· /O 2 , yielding a series of quinoline-fused lactones and 2,3-disubstituted quinolines. This approach provided an efficient method to construct quinoline skeleton, in which two new rings and two new C–C bonds were built in one pot. [ABSTRACT FROM AUTHOR]

New radical cation salts based on 2,5-bis(1,3-dithiolan-2-ylidene)-1,3,4,6-tetrathiapentalene (BDH-TTP), viz., κ-(BDH-TTP)CuCl·(HO) ( 1) and κ-(BDH-TTP)[CuCl]· ·(HO) ( 2), were synthesized and structurally characterized. Single crystals were prepared by the electrochemical oxidation of BDH-TTP under galvanostatic conditions. The X-ray diffraction study showed that the salts have layered structures characterized by the presence of κ-type BDH-TTP conducting layers. These layers alternate with the complex anions composed of [CuCl] units and water molecules. Both salts exhibit the temperature dependence of the metallic conductivity down to 4.2 K. Spin-spin antiferromagnetic correlations in the Cu subsystem were observed in the crystals of 2. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis and the redox behaviour of electroactive donor molecules incorporating an azino spacer group between a benzoselenazole core and another heterocyclic moiety, either a benzoselenazole one or a thiazole one, are reported. Neutral complexes were obtained with TCNQ and, for the first time with dithiadiazafulvalene or diselenadiazafulvalene derivatives, cation radical salts by electrocrystallization. Crystal structures data of these complexes are presented and their geometries compared with those deduced from theoretical calculations. [Copyright &y& Elsevier]

Abstract: The first polymorph, κ″-(ET)2Cu[N(CN)2]Cl, of the well known Mott insulator κ-(ET)2Cu[N(CN)2]Cl has been prepared and its crystal and electronic structures have been examined. The polymorph has monoclinic symmetry in contrast with the orthorhombic one of the isostructural κ-salts of the family (ET)2Cu[N(CN)2]X (X=Cl, Br, I). The monoclinic phase exhibits a layered structure in which the conducting layers are packed in a κ-type arrangement and the anion sheets consist of polymeric zigzag chains formed by Cu[N(CN)2]Cl units. The main structural differences with the orthorhombic κ-salts are that the anion sheets are disordered and the ET molecules are less planar. The new polymorph shows metallic type resistivity down to 4.2K. [Copyright &y& Elsevier]

Abstract: The synthesis of the protected TTF tetrathiolate 2,3,6,7-tetrakis(2-cyanoethylthio)tetrathiafulvalene (TCE-TTF), as well as those of five new radical cation salts [TCE-TTF](X), X− =PF6 −, CF3SO3 −, BF4 −, obtained by electrocrystallization technique is presented. Five crystal structures of these materials based on their fully oxidized donor molecules are described. The flexibility of the cyanoethylene arm yields two conformations cis and trans to the molecule. Then compounds with PF6 − and BF4 − anions crystallized as two different phases. All these materials are insulators, and the magnetic studies of one phase of [TCE-TTF](PF6) revealed an antiferromagnetic behavior. [Copyright &y& Elsevier]

Abstract: The new radical cation salt based on bis(ethylenedithio)tetraselenafulvalene (BETS) with the square planar [Ni(CN)4]2− anion was synthesized by electrocrystallization: (BETS)4·Ni(CN)4. X-ray analysis, electron transport, magnetotransport and electronic band structure calculations are presented and discussed. [Copyright &y& Elsevier]

Seven conductive radical cation salts based on MDSe-TSF (methylenediselenotetraselenafulvalene) have been synthesized by electrocrystallization in the presence of Cl−, Br−, I3−, I2Br−, PF6−, ClO4−, and Cu(NCS)2− counter anions. The crystal appearances of these salts fairly depend on the anions employed. X-ray crystallographic analyses have revealed that the PF6 and ClO4 salts in the shape of brown thin plates adopt the θ-type structures characterized by the herringbone arrangement of donor stacks, whereas the Cl and Br salts in the shape of black thick plates favor the κ-type structures with the orthogonal arrangement of donor dimers. Regardless of different crystal appearances or crystal packing patterns, all these salts show high conductivity (>102 S cm−1) at room temperature and retain metallic properties down to 4.2 K. Of them, the Br salt shows a weak but distinct diamagnetic shielding signal below 4 K in the dc magnetization measurement under zero-field-cooled (ZFC) condition, suggesting a sign of superconductivity. The band calculations of both PF6 and Br salts demonstrate closed Fermi surfaces indicative of two-dimensional molecular conductors. [Copyright &y& Elsevier]

The first radical cation salts based on BETS and ET π-donors with dicyanamide-cuprate counterions were synthesized. Their crystal and electronic structures as well as transport and magnetic properties were studied. • First radical cation salts with paramagnetic dicyanamidocuprate (Cu2+ and Cu1+, Cu2+) anions. • Semiconductor – semiconductor phase transition with a large hysteresis. • Effect of pressure on metal-insulator and semiconductor-semiconductor transitions. • First order phase transition associated with charge distribution. Electrocrystallization of bis(ethylenedithio)tetraselenafulvalene (BETS) and bis(ethylenedithio)tetrathiafulvalene (ET) in the presence of an electrolyte (Ph 4 P)[Cu(dca)] 3 ⋅H 2 O [(dca) = N(CN) 2 ] has been studied using different solvents. A new organic metal (BETS) 2 Cu(dca) 3 (1), and the first radical cation salt with 3D dicyanamidocuprate anion, incorporating both diamagnetic Cu1+ and paramagnetic Cu2+atoms, (ET) 2 Cu 1.8 (dca) 4 (2) have been obtained. Crystal structure, conducting properties of both salts, as well as the electronic structure of 2 and its structural analog (ET) 2 CuMn(dca) 4 (3) were analysed. The salts 1 and 2 have layered structures. In contrast to the BETS radical cation salt 1 , complex 2 is characterized by the presence of a 3D polymeric anion built into the ET radical cation layers. At ambient pressure, the resistance of the crystals 1 shows semimetal behaviour down to 30 K. Below 30 K, the resistance sharply increases and the sample becomes insulating. The application of a pressure of about 3 kbar suppresses the metal-insulator transition. The salt 2 undergoes a semiconductor I - semiconductor II phase transition, which is manifested by a jump in the resistance and a hysteresis in the R(T) curves in a very large temperature range (185 – 250 K). The phase transition is accompanied by changes in the charge state of the ET molecules, and notable structure changes in the anion layer, especially in the environment of Cu2+. For the salt 3 the calculated selfconsistent charges show upon cooling a sharp increase of charge order between 291 K and 285 K. [ABSTRACT FROM AUTHOR]

Electrocrystallizaion of MDT-TSF (methylenedithiotetraselenafulvalene) in the presence of (n-Bu4N)AuI2, (n-Bu4N)PF6, or a mixture of Cu(SCN), KSCN, and 18-crown-6-ether as a supporting electrolyte gave (MDT-TSF)-X salts (X=AuI2, PF6, or Cu(NCS)2). X-ray structural analyses revealed that the salts adopt various types of crystal structures depending on the counter anion involved; the AuI2 salt takes a characteristic uniform stacking structure, the PF6 salt θ-type, and the Cu(NCS)2 salt κ-type structure. Regardless of the structure type, all the salts are highly conductive at room temperature (>102 S cm−1) and retain metallic down to low temperature. Of them, the AuI2 salt having a high conductivity of 2000 S cm−1 at room temperature showed a superconducting transition at 4.5 K. [Copyright &y& Elsevier]

A new radical cation salt based on the dithiolate complex Pd(dddt)2 (dddt=5,6-dihydro-1,4-dithiine-2,3-dithiolate) with the tetrahedral anion [GaBr4]− was synthesized. The crystal and molecular structure was determined by XRD analysis. The crystal structure of the salt contains Pd(dddt)2 cation layers alternating with layers of [GaBr4]− anions along the c axis of the unit cell. The cation layers contain stacks of Pd(dddt)2, with a Pd...Pd distance of 3.011 Å. The electroconductivity of [Pd(dddt)2]2GaBr4, single crystals at room temperature is 0.25 Ohm−1 cm−1 and decreases with temperature decrease, the activation energy being E a=0.66 eV. [ABSTRACT FROM AUTHOR]